Introduction: Our toughest battles are with ourselves
2 The "call is coming from inside the house" story was made into the 1979 movie, "When a Stranger Calls".
3 The official U.S. Government Human Genome Project website:

Excellent books on the modern Darwinian revolution include:

Dawkins, Richard. 1976. The Selfish Gene. Oxford University Press.

Pinker, Steven. 1997. How the Mind Works. Norton.

Wilson, Edward Osborne. 1978. On Human Nature. Harvard University Press.

Wright, Robert. 1994. The Moral Animal: Evolutionary Psychology and Everyday Life. Pantheon Books.

For the more academically minded:

Hamilton, William D. 1964. "The Genetical Evolution of Social Behavior I and II." Journal of Theoretical Biology 7: 1-16, 17-52.

Trivers, Robert. 1971. "The Evolution of Reciprocal Altruism." Quarterly Review of Biology 46(4): 35-57.

Barkow, Jerome H., Leda Cosmides and John Tooby, Eds. 1992. The Adapted Mind: Evolutionary Psychology and the Generation of Culture. Oxford University Press.

Daly, Martin and Margo Wilson. 1983. Sex, Evolution, and Behavior. Wadsworth Publishing Co.

Krebs and Davies. 1993. An Introduction to Behavioral Ecology, 3rd edition. Blackwell Scientific Publications.

Wilson, Edward Osborne. 1975. Sociobiology: The New Synthesis. Belknap Press of Harvard University Press.

3 The characteristics that are universally attractive include, but are not limited to, physical health, clear skin, and symmetry (right & left side of the body having the same proportions). One additional universal feature of sexual attraction is an aversion towards close genetic relatives. See the notes to the beauty chapter (pp 153-172) for detailed references on beauty universals.

Numerous studies have demonstrated that more symmetrical people are considered more attractive by others. See, for example: Perrett, D.I., D. Burt, D.M., I.S. Penton-Voak, K.J. Lee, D.A. Rowland, and R. Edwards. 1999. "Symmetry and human facial attractiveness." Evolution and Human Behavior 20:295-307. They found that, for males and females, when computer images were manipulated to increase the symmetry of the fac, the ratings of attractiveness also increased.

A related study, looking at men, also found that physical attractiveness was significantly correlated with symmetry. Interestingly, they also found that it wasn't even necessary to measure the symmetry of the man's face. In other words, men with asymmetrical fingers, feet, wrists, and elbows, have less attractive faces than men in whom these structures are more symmetrical. The data are in: Gangestad, S.W., R. Thornhill and R.A. Yeo. 1994. "Facial attractiveness, developmental stability, and fluctuating asymmetry." Ethology and Sociobiology 15:73-85.

And finally, Mealey et al. did an interesting study of twins, in which symmetry and attractiveness were measured in each. As would have been predicted by the studies cited above, the more symmetrical of the twins were rated as significantly more attractive than their less symmetrical co-twin. The study is in: Mealey L., R. Bridgstock, and G.C. Townsend. 1999. "Symmetry and perceived facial attractiveness: A monozygotic co-twin comparison." Journal of Personality and Social Psychology 76:151-158.

4 Evidence that we not only find symmetrical people more attractive but that we also prefer them as sexual partners is presented in: Thornhill, R. and S.W. Gangestad. 1994. "Human fluctuating asymmetry and sexual behavior." Physiological Science 5:297-302. This study of male college students found that more symmetrical men had had more lovers over the course of their lifetime and that they had lost their virginity at an earlier age.
4 It's clear where all of the studies above are pointing and, indeed, one study showed it to be true that women whose partners were more symmetrical reported more orgasms during sex than did women with less symmetrical partners. The study is: Thornhill, R., S.W. Gangestad, and R. Comer. 1995. "Human female orgasm and mate fluctuating asymmetry." Animal Behavior 50:1601-1615.

An important review that covered an impressively broad array of animal species (including both vertebrates and invertebrates), documented a consistent relationship between symmetry and nearly every important component of fitness, including: parasitism, fecundity, growth rate, survival, and metabolic efficiency. The study is Thornhill, R. and A.P. Moller. 1997. "Developmental stability, disease, and medicine." Biological Reviews of the Cambridge Philosophical Society 72:497-548.

For example: barn swallows showed increased asymmetry following infection with a parasitic mite, reindeer treated with an anti-parasite medication during antler development had more symmetrical antlers, and fruit flies infected with nematode parasites during development become less symmetrical as adults. These data are presented in: Moller, A.P. 1992. "Parasites differentially increase the degree of fluctuating asymmetry in secondary sexual characters.ƒ Journal of Evolutionary Biology 5:691-699, (barn swallows); Folstad, I., P. Arneberg, and A.J. Karter. 1996. "Antlers and parasites." Oecologia 105:556-558, (reindeer); and Polak, M. 1993. "Parasites increase fluctuating asymmetry of male Drosophila nigrospiracula: implications for sexual selection." Genetica 89:255-265, (fruit flies).

In the studies cited above, it's not clear whether the causal link between parasites and symmetry is one way or two. In and interesting study in house flies, individuals that were more asymmetric proved to be susceptible to infection when exposed to a fungus. The study is in: Moller, A.P. 1995. "Sexual selection, viability selection and developmental stability in the domestic fly, Musca domestica." Evolution 50:746-752.

5 Oprah really does have 7 Emmy awards. Moreover, her show has won 32 Emmys. A nice recounting of her triumphs can be found at:
7 For a recent summary of the research on fertility see Ellison, Peter T. 2001. On Fertile Ground. Harvard University Press.

An excellent study demonstrating the dramatic decrease in fertility that results from moderate weight loss is: Lager C. and P.T. Ellison. 1990. "Effect of moderate weight loss on ovarian function assessed by salivary progesterone measurements." American Journal of Human Biology 2:303-12. In this study, the same subjects were followed over multiple months and it turned out that women who were not dieting ovulated during every one of their cycles, while dieters, on the other hand, (who were losing weight at a rate of about four pounds per month) failed to ovulate in about 40% of their cycles.

7 An interesting and carefully-controlled study of the effects of moderate exercise on fertility showed that women running about 12 miles per week had significantly reduced progesterone levels that indicated in one-third of their cycles that no ovulation occurred. This study is: Ellison P.T. and C. Lager. 1986. "Moderate recreational running is associated with lowered salivary progesterone profiles in women." American Journal of Obstetrics and Gynecology 154:1000-1003.

Excellent monographs exist for a number of non-industrialized cultures. Included among those referenced throughout Mean Genes are:

The !Kung San of the Khalahari -- See Shostak, Margorie. 1981. Nisa, the life and words of a !Kung woman. Harvard University Press. and Lee, Richard. 1993, 2nd ed. The Dobe Ju/'hoansi. Harcourt Brace.
The Ache of South America -- See Hill, Kim and Magdelena Hurtado. 1996. Ache Life History: The Ecology and Demography of a Foraging People. Aline De Gruyter.
The Sambia of Papua New Guinea -- See Herdt, Gilbert. 1987. The Sambia. Ritual and Gender in New Guinea. Harcourt Brace Jovanovich.
The Yanomamo of South America -- Chagnon, Napoleon. 1992. Yanomamo, 4th edition. Harcourt Brace Jovanovich.

8 Darwin's classic is still a great read, Darwin, Charles. 1859. On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life. John Murray.

Prominent opponents to the use of genetic evolution and biology for understanding human behavior include Stephen J. Gould and Richard Lewontin. See their classic article: Gould, S. J. and R.C. Lewontin. 1979. "The Spandrels of San Marco and the Panglossian Program: A Critique of the Adaptationist Programme." Proceedings of the Royal Society of London 205: 581-588.

9 von Dornum, Miranda. 1997. DNA sequence data from mitochondrial COII and nuclear G6PD loci and a molecular phylogeny of the New World monkeys (Primates, Platyrrhini) / Ph.D. thesis. Harvard University. Available in Harvard archives -- HU 90.14582.11

Hirao, A., Y. Kong, S. Matsuoka, A. Wakeman, et al. 2000. "DNA Damage-Induced Activation of p53 by the Checkpoint Kinase Chk2." Science 287(5449): 1824-7.


Debt: Laughing all the way to the Darwinian bank
A study of people's saving desires and behavior is, Bernheim, Douglass. April 1995. "Do Households Appreciate Their Financial Vulnerabilities?" An Analysis of Actions, Perceptions, and Public Policy, in Tax Policy and Economic Growth, American Council for Capital Formation, Center for Policy Research.

U.S. Savings rate (data from Department of Commerce, Graph from Wall Street Journal)



U.S. personal Bankruptcy filings (from Wall Street Journal)


Nut caching in European red squirrels, Wauters, L.A. and P. Casale. 1996. "Long-term scatterhoarding by Eurasian red squirrels (Sciurus vulgaris)." J. Zool., Lond., 238: 195-207.

Red Squirrel

From the above paper, page 201: "In the deciduous woodland (of Belgium), 2200 cached food items were recovered of the 2800 estimated hoards (79%). Squirrels consumed 99% of cached cones, 62% of cached acorns and 92% of cached beechnuts."



A comprehensive review of animals that save via means other than body fat is, Vander Wall, S. B. 1990. Food Hoarding in Animals. University of Chicago Press.

See page 240, for instance: "Red squirrels (Tamiasciurus hudonicus), common inhabitants of coniferous forests throughout much of North America, and the closely related Douglas squirrel (T. douglasii) of the Pacific Northwest are among the most thoroughly studied of food-hoarding mammals . . . Red squirrels begin collecting and storing cones in late July or early August and continue for 4-8 weeks … Clarke (1939) estimated that red squirrels can collect and store about 1,000 red pine (Pinus resinosa) cones in a day, but they clip and store the large cones of limber pine (P. flexilis) at rates of only about twenty-nine to thirty-two cones per day (Benkman, Balda, and Smith 1984). … Middens usually contain 2-4 bushels (70-141) of cones, but instances of 8-15 bushels (282-528 l) being taken by cone collectors have been reported (Cox 1911; Korstian and Baker 1925; Yeager 1937; Baldwin 1942). M.C. Smith (1968) estimated that red squirrels stored between 12,000 and 16,000 white spruce (Picea glauca) cones in a 6-week harvest period in interior Alaska. Gurnell (1984) found a mean of 2,187 lodgepole pine cones in nine middens (range = 280-4,360 cones per midden). . ."

"Besides cones, red squirrels store various nuts, seeds, fruits, and some meat. Nuts stored include walnuts, hickory nuts (Layne 1954), chestnuts (Audobon and Bachman 1846, cited by Hatt 1929), beechnuts (Klugh 1927), and hazelnuts (Mailliard 1931). … Burton (1930) attributed to red squirrels accumulations of boxelder (Acer negundo) samaras found at the bases of trees, in hollow trunks, and in the crotches of tree branches. One of these caches contained more than a bushel (35 l) of seeds."


The original story of the grasshopper and ant was written by Aesop. It reads,

In a field one summer's day a Grasshopper was hopping about, chirping and singing to its heart's content. An Ant passed by, bearing along with great toil an ear of corn he was taking to the nest.

"Why not come and chat with me," said the Grasshopper, "instead of toiling and moiling in that way?"

"I am helping to lay up food for the winter," said the Ant, "and recommend you to do the same."

"Why bother about winter?" said the Grasshopper; we have got plenty of food at present." But the Ant went on its way and continued its toil. When the winter came the Grasshopper had no food and found itself dying of hunger, while it saw the ants distributing every day corn and grain from the stores they had collected in the summer. Then the Grasshopper knew:

It is best to prepare for the days of necessity.


!Kung San life in the 1960's is described in, Lee, Richard. 1993, 2nd ed. The Dobe Ju/'hoansi. Harcourt Brace.


Elephant Seals eating, saving, and mating behavior from, LeBoeuf, B.J. and R.M Laws. 1994. Elephant Seals. University of California Press.

Page 162, table 9.4 "Standard length, measured growth rate, and relative growth rate."

Males are considered fully-adult when they're about 9 years old.

Age Length (in cm) Length expressed in feet
182.9 ± 3.3 6.00
207.4 ± 2.4 6.80
232.7 ± 3.3 7.63
272.6 ± 5.7 8.94
304.7 ± 4.5 10.00
334.2 ± 2.9 10.96
356.7 ± 3.0 11.70
370.5 ± 3.9 12.15
390.6 ± 4.1 12.81
394.8 ± 5.7 12.94
395.4 ± 10.7 12.96
397.2 ± 3.6 13.02
395.7 ± 3.0 12.97

"Females fast while lactating [and lose up to 700 lbs], and the largest breeding males fast for more than one hundred days during the breeding season." -- p. xi

for males:

arrival [at beach] mean body mass: 1,430 - 2,265 kg

departure [at end of breeding season]: 895 - 1,500 kg

"Taking an extreme case, if a 3000-kg male loses 1000 kg while ashore. . ." -- p. 370, LeBoeuf and Laws, 1994.

N Body Mass (kg) kg loss per day % body mass loss per day kg loss per season % body mass loss per season duration of stay (days)
Males 13 1704 ± 213 7.1 ± 1.5 0.41 ± 0.06 622 ± 172 36.2 ± 6.6 91 ± 15
Females 22 489 ± 64 7.2 ± 1.0 1.48 ± 0.11 180 ± 30 36.8 ± 2.8 25 ± 2



LeBoeuf and Laws (cited above), Elephant Seals, Univ Cal Press, Berkeley LA London. 1994:

p. xi ". . . the largest breeding males fast for more than one hundred days during the breeding season."

18 gives the weight of a new Eldorado as between 3825lbs and 3856lbs. No length is given, although some of the other models can be around 16 feet long at maturity.

Bobby Sands's diary:

10/27/80: 1st hunger strike by the IRA "blanketmen," lasted for 53 days. There were no deaths. (Bobby Sands did not participate).

3/1/81: 2nd IRA hunger strike: "Having consumed only water and salt for his last 66 days, Bobby Sands died at the door of the British government on 5 May 1981."

20 The Border, 1982. Directed by Tony Richardson. Written by David Freeman, Walon Green, and Deric Washburn.

Discussion of the role of social security in alleviating poverty among the elderly,

"Following the outbreak of the Great Depression, poverty among the elderly grew dramatically. The best estimates are that in 1934 over half of the elderly in America lacked sufficient income to be self-supporting. Despite this, state welfare pensions for the elderly were practically non-existent before 1930. A spurt of pension legislation was passed in the years immediately prior to passage of the Social Security Act, so that 30 states had some form of old-age pension program by 1935. However, these programs were generally inadequate and ineffective. Only about 3% of the elderly were actually receiving benefits under these states plans, and the average benefit amount was about 65 cents a day."


Retirees in the U.S. have very little in the way of liquid financial assets, Poterba, James M. 1996. Personal Saving Behavior and Retirement Income Modeling: A research Assessment. in Eric A. Hanushek and Nancy L. Maritato, eds., Assessing Knowledge of Retirement Behavior: Commission on Behavioral and Social Sciences and Education (CBSSE).

        Median Financial assets for U.S Household head age 55-64


          $8,300 Total financial assets

        $36,000 Home equity

          $8,200 Other property

Those famous Calvin Klein ads.

24 Stanley, Thomas J. and William D. Danko. 1996. The Millionaire Next Door. Pocket Books.

Our instinctual fears are discussed in, Kellert, Stephen and E. O. Wilson, Eds. 1995. The Biophilia Hypothesis. Island Press.

"The human inclination to fear and avoid threatening aspects of nature has been particularly associated with reptiles such as snakes and arthropods such as spiders and various biting and stinging invertebrates... This potential has been described by Ulrich et al. in a review of the scientific literature (1991:206): 'Conditioning studies have shown that nature settings containing snakes or spiders can elicit pronounced autonomic responses... even when presented subliminally.' Schneirla (1965) further notes that the occurrence of 'ugly, slimy, erratic' moving animals, such as certain snakes and invertebrates, provokes withdrawal responses among vertebrate neonates in the absence of overt or obvious threat." --p. 57

"Ohman and Dimberg, using classical conditioning paradigms, were able to elicit and maintain fear responses to spiders, snakes, and hostile human faces but not to "neutral" stimuli such as flowers or to such modern hazards as guns." -- p. 167


Lapland and the use of cheese in, Einzig, Paul. 1966. Primitive money in its ethnological, historical, and economic aspects. 2nd ed. Pergamon Press. "In Lapland, cheese served as a currency up to the 19th century." -- p. 310

26 The origins of money, Quiggin, Alison. 1907. A Survey of Primitive Money; The Beginning of Currency. Methuen.

More on precursors to coin and paper money in, Einzig, Paul. 1966. Primitive money in its ethnological, historical, and economic aspects. 2nd ed. Pergamon Press.

In Norway, "butter was used for valuation in many commercial documents, the unit being a basket. Rents were often payable wholly or partly in butter. In 1309, ten baskets of butter bought a horse worth three cows." -- p. 275


Japan's problems with oversaving were described in The Wall Street Journal on May 17, 2000

Japan is the first major developed country since World War II to confront the 'paradox of thrift,' the condition John Maynard Keynes worried about, where bad times lead individuals to save more, suppressing overall demand and making a country even worse off.

So the Japanese government nudges its citizens to live it up. The Finance Ministry, concerned that families would simply tuck away a recent $500-a-household income-tax cut, launched a media blitz to advise people on how to spend the money.

A cartoon in a magazine ad shows a father excitedly reading about the cuts in the newspaper, inspiring his two young kids to dream of cake and candy and his blushing wife to ask for a blouse. A poster plastered in subway stations pictures an aerial shot of a crammed neighborhood with words emanating from the homes. "I'll drink a toast with fine wine," says one. "I'll finally buy those golf clubs," says another. One implores: "Let's spend it all at once!"

30 The Simpson's episode where Homer buys weight loss-products (but is inadvertently shipped vocabulary tapes): episode is 8f22, available online: Homers Buys it now!
31 People plan to be "good" (e.g. with video selections), but given the chance are "bad". Read, D., G. Loewenstein and S. Kalyanaraman. 1999. "Mixing virtue and vice: The combined effects of hyperbolic discounting and diversification." Journal of Behavioral Decision Making 12: 257-73.

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Fat: Please don't feed the humans

For more information and studies about Chantek, check out: (Note, this site is not always available). There is also an interesting article about Chantek and his trainer, Dr. Lyn Miles at:


An excellent source of information about orangutans can be found at:

36 A spectacular article on Organutans in the wild is, Knott, Cheryl. 1998. "Orangutans in the Wild." National Geographic, August 194(2): 30-57. Photographs in this piece are taken by Tim Laman.

An important article laying out the role of ancestral environments in the shaping of our genetic human nature is, Tooby, John and Leda Cosmides. 1990. "The Past Explains the Present: Emotional Adaptations and the Structure of Ancestral Environments." Ethology & Sociobiology, 11: 375-424.

36 The Harvard Chimpanzee site (location of the bulimia conversation) is the Kibale National Park in Western Uganda.
36 In many cultures where food is scarce, fatness is a positive signal of health and wealth. See, for example: Rosenblatt, P.C. 1974. "Cross-cultural perspective on attractiveness." In T. Huston (Ed.): Foundations of Interpersonal Attraction (pages 79-95). Academic Press. See also: Sheinin, R. 1990. Body Shame: Body Image in a Cultural Context. National Eating Disorders Information Centre Bulletin, 5.5:1-3.
36 "The fattening room is like paradise. Obesity is seen as something very special and sought after in this culture and an Iriabo works hard to achieve it." This is from the detailed description of the fat rooms of Nigeria in: Brink, P.J. (1989). The fattening room among the Annang of Nigeria. Medical Anthropology 12:131-143. Following the ritual, coming-of-age ceremony that takes place several years after reaching puberty, the young women--called Iriabos during the ceremony--enter the fattening room. Although some of the girls marry immediately after completing the ceremony, this is not always the case.
37 The importance to reproduction of having reserves of energy is discussed in: Hrdy, S.B. 1999. Mother Nature. Pantheon. See for instance, page 125: "with sufficient fat on board, some fat cells start to secrete the hormone leptin, which triggers endocrinological transformations leading to menarche. Some time after that, a young woman becomes fertile. By then she will have laid down sufficient fat to help carry her through pregnancy and lactation... this is termed 'reproductive fat'."
37 For an excellent and comprehensive account of the extent of starvation and malnutrition in the world, see the Food and Agriculture Organization of the United Nations page at:
38 For an overview of energy expenditure in daily life among modern day hunter-gatherers, see Cashdan, Elizabeth. 1989. "Hunters and Gatherers: Economic Behavior in Bands." in S. Plattner, ed., Economic Anthropology. Stanford, CA: Stanford University Press.

Obesity is a clinical term that is revised from time to time. According to the Centers for Disease Control, an individual is "overweight" if they have a Body Mass Index (BMI) greater than or equal to 25. This means that 54.6 % of Americans are overweight. A BMI greater than or equal to 30 is considered obese. This means that 22.6 % of the population are obese.

An excellent resource for more information is the American Heart Association. See, for instance:

39 A typical American gains about 20 pounds between the ages of 25 and 55. An outstanding summary of what scientists know about fat and obesity, including the relationship between weight gain and age, can be found in the Scientific American article: Gibbs, W.W. 1996. "Gaining on fat." Scientific American August 1996. This article also gives a nice summary of data bearing on the set-point theory.
39 A discussion of all the aspects of our health that would be improved if we lost 5 to 10 percent of our body weight can be found at:
A list of obesity related illnesses can be found at:
40 Biosphere 2 Center is a non-profit affiliate of Columbia University. For a detailed description and photos, see:
40 Because they couldn't grow as much food as they projected they would be able to, the Biodomers were forced onto a calorie-restricted dietary regime of about 1,800 calories per person per day.
40 Botanist Linda Leigh said personality differences and crop failures made life difficult for the Biodomers: "Food distribution became a very tense issue. . . I think that made us all a little cranky, always being hungry. . . If we ever all start talking to each other, that would be a major accomplishment." Associated Press. 1996. "Life inside Biosphere 2: food fights and bugs." July 29th 1996.
41 The starvation study where food became the favorite topic of discussion is reported in, Keys, Ancel, Josef Brozek, Austin Henschel, O. Michelson, et al. 1950. The Biology of Human Starvation. University of Minnesota Press.
41 Barbara Hansen, the director of the Obesity Research Center at the University of Maryland School of Medicine, conducted the study of weight loss and gain among monkeys. She describes the study in which she forced monkeys to lose weight and stay on a diet for two years and then, when she took them off of the diet they regained their weight, in the excellent book: Vogel, S. 1999. The Skinny on Fat. W.H. Freeman and Company. (See page 110).
41 For a current discussion of the set point theory of human weight, see the special issue of Nature devoted to Obesity -- 6 April 2000. Obesity Special Issue. Nature 404.

For a more accessible, but less current, discussion see Gibbs, Wayt. 1996. "Gaining on Fat." Scientific American August. Available online at:
41 The study that measured metabolic rate during weight loss and weight gain of 10% is, Leibel, Rudolph, Michael Rosenbaum and Jules Hirsch. 1995. "Changes in Energy Expenditure Resulting from Altered Body Weight." New England Journal of Medicine, March 9 332(10): 621-628.
42 The role of neuropeptide Y in the control of appetite is described in Jhanwar-Uniyal, M., B. Beck, Y.S. Jhanwar, C. Burlet, and S.F. Leibowitz. 1993. "Neuropeptide Y projection from arcuate nucleus to parvocellular division of paraventricular nucleus: specific relation to the ingestion of carbohydrate." Brain Research 631:97-106. They found that a strong, positive correlation was found between daily carbohydrate intake and hypothalamic NPY levels.
42 As they get hungrier and hungrier, lab animals do indeed lose their sex drive. Data are from: Stone, C. P. and L. Ferguson. 1938. "Preferential responses of male albino rats to food and to receptive females." Journal of Comparative Psychology 26:237-255.
43 Numerous studies of the placebo effect have been noted over the year. The Xenical study cited is from Aronne, L.S. 1998. "Modern medical management if obesity: the role of pharmaceutical intervention." Journal of the American Dietetic Association 98:23-26. "In a one-year placebo-controlled study, 55% of patients getting Xenical lost more than 5% of their body weight, and 25% lost more than 10% of their body weight (compared with 33% and 15% in the placebo group)."
43 The strategies of successful dieters are recounted in: McGuire, M.T., R.R.Wing, M.L. Klem, W. Lang and J.O. Hill. 1999. "What predicts weight regain in a group of successful weight losers?" Journal of Consulting and Clinical Psychology 67:177-185; See also Klem, M.L., R.R. Wing, M.T. McGuire, H.M. Seagle, and J.O. Hill. 1998. "Psychological symptoms in individuals successful at long-term maintenance of weight loss." Health Psychology 17:336-345.

The Socrates quote comes from Plato's Apology of Socrates. On trial for his life, Socrates says (as written by Plato),

"I have no wisdom, small or great. What then can he mean when he says that I am the wisest of men? … So I left him, saying to myself, as I went away: conceit of Man, although I do not suppose that either of us knows anything really beautiful and good, I am better off than he is, for he knows nothing, and thinks that he knows; I neither know nor think that I know."

There are many versions of the Apology of Socrates still in print. One inexpensive and easy to find version is the Penguin classic - The Last Days of Socrates.


A short article containing the highlights of the Peter Maher story is available online at:

Maher ran his Personal best of 2:11 in the 1991 London marathon. He is listed among the fastest marathon runners of all time at:

48 We encountered the mice that wouldn't exercise in the course of Jay's dissertation research: Phelan, J.P. 1995. Reproductive Costs and Longevity in the House Mouse. Ph.D. Dissertation, Harvard University.
49 Natasha, the chimp that hates to move, was coaxed across her compound by oranges thrown just out of her reach by Terry, at Yerkes Regional Primate Research Center in Atlanta during the summer of 1998.
50 Data on wheel running distances for hungry vs. satiated mice are also from Jay's dissertation research: Phelan, J.P. 1995. Reproductive Costs and Longevity in the House Mouse. Ph.D. Dissertation, Harvard University.
50 The ingenious mouse cage in which the animals must run some pre-determined number of revolutions on their exercise wheel before they'll get any food was invented and built by Glenn Perrigo. It's use is described in numerous excellent papers including: Perrigo, G. and F.H. Bronson. 1983. "Foraging effort, food intake, fat deposition and puberty in female mice." Biology of Reproduction 29:455-463; and Perrigo, G. and F.H. Bronson. 1985. "Behavioral and physiological responses of female house mice to foraging variation." Physiology & Behavior 34:437-440.
51 People who paid full price for their theater season tickets compared with those who were given theirs for half price. The experiement is described in: Arkes, H. and C. Blumer 1985. "The psychology of sunk costs." Organizational Behavior and Human Decision Processes 35:124-140.

Some online data on olestra:, and


The corporate website from the producer of nutrasweet:

54 Fake sugars don't fool your body into thinking that it has eaten sugary foods. The data are presented in: Lavin, J.H., S.J. French, and N.W. Read. 1997. "The effect of sucrose and aspartame-sweetened drinks on energy intake, hunger, and food choice of female, moderately restrained eaters." International Journal of Obesity 21:37-42.
54 The successful use stomach banding for long-term weight loss is described in: O'Brien, P.E., W.A. Brown, A. Smith, P.J. McMurrick, and M. Stephens. 1999. "Prospective study of a laparoscopically placed, adjustable gastric band in the treatment of morbid obesity." British Journal of Surgery 86:113-118.
55 Data on the number of liposuction procedures performed are presented at:

Recent studies of diet drugs and heart disease include:

Jick, H., C. Vasilakis, L. Weinrich, C. Meier, et al. 1998. "A population-based study of appetite-suppressant drugs and the risk of cardiac-valve regurgitation." New England Journal of Medicine 339(11): 719-24.

Kancherla, M., T. Mulderink, M. Parker, R. Bonow, et al. 1999. "Echocardiographic prevalence of mitral and/or aortic regurgitation in patients exposed to either fenfluramine-phentermine combination or to dexfenfluramine." American Journal of Cardiology. 84(11): 1335-8.


55 Fen-Phen weight loss over time and health, Wadden, T., R. Berkowitz, F. Silvestry, R. Vogt, et al. 1998. "The fen-phen finale: a study of weight loss and valvular heart disease." Obesity Research 6(4): 278-84.

Fen-Phen usage rates and discussion of disease implications available online from the American Medical Association at:

55 The U.S. FDA official publication about liposuction states, "Liposuction is for body contouring, recommended for people who want to remove small amounts of fatty deposits." See full article online:
55 The claims of Metabolife for increasing the expenditure of energy without an offsetting increase in appetite are made at:, while the claims made for ephedrine and caffeine-based products are described at:
55 For the current market price of a 3-month supply of Xenical, go to:

A study of Xenical/Orlistat in combination with traditional dieting, concludes that,

"The use of orlistat during periods of attempted weight maintenance minimizes weight readjustment and facilitates long-term improvement in obesity-related disease risk factors."

Hill, J. , J. Hauptman, J. Anderson, K. Fujioka, et al. 1999. "Orlistat, a lipase inhibitor, for weight maintenance after conventional dieting: a 1-y study." American Journal of Clinical Nutrition 69(6): 1061-3.

55 The successful use of Xenical/Orlistat was described in 1999 in three articles in the Canadian Family Physician: Vol: 45:2331-3, 2336-8, 2343-5.

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Drugs: Hijacking the pleasure pathway

John Daly discussed his ongoing battle over trying to stay sober with ESPN Golf Online news services September 23, 1999 and in a related interview with Golf World Magazine. Excerpts.

NEW YORK -- John Daly is drinking and gambling again, not sure where it will lead but offering no regrets for losing an endorsement with Callaway Golf that had been his primary source of income. "It's sad, but I think it's great to be free," Daly told Golf World magazine
".. there's no sense in denying it. It's in my blood."

Daly said "Basically, it (trying to stay sober) had taken over my life, and I was miserable. It's like I've said before, there's no way I'd never drink again."

Daly's five-year deal with Callaway, signed after he left rehab in April 1997, included a provision that he not drink or gamble. Chairman Ely Callaway offered to send Daly to an addictions specialist nearly two weeks ago. Daly got to the undisclosed clinic and left. "The people were nice," Daly told Golf World. "But it just wasn't for me." Callaway said he had no choice but to drop Daly, who stood to earn about $3 million over the final two years of the contract.

Asked by the magazine why he continued to gamble even though he lost an estimated $12 million from 1993 to 1996, Daly said, "I love the action. I just love it."

59 Janis Joplin's "love affair" with drugs recounted in, Ward, Ed, Geoffrey Stokes and Ken Tucker. 1986. Rock of Ages: The Rolling Stone History of Rock and Roll.
59 Data from the Centers for Disease Control on the destructive toll of alcohol use, are given at:; The tally includes 25,175 deaths in the United States from chronic liver disease and cirrhosis in 1997 (the 10th leading cause of death in the United States that year). See also: for a sobering summary of data collected by the National Institutes of Health.
60 The U.S. Department of Justice reported in April 1998 that in nearly 40 percent of violent crimes, alcohol is a factor, including in three-fourths of reported cases of spouse violence.
60 Relative mortality from traffic accidents and smoking: According to the National Highway Traffic Safety Administration there were 41, 471 traffic fatalities in 1998. According to the Food and Agricultural Organization of the United Nations, about 500,000 North Americans and 2.5 million people worldwide die from cigarette smoking every year.
60 A good review of the literature on the addictive capacity of chemicals, including a description of the extent of animals' powerful desire to self-administer cocaine is: Gardner, E.L. and J. David. 1999. "The neurobiology of chemical addiction." In Elster, J. and O.J. Skog (eds), Getting Hooked: Rationality and the Addictions. Cambridge University Press. (See pages 93-136.)
60 Data on the worldwide consumption of caffeinated beverages are from: Graham, H.N. 1984. "Tea: the plant and its manufacture: chemistry and consumption of the beverage" and Gilbert, R.M.1984. Caffeine consumption. Both in: Spiller, G.A. (ed), The Methylxanthine Beverages and Foods: Chemistry, Consumption and Health Effects. Liss Publishing.
61 The data on improved maze-learning among rats after they have consumed caffeine are from: Battig, K., and H.Wetzl. 1993. "Psychopharmacological profile of caffeine." In Caffeine, Coffee, and Health, edited by S. Garrattini. Raven Publishing.
61 The benefits to competitive cyclists of caffeine consumption are described in: Burke, E.R. 1992. Cycling health and Physiology. Vitesse Press.
61 Numerous studies have searched for negative long-term health consequences of caffeine consumption with no significant findings. For one summary, see Chou, T. 1992. "Wake up and smell the coffee: Caffeine, coffee and medical consequences." Western Journal of Medicine 157:544-554. Numerous questions remain to be answered, though, as discussed in Goldstein, A. 1994. Addiction, from Biology to Drug Policy. W.H. Freeman and Co.
62 The mechanism by which adenosine may influence sleep and wakefulness is described in the review article: Porkka-Heiskanen, T. 1999. "Adenosine in sleep and wakefulness." Annals of Medicine 2:125-9. A less technical but really excellent description is given in: Braun, S. 1996. Buzz: The Science and Lore of Alcohol and Caffeine. Penguin Books.
63 James Olds's demonstration that rats loved stimulation (with electrodes) in the mesolimbic area of their brain is described in: Olds, J. "'Reward' from brain stimulation in the rat." Science 122:878. For an interesting and personal description of this important research, see:
66 For a description of the relationship between genital stimulation, erections, and brain sensations of pleasure, see: Hirayama, A., K. Yamada, Y. Tanaka, N. Hirata, M. Yamamoto, T. Suemori, H. Momose, T. Shiomi, S. Oozono and Y. Hirao, 1995. "Evaluation of sexual function in adults with myelomeningocele." Acta Urologica Japonica 41:985-9.
68 The dramatic effect of endorphins on mood are described in: Wildmann, J. A. Krueger, M. Schmole, J. Niemann, and others. 1986. "Increase of circulating beta-endorphin-like immunoreactivity correlates with the change in feeling of pleasantness after running." Life Sciences 38:997-1003.
69 An accessible description of the physiological effects of nicotine are described: Krogh, D. 1991. Smoking: The Artificial Passion. W.H. Freeman and Co. (See page 32.) See also: DiChara, G. and A. Imperato. 1988. "Drugs abused by humans preferentially increase synaptic dopamine concentrations in the mesolimbic system of freely moving rats." Proceedings of the National Academy of Sciences 85:5274-78.
70 A lucid account of the neurochemical consequences of alcohol in the brain is given in: Braun, S. 1996. Buzz: The Science and Lore of Alcohol and Caffeine. Penguin Books. See also: Weight, F.F. 1992. Cellular and molecular physiology of alcohol actions in the nervous system. International Review of Neurobiology 33:289-348; and Gianoulakis, C., P. Angelogianni, M. Meany, J. Thavundayil, and V. Tawar. 1990. "Endorphins in individuals with high and low risk for development of alcoholism." In: Opioids, Bulemia, and Alcohol Abuse and Alcoholism, L. D. Reid (ed.). Springer-Verlag.
70 The serotonin increasing, Prozac-like qualities of alcohol are described in: Lovinger, D.M. and R.W. Peoples. 1993. Actions of alcohols and other sedative/hypnotic compounds on cation channels associated with glutamate and 5-HT3 receptors. In: Alcohol, Cell Membranes, and Signal Transduction in Brain, C. Alling, I. Diamond, S.W. Leslie (eds.). Plenum Press.
71 It is difficult to get an accurate count of just how many high school students take steroids and so estimates can vary a bit. The data we cite are from the National Institute of Drug Abuse ( they reported in 1997 that 175,000 high school girls and 325,000 high school boys used steroids.
71 Anabolic steroids can indeed increase an individual's muscle mass. According to The National Clearinghouse for Alcohol and Drug Information: "Anabolic steroids are drugs derived from the male sex hormone, testosterone. They promote muscle growth and increase lean body mass." See:
71 In addition to their desired effects, steroid have numerous dangerous effects in males, including shrinking of the testicles, reduced sperm count, infertility, baldness, development of breasts. For a detailed description, see the National Institutes of Health's summary at:
72 Data on caffeine consumption in the U.S. and the amount of caffeine in soda are from: Nehlig, A. 1999. "Are we dependent upon coffee and caffeine? A review on animal and human data." Neuroscience and Biobehavioral Reviews 23:563-576. (See page 564: "Caffeine consumption reaches 210-238 mg/day in the U.S.")
72 The study in which subjects were given 900mg of caffeine a day for three weeks is: Evans, S.M. and R.R. Griffiths. 1992. "Caffeine tolerance and choice in humans." Psychopharmacology 108:51-59.
72 Heroin tolerance study reported in, Jones, Kenneth Lamar, Louis W. Shainberg and Curtis O. Byer. 1979. Drugs and Alcohol. 3rd Edition. Harper & Row. (p. 31). "A group of individuals were given equal doses of heroin every day for 19 days. The euphoric effects (exaggerated sense of well-being) they experienced after receiving the heroin were measured each day and graphed. The effects of the standard dosage decreased and by the 19th day were almost nonexistent.")
73 Alcohol withdrawal varies tremendously from person to person and can include many symptoms from tremors, sweating, and insomnia, to full-blown delirium tremens. In fewer than 5% of cases, does alcohol withdrawal progress to delirium tremens. For a detailed discussion , see Madden, J.S. 1984. A Guide to Alcohol and Drug Dependence. Bristol publishing. (See pages 44-45.)
74 The chemical details of the fast flushing response are given in: Institute of Medicine. 1997. "The Neurobiology of Addiction: An Overview." In: Dispelling the Myths About Addiction : Strategies to Increase Understanding and Strengthen Research Institute of Medicine (eds.). National Academy Press. See pages 37-54.
74 The increased incidence of fast flushing among Asians is described in: Chen, C.C. and E.K. Yeh. 1989. "Population differences in ALDH levels and the flushing response." In: Molecular Mechanisms of Alcohol, G.Y. Sun (ed.). Humana Press.
74 Data on the lack of fast flushing among Japanese alcoholics is from: Higuci, S., S. Matsushita, H. Imazeki, T. Kinoshita, S. Takagi, and H. Kono. 1994. "Aldehyde dehydrogenase genotypes in Japanese alcoholics." Lancet 343:741-742.
74 The breeding of animals that liked the taste of alcohol is described in: Crabbe, J.C., J.K. Belknap, and K.J. Buck. 1994. "Genetic animal models of alcohol and drug abuse." Science 264:1715-1723. Their brains were shown to have decreased serotonin levels in: Murphy, J.M., W.J. McBride, L. Lumeng, and T.K. Li. 1987. "Contents of monoamines in forebrain regions of alcohol-preferring and non-preferring lines of rats." Pharmacology, Biochemistry and Behavior 26:389-392.

Are dopamine receptor levels related to alcoholism? This is still a pretty controversial question. Examination of DNA samples from the brains of corpses of thirty-five alcoholics and thirty-five non-alcoholics revealed that a variant of the gene for a specific type of dopamine receptor (D2) was present in 69% of the alcoholics but only 20% of the non-alcoholics. These date are from: Noble, E.P., P.J. Sheridan, A. Montgomery, T. Ritchie, P. Jagadeeswaran, H. Nogami, A.H. Briggs, and J.B. Cohn. 1990. "Allelic association of the D2 dopamine receptor gene in alcoholism." Journal of the American Medical Association 263:2055-60; and also discussed in: Noble, E.P. and K. Blum. 1991. "The dopamine D2 receptor gene and alcoholism" (letter to the editor). Journal of the American Medical Association 265:2667.

Their claim is that this variant, called the A1 allele, results in fewer D2 receptors in the brain (See Noble, E.P., K. Blum, T. Ritchie, A. Montgomery, and P.J. Sheridan, P.J. 1991. "Allelic association of the D2 dopamine receptor gene with receptor binding characteristics in alcoholism." Archives of General Psychiatry 48:648-654.) In this paper, the second section of table 3, page 652, clearly shows that the number of binding sites is significantly correlated with which allele a person carries.

On the front page of the New York Times, however, a team from the National Institute on Alcohol Abuse and Alcoholism announced that it did not find any difference between alcoholics and non-alcoholics in the frequency of the A1 allele. Both sides are continuing to explore this issue.


Also controversial is the question of the link between having a gene for dopamine receptors and smoking addiction. But see: Lerman, C., N.E. Caporaso, J. Audrain, D. Main, E.D. Bowman, B. Lockshin, N.R. Boyd, and P.G. Shields. 1999. "Evidence suggesting the role of specific genetic factors in cigarette smoking." Health Psychology 18:14-20. This was a twin study showing evidence that the SLC6A3 (dopamine receptor) gene influenced smoking initiation and nicotine dependence.

Another study then proposed that that individuals with a particular type of dopamine receptor gene have altered dopamine transmission, reducing their need for novelty and reward by external stimuli (such as cigarettes). See: Sabol, S.Z., M.L. Nelson, C. Fisher, L. Gunzerath, C.L. Brody, S. Hu, L.A. Sirota, S.E. Marcus, B.D. Greenberg, F.R. Lucas, J. Benjamin, D.L. Murphy, and D.H. Hamer. 1999. "A genetic association for cigarette smoking behavior." Health Psychology 18:7-13.

75 The link between drug addictions and the body's dopamine system is discussed in: Noble, E.P., K. Blum, M.E. Khalsa, T. Ritchie, A. Montgomery, R.C. Wood, R.J. Fitch, T. Ozkaragoz, P.J. Sheridan, M.D. Anglin, and others 1993. "Allelic association of the D2 dopamine receptor gene with cocaine dependence." Drug and Alcohol Dependence 33:271-85.
75 Thomas Richard Jones's attorney described his clients battle with alcohol and pills in his closing argument: "The devil lurking in this alcohol and in these pills would not turn loose of him." From: Vick, K. 1997. "Intoxicated N.C. Driver Handed Life Sentence." Washington Post, 5/7/97, p. A9.
76 In male identical twins, the concordance rate for alcoholism is was measured as 76% versus 61% for fraternal twins. Among females, the numbers were 36% and 25%, respectively. See: Pickens, R.W., D.S. Svikis, M. McGue, D.T. Lykken, L.L. Hesten, and P.J. Clayton. 1991. "Heterogeneity in the inheritance of alcoholism." Archives of General Psychiatry 48:19-28.
77 John Daly's 3 million dollar drink. Daly walked away from a $3 million contract that required him to stay sober. See detailed note for page 59 (above) for source and quote.

Thomas Covington featured in New York Times, September 19, 1999. Excerpts,

A Drug Ran Its Course, Then Hid With Its Users

"I don't think anything the police did changed my behavior," said Thomas Covington, who was arrested 31 times, mostly for crack possession, and served two prison terms before voluntarily entering drug treatment. "Sometimes it was a little more challenging to buy. But once that compulsion is there, it doesn't matter what the penalty or the threat is."

Covington is a big, sharp-witted Brooklyn native who has used crack on and off for 15 years. He made it through the explosive violence that came with crack's introduction. He was homeless, and sick, and twice felt the steel tip of a handgun pressed to his temple by hot-tempered dealers.

He dodged the police offensives of three mayors.

But starting in the early 90's, Covington said, he noticed a shift in the attitudes of young drug dealers. "They didn't use crack," he said. "And they didn't respect people who did. To me, being a 34- or 35-year-old guy, standing on line and handing my money to a 15-year-old, that was humiliating."

78 Data on the ancient use of hallucinogenic compounds by the Maya are from: Stone, T. and G. Darlington. 2000. Pills, Potions and Poisons: How Drugs Work. Oxford University Press.
80 For good general descriptions of the physiological effects of anti-alcohol drugs, see: and
80 The cocaine-fighting chemical, BP 897, was described in detail in the news article: Aston-Jones, G. and Druhan, J. 1999. "Breaking the chain of addiction." Nature 9/16/99.

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Risk: Thrill-seeking genes take us for a ride

U.S. gambling statistics are available in many places. The most comprehensive is the 1999 report of the National Gambling Impact Study Commission—available online: The Economist wrote a more readable article on U.S. gambling in June 1998, it's highlights:

"Legalised gambling is now permitted in 47 states and the District of Columbia, generating more than $50 billion in gross revenues (dollars wagered minus payouts). Gambling expenditures as a percentage of personal income more than doubled between 1974 and 1997, from 0.3% to 0.74%. Americans now spend more on various wagers than they do on theme parks, video games, spectator sports and movie tickets combined (see chart). Government is far more than an observer in all this. Revenue from state lotteries climbed from $2 billion in 1973 to $34 billion in 1997. The states spent $400m advertising such games, in some cases targeting poor districts. Tribal casinos take in another $7 billion."


California lottery rules:
What is SuperLottoTM? SuperLotto is your chance to win millions of dollars! The jackpot ranges from $4 million to $50 million or more. The jackpot rolls over and grows whenever there is no winner. All you have to do is pick six numbers from 1 to 51 and match them to the six numbers drawn by the Lottery every Wednesday and Saturday.

In the lottery, there are 51 balls, each with a different number painted on. They go from 1 to 51. Six balls are going to be pulled out of a bin. In order to win the jackpot, you must choose all six numbers.

85 The HIV test problem and the results from the Harvard Medical School are reported in, Casscells, W., A. Schoenberger and T. Grayboys. 1978. "Interpretation by physicians of clinical laboratory results." New England Journal of Medicine 299: 999-1000.
86 More than twice as many people lose their lives in automobile accidents each year than have died in airline crashes in the entire history of air travel. Glassner, Barry. 1999. The Culture of Fear: Why Americans Are Afraid of the Wrong Things. Basic Books.
86 Red deer stag competition described in, Clutton-Brock, T.H. and S.D. Albon. 1979. "The roaring of red deer and the evolution of honest advertisement." Behaviour, 69: 145-70. See also Krebs and Davies. 1993. An Introduction to Behavioral Ecology, 3rd edition. Blackwell Scientific Publications. P 160-161 for a succinct summary and p 162 for photographs of stags bellowing, parallel walking and fighting (figure 7.5).
87 Mini and Hulkster battle in, Austad, S. N. 1983. "A Game Theoretical interpretation of male combat in the bowl and doily spider, Frontinella pyramitela." Animal Behavior 31: 59-73.

Yanomamö unokais data from, Chagnon, Napolean. 1988. "Life Histories, Blood Revenge, and Warfare in a Tribal Population." Science 239: 985-992. General discussion of the Yanomamö in, Chagnon, Napoleon. 1992. Yanomamö, 4th edition. Harcourt Brace Jovanovich.

Unokais -- 137 men in this study were Unokai (had killed another man)

Average number of living offspring = 4.91
Average number of wives = 1.63

Non-unokais -- 243 men in this study were not Unokai (had not killed another man)

Average number of living offspring = 1.59
Average number of wives = 0.63


Dopamine receptors (the "novelty gene") and risky behavior, Benjamin, J., L. Li, C. Patterson, B.D. Greenberg, et al. 1996. "Population and Familial Association Between the D4 Dopamine Receptor Gene and Measures of Novelty Seeking." Nature Genetics 12: 81-4. The last author of this study is Dean Hamer, who wrote, Hamer, Dean. 1998. Living with our Genes. Doubleday. In it he discussed the relationship between the novelty gene and sex:

"Straight [heterosexual] men with the long gene, the high novelty seekers, were six time more likely to have slept with another man than those [heterosexual men] with a short gene... Those [gay men] with the long, high novelty-seeking form of the gene had sex with more than five times as many women as did those with the shor, low novelty-seeking form." -- p. 179-180.

89 The "novelty gene" and migration, Chen, Chuansheng, Michael Burton, Ellen Greenberger and Julia Dmitrevea. 1999. "Population Migration and the Variation of Dopamine D4 Receptor (DRD4) Allele Frequencies Around the Globe." Evolution and Human Behavior, September 20(5): 309-324.
91 Brilliant woodpecker statisticians, Lima, Steve. 1984. "Downy woodpecker foraging behavior: efficient sampling in simple stochastic environments." Ecology 67: 377-85.
92 U.S. mortality figures (1997) from the Centers for Disease Control, National Vital Statistics Reports. Volume 47, Number 19, Deaths Final Data for 1997, available online:
92 An excellent article on what Americans fear and what we actually die from is, Slovic, Paul , Baruch Fischhoff and Sarah Lichtenstein. 1982. Chapter 33: Facts vs. fears: Understanding perceived risk. in Daniel Kahneman, Paul Slovic and Amos Tversky, eds., Judgment under Uncertainty: Heuristics and Biases.: Cambridge University Press.
93 Ache death figures from Hill, Kim and Magdelena Hurtado. 1996. Ache Life History: The Ecology and Demography of a Foraging People. Aline De Gruyter. See pages 172-173.
96 Humans inability to figure the odds for problems of the sort used by the California lottery, Kahneman, Daniel, Paul Slovic and Amos Tversky, Eds. 1982. Judgment under Uncertainty: Heuristics and biases. P 169.
97 Lottery tickets study and the bumbling vs. competent opponent study are both described in, Langer, Ellen J. 1982. Chapter 16: The Illusion of Control. in Daniel Kahneman, Paul Slovic and Amos Tversky, eds., Judgment under Uncertainty: Heuristics and Biases.: Cambridge University Press.

The definitive source for U.S. Stock market data is, Siegel, Jeremy J. 1998. Stocks for the Long Run, 2nd edition. McGraw-Hill.

"over the last century, accumulations in stocks have always outperformed other financial assets for the patient investor. Even such calamitous events such as the Great 1929 Stock Crash did not negate the superiority of stocks as long-term investments." --p. 5

102 A paper showing that people, particularly men, who trade actively do worse than those who trade less frequently, Barber, Brad M. and Terrance Odean. 2000. "Boys Will Be Boys: Gender, Overconfidence, and Common Stock Investment." Quarterly Journal of Economics Forthcoming. Preprint available for download

Iceman museum online

The Iceman after a risky career change

104 Sir Edmund Hilary online (with video)

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Greed: Running fast on the happiness treadmill
An excellent discussion of the lack of long-term satisfaction achieved through wealth is contained in the opening chapter of, Frank, Robert. 1999. Luxury Fever. Why Money Fails to Satisfy in an Era of Excess. The Free Press.
105 An academic work on the causes of happiness is, Kahneman, Daniel, Ed Diener and Norbert Schwarz, Eds. 1999. Well-Being: The Foundations of Hedonic Psychology. Russell Sage Foundation. In Chapter 18, causes and correlates of happiness, Michael Argyle discusses the role of money in happiness and states, "Income has a complex and generally weak effects on happiness. Cross-sectional studies find a small positive effect but only at the lower end of the income scale" --p 353
107 The official suicide statistics for the United States are compiled by the Centers for Disease Control and available online:
107 A recent book on suicide is, Jamison, Redfield. 1999. Night Falls Fast. Knopf. --Some key data from the book: Suicide attempts land half a million Americans in hospitals every year. As compiled by the World Health Organization (WHO), 2 percent of deaths in 1998 were suicides -- more than from war and far more than from homicide.
107 Depression statistics from, Kessler RC, McGonagle KA, Swartz M, Blazer DG, Nelson CB. "Sex and depression in the National Co-morbidity Survey. I: Lifetime prevalence, chronicity and recurrence." J Affect Disord. 1993;29:85-96.

Life among the Yanomamo (before their civilization was destroyed) is discussed in, Chagnon, Napoleon. 1992. Yanomamo, 4th edition. Harcourt Brace Jovanovich.

"I would be bitterly disappointed that my erstwhile friend thought no more of me than to finesse our personal relationship exclusively with the intention of getting at my locked up possessions, and my depression would hit new lows every time I discovered this. ... The hardest thing to learn to live with was the incessant, passioned, and often aggressive demands they would make." --p 16

"by then, a species of insect has laid its eggs in the pith and the eggs have developed into large grubs, some the size of mice! This grub looks like a housefly maggot, but a very large one. ...An experienced missionary who tried them said they taste to him like very fat bacon"-- p 62

109 The famous lottery winners and accident victims paper is, Brickman, P., D. Coates and R.J. Janoff-Bulman. 1978. "Lottery Winners and Accident Victims: Is Happiness Relative?" Journal of Personality and Social Psychology 36: 917-927.
110 Reeve, Christopher. 1998. Still Me. Ballantine.
112 In an e-mail to us from Graceland, the Graceland museum informed us that: "Elvis took a few friends from Memphis to Denver and back for peanut butter and banana sandwiches from a restaurant there. His 'Lisa Marie' jet airplane was a Delta airliner at one time and held 96 passengers before he converted it to his 'flying Graceland'. It is a Convair 880. It took 2200 gal. of fuel to take off and burned 1,700 gal. per hour flying."
112 Well-fed opossums running on the happiness treadmill are from, Austad, S.N. and M.E. Sunquist. 1986. "Sex-ratio manipulation in the Common Opossum." Nature 324: 58-60.

Jim Clark stories from, Lewis, Michael. 1999. The New New Thing. Norton.

I reminded Clark that he had said that once he became a real, after-tax billionaire he'd retire. He now said, without missing a beat: "I just want to make more money than Larry Ellison. Then I'll stop." This was news. I pointed out that he'd never before mentioned this ambition. "I just want to have more money than Larry Ellison," he said again. "I don't know why. But once I have more money than Larry Ellison I'll be satisfied."

Larry Ellison, the C.E.O. of Oracle, the biggest software company in the valley, was worth about $9 billion; Clark was, just then, worth a bit more than $3 billion. On the other hand, Ellison's wealth was completely tied up in Oracle stock, which had mostly missed out on the Internet boom. At the rate Clark's wealth was growing he'd pass Ellison within six months. I pointed this out and asked the obvious question:

"What happens after you have more than Larry Ellison? Would you want to have more money than, say, Bill Gates?... Oh, no," Clark said, waving my question to the side of the room where the ridiculous ideas gather to commiserate with one another. "That'll never happen." A few minutes later, after the conversation had turned to other matters, he came clean. "You know," he said, "just for one moment, I would kind of like to have the most. Just for one tiny moment."


Charlie Brown chasing elusive goals:


Birth amnesia is described in, McKay, S. and T.L. Barrows. 1992. "Reliving birth: maternal responses to viewing videotape of their second stage labors." The Journal of Nursing Scholarship, Spring 24(1): 27-31.

"Often women found the videotape viewing to be intensely emotional, especially when they heard noises they made. Women frequently commented upon details they hadn't remembered, their reactivated memory for labor pain, and the 'weird' experience of watching themselves in labor."


An excellent discussion on the evolution of greed is contained within, Hill, Kim and Magdelena Hurtado. 1996. Ache Life History: The Ecology and Demography of a Foraging People. Aline De Gruyter.

"The Ache eat better than almost any other group of foragers ever studied and they weigh considerably more than well-known groups such as the !Kung, yet data clearly indicate that they do not get 'enough food to meet their needs.' More food is shown to impact positively on fertility of both sexes and may also increase child survival (though the evidence is weak)." --p 319

121 The ice water study, Kahneman, D., B. L. Fredrickson, C. A. Schreiber and D. A. Redlemeier. 1993. "When more pain is preferred to less: Adding a better end." Psychological Science 4: 401-405.
121 The colonoscopy study, Katz, J., D. A. Redelmeier and D. Kahneman. 1996. "Memories of painful medical procedures." Fifteenth annual scientific meeting of the American Pain Society, Washington (November 14-17, 1996).
122 Solzhenitsyn, Alexander. 1962. One Day in the Life of Ivan Denisovich. Signet Classic.
123 The dime in the photocopier study, Schwarz, Norbert. 1987. Stimmung als Information : Untersuchungen zum Einfluss von Stimmungen auf die Bewertung des eigenen Lebens. Springer. pp 12-13. (Note, this text is in German.)

Hemingway, Ernest. 1984. Ernest Hemingway on Writing. Simon and Schuster.

"How much should you write a day? The best way is always to stop when you are going good and when you know what will happen next. If you do that every day when you are writing a novel you will never be stuck." --p 42


The master of happiness discusses flow in, Csikszentmihalyi, Mihaly. 1990. Flow: the Psychology of Optimal Experience. Harper & Row.

"Thus we have the paradoxical situation: On the job people feel skillful and challenged, and therefore feel more happy, strong, creative, and satisfied, In their free time people feel that there is generally not much to do and their skills are not being used, and therefore they tend to feel more sad, weak, dull, and dissatisfied. Yet they like to work less and spend more time in leisure." -- p 159


Twilight Zone episode "A NICE PLACE TO VISIT" avaiable online:

While committing a crime, a cheap hood (Blyden) gets killed and finds an afterlife in which all wishes are granted.

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Gender: Girls against the boys
The classic study showing that most male college students and no female college students are willing to have sex when proposed by a member of the opposite sex (of average attractiveness) is: Clark, R.D. and E. Hatfield. 1989. "Gender differences in receptivity to sexual offers." Journal of Psychology & Human Sexuality 2:39-55.
133 Read the 19th amendment and learn more about it at:
133 For info on women's marathon records, go to:
134 To put human sex differences in size, see: Jolly, A. 1985. The Evolution of Primate Behavior 2nd edition. Macmillan. She concludes (page 251) that "The weight differences between human males and females fall into 'mildly polygynous' class."
134 For a summary of male female physical differences, see Baker, M.A. (ed). 1987. Sex Differences in Human Performance. John Wiley.
134 Data on the increasing differences in throwing ability with age are from: Thomas, J.R. and K.E. French. 1985. "Gender differences across age in motor performance: A meta-analysis." Psychological Bulletin 98:260-282.
134 Sex differences in bone size are presented in: Gindhart. P.S. 1973. "Growth standards for the tibia and radius in children aged one month through eighteen years." American Journal of Physical Anthropology 39:41-48; and Tanner, J.M. 1990. Foetus into Man: Physical Growth from Conception to Maturity. Harvard University Press.
135 An excellent discussion of the great disparity in average life span for men and women around the world is: Austad, S.N. 1997. Why We Age. John Wiley & Sons.
135 The data showing increased longevity resulting from castration are from: Hamilton, J.B. and G.E. Mestler. 1969. "Mortality and survival: comparison of eunuchs with intact men and women in a mentally retarded population." Journal of Gerontology 24:395-411.
136 Cats and dogs live longer if they are neutered, too: Bronson, R.T. 1981. "Age at death of necropsied intact and neutered cats." American Journal of Veterinary Research 42:1606-1608; Bronson, R.T. 1982. "Variation in age at death of dogs of different sexes and breeds." American Journal of Veterinary Research 43:2057-2059.
136 According to the Justice Department, U.S. adult prisons and jails held 1.82 million inmates in 1998. See for additional information.
136 Data on the absence of a significant sex difference in gun use during crimes comes from Campbell, A. 1993. Men, Women and Aggression. Basic Books.
136 The study of sex differences in language recovery in aphasia is: Pizzamiglio, L., A. Mammucari, and C. Razzano. 1985. "Evidence for sex differences in brain organization in recovery in aphasia." Brain & Language 25:213-223.
136 Differences in men's and women's verbal dexterity are described in: Pugh, K., B. Shaywitz, T. Constable, S. Shaywitz, P. Skudlarski, R. Fullbright, R. Bronen, D. Shankweiler, L. Katz, J. Fletcher, and J. Gore. 1996. "Cerebral organization of component processes in reading." Brain 119:1221-1238; and K. Pugh, B. Shaywitz, S. Shaywitz, D. Shankweiler, L. Katz, J. Fletcher, T. Constable, P. Skudlarski, R. Fullbright, R. Bronen, and J. Gore. 1997. "Predicting reading performance from neuroimaging profiles: The relation between phonological effects and the cerebral organization of phonological processing." Journal of Experimental Psychology: Human Perception and Performance 23:299-318.
138 For an interesting account of Saharan gerbil behavior see: Daly, M. and Daly, S. 1974. "Spatial distribution of a leaf-eating Saharan gerbil (Psammomys obesus) in relation to its food." Mammalia 38:591-603.
139 A related study that highlights sex differences in predation risk, showing males to have double the predation risk of females, but only during the breeding season, is: Daly, M., M. Wilson, P.R. Behrends, and L.F. Jacobs. 1990. "Characteristics of kangaroo rats, Dipodomys merriami, associated with differential predation risk." Animal Behaviour 40:380-389.
139 The high-volume natterjack choruses are described in: Arak, A. 1988. "Callers and satellites in the natterjack toad: evolutionarily stable decision rules." Animal Behaviour 36:416-432; and Arak, A. 1983. "Sexual selection by male-male competition in natterjack toad choruses." Nature 306:261-2.
139 Two excellent sources of information about phalaropes can be found in: and Reynolds, J.D. 1987. "Mating system and nesting biology of the red-necked phalarope, Phalaropus lobatus: what constrains polyandry?" Ibis 129:225-242.

Seahorses as Mr. Moms.

Many books suggest that seahorses display sex role reversals similar to that of moorhens; recent data suggest that this may not be true, at least for some species. Note: seahorses are fish complete with fins and gills.

The story until recently focused on the high level of male seahorse investment in offspring. The seahorse mating system has females produce the eggs then transfer them to a pouch in the male. The male carries the offspring inside of him in a form of prenancy and eventually gives birth. The link has some interesting photos of seahorses and contains a review of the literature.

There is also a nice National Geographic article (with great photos) on seahorses:
The improbable seahorse. 1994 National Geographic 186 (October) :126

Recent data suggest that male seahorses do not invest more in offspring than do female seahorses. In this new view, the male investment in offspring is still considered high, but females invest significant resources in egg production and females (at least of some species) visit males during the males "pregnancy".

If male seahorse investment in offspring is lower than female investment in offspring, then the prediction is that seahorses will display the more common sex differences in behavior. Specifically, if females invest more, the females should be more choosy in picking mates than males, and males will be more competitive. Several papers find that male-female relationships are, in the author's words, "conventional".

Vincent, A.C. 1994. "Seahorses exhibit conventional sex roles in mating competition, despite male pregnancy." Behaviour : 128-135.

As summarized in the science news Vincent finds:

sex-role reversal "had been tacitly and explicitly assumed" by researchers, she notes. Yet her lab tests in the late 1980s dashed that expectation.

When she watched various combinations of males and females sharing an aquarium tank, she found that only the males tail-wrestled. She has seen males snap their heads toward each other but hesitates to call this competition. Putting underwater microphones into tanks revealed that the fish make a noise like fingers snapping.

In competitive behaviors that males and females shared, Vincent rated the males as more intense. The male rival that triumphed in a contest for a mate typically turned out to be the heavier one. Contrary to old expectations, it looked to Vincent as if males were putting more effort into getting pregnant than females were exerting to impregnate them.

The intense male competition has raised questions about where to fit seahorses into the spectrum of animal mating systems.

More recent work confirms this conventional view of seahorse sex roles; female seahorses (species Hippocampus zosterae) have lower potential reproductive rates than males, and females are more reluctant to mate than males:

Citation: Masonjones, Heather D. and Sara M. Lewis. 2000. "Differences in potential reproductive rates of male and female seahorses in courtship roles." Animal Behaviour 59(1): 11-20. Available as a read-only pdf file at:


140 The title of this says it all: Petrie, M. 1983. "Female moorhens compete for small fat males." Science 220: 413-415.

A good non-technical article about elephant seals is: LeBoeuf, B.J. 1974. "The hectic life of the alpha bull: elephant seal as fighter and lover." Psychology Today 8:104-108; and there are some good pictures at

A more technical description of their sexual behavior and dramatic sexual dimorphism in reproductive strategies is: LeBoeuf, B.J. 1974. "Male-male competition and reproductive success in elephant seals." American Zoologist 14:163-176.

141 Maximum lifetime reproduction data are from: LeBoeuf, B.J. and Reiter. 1988. Lifetime reproductive success in northern elephant seals. In T.H. Clutton-Brock (ed.) Reproductive Success . University of Chicago Press, Chicago & London; and Clutton-Brock, T.H. 1983. "Selection in relation to sex." In D.S. Bendall (ed.) From Molecules to Men. Cambridge University Press (kittiwake gulls).
142 Data on the energetic cost of an average pregnancy come from the Food and Agriculture Organization of the United Nations ( and are discussed in detail in: Prentice, A.M. and R.G. Whitehead. 1987. "The energetics of human reproduction." Symposium of the Zoological Society of London 57:275-304.
142 In case you want to calculate how far you'd have to run or how many hamburgers you'd have to consume to equal the energetic cost of a pregnancy, see:,, and
143 Human reproductive records come from: Guinness Book of Records. 1999. Guinness Records Publishing
143 Sex differences in highway mortality come from Wilson, M. and M. Daly. 1985. "Competitiveness, risk-taking and violence: the young male syndrome." Ethology and Sociobiology 6:59-73.
144 The dramatic differences in mortality rates among male and female macaques are presented in Jolly, A. 1985. The Evolution of Primate Behavior, 2nd edition. Macmillan. See, in particular, the mortality rates on page 225 and the accompanying text: "Then, as females mature to childbearing age, their death rate falls to near zero. Subadult males, however, change troops, and fight their way into new hierarchies, or hang about on the periphery as outcasts. Their mortality peaks sharply."
145 The excellent study demonstrating a higher incidence of homosexuality among monozygotic twin brothers relative to dizygotic twin brothers is: Bailey, J.M. and R.C. Pillard. 1991. "A genetic study of male sexual orientation." Archives of General Psychiatry 48:1089-1096
145 The study of whether counseling influences whether boys with "girlish" habits eventually identify themselves as gay is described in: Greene, R. 1987. "The 'Sissy Boy Syndrome' and the Development of Homosexuality." Yale University Press.
146 An excellent source of information about homosexuality among the Sambia and an excellent ethnography in general is: Herdt, G. 1987. The Sambia. Ritual and Gender in New Guinea. Harcourt Brace Jovanovich. Page vi (foreword): "This study shows that it is entirely possible--in fact among the Sambia it is required--to move from exclusive homosexual behavior to exclusive heterosexuality. Among the Sambia, adult males are husbands, fathers, and warriors who must always be prepared for war. They do not as adults engage in homosexual practices and in fact look down upon the occasional adult male who does so, at least one who does so habitually. All of these very masculine, heterosexual males, however, have spent years engaging in homosexual acts required of them as preadult initiates, during which time they avoided women and learned to be antagonist toward them."
146 For information on the widespread occurrence of cultures in which a period of adolescent homosexuality is important, see also: Herdt, G. 1997. Same Sex, Different Cultures. Westview Publishers. For example: page 82: "The practice of boy-insemination rituals is very ancient and widespread throughout this region of the world. Approximately sixty distinct precolonial cultures practiced this form of same-gender relationship in the coastal and southwestern areas of New Guinea, some of the off-lying islands of New Hebrides, and a few of the tradition tribal groups of Australian Aborigines. this number represents approximately 10-20 percent of al the societies that have been systematically studied in this area."
146 A fascinating book on bonobo behavior is: De Waal, F. and F. Lanting. 1998. Bonobo: The Forgotten Ape. University of California Press. As a bonus, the book is filled with spectacular photographs of primates.
147 An interesting and comprehensive recent discussion of animal homosexuality is: Bagemihl, B. 1999. Biological Exuberance. Animal Homosexuality and Natural Diversity. St. Martin's Press.
147 The dramatic sex-changing ways of the blue-headed wrasse are described in: Warner, R.R. 1975. "The adaptive significance of sequential hermaphroditism in animals." American Naturalist 109:61-82.
148 The examples of "'roid rage" are from a paper presented by: Pope, H.G. and D.L. Katz. at the 1992 Annual Meeting of the American Psychiatric Association, Washington, DC. See also: Pope, H.G. and D.L. Katz. 1994. "Psychiatric and medical effects of anabolic-androgenic steroid use: A controlled study of 160 athletes." Archives of General Psychiatry 51:375-38
149 A good source of information about hyenas is:
151 Information on sex differences in the selection of medical specialties is from:
151 Data showing that more girls than boys are going to college are from:

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Beauty: It's more than skin deep
Chagnon, N. (1992). Yanomamo, 4th edition. New York, Harcourt Brace Jovanovich. See for example, pages 187 - 188: "Needless to say, the tops of most men's heads are covered with deep ugly scars of which their bearers are immensely proud. Some men, in fact, keep their heads cleanly shaved on top to display these scars, rubbing red pigment on their bare scalps to define them more precisely." See also page 188, figure 6.2: "Older men who have been in many club fights have enormous scars of which they are very proud."
153 For an example of neck stretching among the Padaungs of Southeast Asians see:
154 A classic introduction to animal behavior, including some photos of animals caught in flagrante while taking part in the mating game (for example, see plate 9.1c.) can be found in Krebs, J.R. and N. B. Davies. 1993. Introduction to Behavioral Ecology, 3rd edition.
154 More specific than Krebs and Davies but an excellent general textbook on primate behavior is: Jolly, A. 1985. The evolution of primate behavior, 2nd edition. See for example, a demonstration of just how precarious some monkey sex can be in figure 13.1, panes B and C, and figure 13.5, pane B.
155 Humans consider clear skin a sign of good health and, moreover, the greater the prevalence in a society, the more the people in that society value physical appearance in prospective mates. Gangestad, S.W. and D.M. Buss. 1993. "Pathogen prevalence and human mate preferences." Ethology and Sociobiology 14: 89-96.
155 A thorough review on the link between disease and physical appearance is: Thornhill, R. and A.P. Moller. 1997. "Developmental stability, disease and medicine." Biological Reviews of the Cambridge Philosophical Society. 72: 497-548.
155 For a detailed description of animal symmetry, its measurement and some examples of its significance, see: Palmer, A.R., and Strobeck, C. 1986. "Fluctuating asymmetry: measurement, analysis, patterns." Annual Review of Ecology and Systematics. 17:391-421.
156 Finally, a way to earn some money at the race track from our knowledge of symmetry. Just bring your digital calipers to the horse races: Manning, J.T. and L. Ockenden. 1994. "Fluctuating asymmetry in race horses." Nature. 370:185-186.
156 Humans aren't the only species that can profit by detecting symmetry in others: A.P. Moller. 1995. "Bumblebee preference for symmetrical flowers." Proceedings of the National Academy of Science. 92: 2288-2292.
156 An ingenious study illustrating the power of our subconscious attraction to symmetry is: Gangestad, S.W. and R. Thornhill. 1998. "Menstrual cycle variation in women's preferences for the scent of symmetrical men." Proceedings of the Royal Society of London, B. 265:927-933.
157 Evidence that men with symmetrical bodies have sex earlier in life and earlier in the course of a relationship is presented in: Thornhill, R. and Gangestad, S.W. 1994. "Human fluctuating asymmetry and sexual behavior." Physiological Science. 5:297-302.
157 The study linking a man's symmetry and his partners orgasmicity is: Thornhill, R., S.W. Gangestad, and R. Comer. 1995. "Human female orgasm and mate fluctuating asymmetry." Animal Behavior 50:1601-1615.
158 A nice demonstration that there is cross-cultural agreement on who is beautiful is: Cunningham, M.R., A.R. Roberts, C-H Wu, A.P. Barbee, and P.B. Druen. 1995. "'Their ideas of beauty are, on the whole, the same as ours': Consistency and variability in the cross-cultural perception of female attractiveness." Journal of Personality and Social Psychology 68:261-279.
158 The study showing that the Ache and Hiwi hunter-gatherers have similar criteria of beauty as other societies is: Jones, D. and K. Hill. 1993. "Criteria of facial attractiveness in five populations." Human Nature 4:271-295.
159 For evidence that babies stare longer at pictures of attractive people than of unattractive people, see: Langlois, J.H., L.A. Roggman, and L.A. Reiser-Danner. 1990. "Infants' differential social responses to attractive and unattractive faces." Developmental Psychology 26:153-159.
161 An excellent summary of available data on variation within and between populations as well as the significance of those data is: Molnar, S. 1988. Human Variation: Races, Types, and Ethnic Groups. Prentice Hall. In particular, see page 119 for a table comparing HLA haplotypes among 13 different populations.
161 A wealth of data on just how many sperm and eggs men and women are producing is contained within: Bellis, M.A. and R.R. Baker. 1995. Human Sperm Competition: Copulation, Masturbation and Infidelity. Chapman and Hall.
162 The vital stats on Miss Americas are summarized in: A. Mazur. 1986. "U.S. trends in feminine beauty and over adaptation." Journal of Sex Research 22:281-303.
162 For an interesting discussion of waist-to-hip ratios, see: D. Singh. 1993. "Adaptive significance of waist-to-hip ratio and female physical attractiveness." Journal of Personality and Social Psychology 65:293-307.
163 Artificial insemination success as a function of waist-to-hip ratio is presented in: B.M. Zaadstra, J.C. Seidell, P.A.H. Van Noord, E.R. te Velde, J.D.F. Habbema, B. Vrieswijk, and J. Karbaat. 1993. "Fat and female fecundity: prospective study of effect of fat distribution on conception rates." British Medical Journal 306:484-487.
163 Many studies document sex differences in the preferred age of mates, including: Hill, R. 1945. Campus values in mateselection. Journal of Home Economics 37:554-558; McGinnis, R. 1958. Campus values in mate selection. Social Forces 35:368-373; and, more recently, Buss, D. 1989. Sex differences in human mate preferences: Evolutionary hypotheses testing in 37 cultures. Behavioral and Brain Sciences 12:1-49.
163 For a nice little compendium of Barbie facts, see:
163 Attractiveness among composite photos of faces is discussed in: Langlois, J.H. and L.A. Roggman. 1990. "Attractive faces are only average." Psychological Science 1:115-121; and Grammar, K. and Thornhill, R. 1994. "Human (Homo sapiens) facial attractiveness and sexual selection: The role of symmetry and averageness." Journal of Comparative Psychology 108:233-242.
163 Facial features that contribute most to making a face beautiful are described in: Perrett, D.I., K.A. May, and S. Yoshikawa. 1994. "Facial shape and judgements of female attractiveness." Nature 368:239-242.
164 "Sex bombs" and their irresistibility are described in: Dawkins, R. 1995. River out of Eden: A Darwinian View of Life. Basic Books. See page 63.
165 Personal ads reveal interesting things about what some people are looking for in mates: Deaux, K. and R. Hanna. 1984. "Courtship in the personals column: The influence of gender and sexual orientation." Sex Roles 11:363-375; and Hatala, M.N. and J. Prehodka, 1996. "Content analysis of gay male and lesbian personal advertisements." Psychological Reports 78:371-374.
165 The effect of a woman's pupil size on a man's willingness to volunteer to be her partner in a psychology experiment is described in: Stass, W. and F.N. Willis, Jr. 1967. "Eye contact, pupil dilation, and personal preference." Psychonomic Science 7:375-376.
166 Data showing that attractive women have a hard time making and keeping friends are found in: Krebs, D. and A.A. Adinolfi. 1975. "Physical attractiveness, social relations and personality style." Journal of Personality and Social Psychology 31:245-253.
167 The Burger King uniform vs. Rolex watch study and discussion of its significance are described in: Townsend, J.M. and G.D. Levy. 1990. "Effect of potential partners' physical attractiveness and socioeconomic status on sexuality and partner selection." Archives of Sexual Behavior 19:149-164; and Townsend, J.M. and G.D. Levy. 1990. "Effect of potential partners" costume and physical attractiveness on sexuality and partner selection." Journal of Psychology 124:371-389. See also
168 Very interesting data on the characteristics preferred by males and by females (and, in particular, that women and men differed consistently across all 37 cultures in that women prefer older partners on average, and men prefer younger partners on average) are given in a table by D. Buss on page 420 in: Crawford, C. and D.L. Krebs. 1997. Handbook of Evolutionary Psychology : Ideas, Issues, and Applications. Lawrence Erlbaum Associates.
169 The data on height and salary come from: Frieze, I.H., J.E. Olson, and D.C. Good. 1990. "Perceived and actual discrimination in the salaries of male and female managers," Journal of Applied Social Psychology 20:46-47.
169 The fact that we generally vote for tall men for president is discussed in: McGinnis, J. 1976. The Selling of the President. Andre Deutsch.
169 Most of us do lie about our height and the proof can be found in: Dillon, D.J. 1962. "Measurement of perceived body size." Perceptual and Motor Skills 14:191-196.
169 Evidence that teachers treat students differently based on their attractiveness is presented in: Clifford, M.M. and E. Walster. 1973. "Research note: The effects of physical attractiveness on teacher expectations, " Sociology of Education 46:248-258; and Clifford, M.M. 1975. "Physical attractiveness and academic performance, " Child Study Journal 4:201-209.
170 The dime in the phone booth study is from: Sroufe, R., A. Chaiken, R. Cook and V. Freeman. 1977. "The effects of physical attractiveness on honesty: A socially desirable response." Personality and Social Psychology Bulletin 3:59-62.
171 Again, data on the characteristics preferred by males and by females across many cultures are summarized by D. Buss on page 420 in: Crawford, C. and D.L. Krebs. 1997. Handbook of Evolutionary Psychology : Ideas, Issues, and Applications. Lawrence Erlbaum Associates.
171 Interesting data and discussion on the traits women want in their sperm donors are given in: Scheib, J.E., A. Kristiansen, and A. Wara. 1997. "A Norwegian Note on 'Sperm Donor Selection and the Psychology of Female Mate Choice.'" Evolution and Human Behavior 18:143-150.

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Infidelity: Our cheating hearts
The torturing of experimental subjects by having them imagine misbehaving partners is reported in: Buss, D.M., R. Larsen, D. Westen, and J. Semmelroth. 1992. "Sex differences in jealousy: evolution, physiology, and psychology." Psychological Science 3:251-255.
174 Data on the proportion of Americans admitting to marital infidelities are presented in: Hunt, M.M. 1974. Sexual Behavior in the 1970s. Playboy Press; These data were confirmed in the Redbook study detailed in: Tavris, C. and S. Sadd. 1977. The Redbook Report of Female Sexuality. Delacorte Press.
174 Numerous studies making estimates of cuckoldry rates among humans are summarized in: Baker, R. and M. A. Bellis 1995. Human Sperm Competition. Copulation, Masturbation, and Infidelity. Chapman and Hall. Perhaps the best study is: Sasse, G., H. Muller, R. Chakraborty, and J. Ott. 1994. "Estimating the frequency of nonpaternity in Switzerland." Human Heredity 44:337-343. This is the very careful and conservative study, in which they tested 1,607 children and found 11 cases of misidentified paternity.

The British study of cuckoldry was reported widely in the media (see, for instance, the Sunday London Times excerpt below.) It should be noted that these data come from individuals that came to a laboratory that does paternity testing and, consequently, must be assumed to have more reason than average to suspect cuckoldry.

The Times (Britain)
23 January 2000

At least one in 10 children was not sired by the man who believes he is their father, according to scientists in paternity testing laboratories.

Some laboratories have reported the level of "unexpected" paternity to be as high as one in seven when they perform DNA genetic tests on blood samples from supposed parent and offspring. There are now seven government-approved laboratories doing paternity testing. Cellmark Diagnostics in Abingdon is the largest and receives more than 10,000 requests a year. One in five of them is "private" and has not been ordered as a result of a court or Child Support Agency dispute.

David Hartshorne, spokesman for Cellmark, said that in about one case in seven, the presumed father turns out to be the wrong man. "It is surprising how often the mother is wrong about the person she thinks is the father," he said. Marriage breakdown and more births outside marriage have increased disputes about paternity and the desire for testing, he added.

In addition to DNA evidence, other studies of mass blood samples suggest that increasing numbers of women are unsure if their husbands are the fathers of their children. This phenomenon of misattributed fatherhood has been investigated in a newly published study by social scientists at the London School of Economics (LSE). Oliver Curry, the principal researcher, said long working hours and commuting by fathers could contribute to uncertainty about whether children have been fathered by the man who is bringing them up.

"It can have major consequences for the way men treat their supposed children and the amount of time, money and emotion they invest in them," Curry said. "It can range through the entire spectrum from serious abuse to deciding not to pay for their education, or not buying them the latest expensive trainers."

The team from the LSE is calling for investigations to be set up by the government's new National Family and Parenting Institute. They believe that mistrust over paternity may be an overlooked factor in family breakdown. Women are driven by primitive urges to seek the optimum genes for their children, which can lead to them sleeping with a "high social-status Casanova" as well as their regular partner during the fertile period around ovulation, researchers claim.

David Buss, a psychologist from the University of Texas who is about to publish a new study on the subject, said: "A proportion of these misattributed fathers will believe that the child is genuinely theirs, and often the mother tries to foster that belief." He also estimates that the tendency for women to shop around for the best genes leads to them making mistakes about who has fathered their child.

Soraya Khashoggi, 57, former wife of arms dealer Adnan Khashoggi, has revealed how DNA tests established her 18-year-old daughter, Petrina, to be the child of Jonathan Aitken, the disgraced former Conservative minister. Khashoggi said her ex-husband had completely accepted Petrina: "He gave her his name without ever asking who her true father was," she said.

Paula Yates, the television personality, discovered at 37 that her real father was Hughie Green, the Opportunity Knocks star.


174 Dan Quayle's comments were in a speech on the causes of the LA riots. He said: "Bearing babies irresponsibly is wrong. Failing to support children one has fathered is wrong. It doesn't help matters when prime time TV has Murphy Brown—a character who supposedly epitomizes today's intelligent, highly paid, professional woman—mocking the importance of fathers by bearing a child alone and then calling it just another 'lifestyle choice.'"
175 The red-winged blackbird vasectomy data are from: Bray, O.E., J.J. Kennelly, and J.L. Guarino. 1975. "Fertility of eggs produced on territories of vasectomized red-winged blackbirds." Wilson Bulletin 87:187-195.
175 Testicle measurements are reported in: Smith, R.L. 1984. Sperm Competition and the Evolution of Mating Systems. Academic Press (see pages 601-659); and Short, R.V. 1979. "Sexual selection and its component parts, somatic and genital selection, as illustrated by man and great apes." Advances in the Study of Behavior 9:131-158.
176 Numerous researchers have recounted the prodigious displays of chimp sexual activity. Jane Goodall, notes, for example: "Tutin, analyzing the rate at which females copulated during the day, found that there was an average of between five and six copulation per female per hour in the early morning, after which the rate dropped gradually to about two per hour in the midmorning, rose very slightly during the afternoon, and tapered off to one per hour in the evening." This and additional accounts are presented in the classic: Goodall, J. 1986. The Chimpanzees of Gombe: Patterns of Behavior. Harvard University Press.
176 In their guide to testicular cancer, the National Cancer Institute reports that: Many men worry that losing one testicle will affect their ability to have sexual intercourse or make then sterile. But a man with one healthy testicle can still have a normal erection and produce sperm. Therefore, an operation to remove just one testicle does not make a patient impotent and seldom interferes with fertility. For more information, see:
177 Data on the relative proportion of "seek-and-destroy" sperm, blockers and "egg-getter" sperm as a function of time that a couple have spent apart are from: Bellis, M.A. and R.R. Baker. 1995. Human Sperm Competition: Copulation, Masturbation and Infidelity. Chapman and Hall. They also report here that males respond to increased risk that the female has had sex with another male (with the risk assessed as a function of the percent time they've spent together since their last copulation) by increasing the number of sperm inseminated. When couples are together for 100% of this time, there are an average of 389 million sperm per ejaculate. When they are together for only 5% of the time, the number of sperm per ejaculate nearly doubles, to 712 million.
177 For a few examples of the harsh social sanctions and disincentives that are sometimes used to restrict adultery, see:, and Guglielmo, V. 1999. "Human rights and refugees: the case of Kenya." Journal of Refugee Studies 12:63.
178 Divorce rates are lower among couples with more children. The raw data are from: United Nations Statistical Office, Demographic Yearbook. United Nations. They found that 39% of divorces occur when there are no children, 26% when there is a single child, 19% when there are two, and less than 3% when there are four or more.
178 There is a huge literature cataloging and dissecting the reasons why couples break up. An excellent and accessible general book that reviews the seminal studies is: Fisher, H.E. 1992. Anatomy of Love. Norton. An interesting original account of one society is: Radcliffe-Brown, A.R. 1922. The Andaman Islanders. Cambridge University Press.
178 The no-fault divorce system of ring doves is described in: Erickson, C.J. and P.G. Zenone. 1976. "Courtship differences in male ring doves: Avoidance of cuckoldry?" Science 192:1353-1354.
179 The 160 culture study of why couples break up (describing 43 different causes of divorce and highlighting infidelity and infertility at the top of the list) is described in: Betzig, L. 1989. "Causes of conjugal dissolution: A cross-cultural study." Current Anthropology 30:654-676.
179 Data on when divorce is most likely to occur—i.e. the "four-year itch"—are from: Fisher, H.E. 1989. "Evolution of human serial pairbonding." American Journal of Physical Anthropology. 78:331-354; and Fisher, H.E. 1991. "Monogamy, adultery and divorce in cross-species perspective." In Man and Beast Revisited, (M.H. Robinson and L. Tiger, eds.). Smithsonian Institution Press. (But see also her Anatomy of Love cited above.)
179 Remarriage rates are from: Cherlin, A.J. 1981. Marriage, Divorce, Remarriage. Harvard University Press.
179 Our desire to marry has not decreased as divorce rates have increased. Cherlin (from the reference above) documented that more than 90% of Americans marry. Moreover, data collected by the United Nations on 97 societies, indicates that between the years 1972 and 1981, an average of 93.1% of women and 91.8% of men married by age 49. This is reported in: Fisher, H.E. 1989. "Evolution of human serial pairbonding." American Journal of Physical Anthropology 78:331-354.
180 The relationship between womenâs earning power and divorce rates is discussed in Cherlin, A.J. 1981. Marriage, Divorce, Remarriage. Harvard University Press; and Fisher, H.E. 1992. Anatomy of Love. The specific case of the Navajo is described in: Van den Berghe, P.L. 1979. Human Family Systems: An Evolutionary View. Greenwood Press.
180 Fifty-six percent of men who have extramarital sex describe their marriages as "happy" while only 33% of women do. See: Glass, D.P. and T.L. Wright. 1985. "Sex differences in type of extramarital involvement and marital dissatisfaction." Sex Roles 12:1101-1120.
180 Data on the increase of extramarital sex with increasing age among men are from: Kinsey, A.C., W.B. Pomeroy, and C.E. Martin. Sexual Behavior in the Human Male. 1948; and Kinsey, A.C., W.B. Pomeroy, and C.E. Martin. Sexual Behavior in the Human Female. 1953; See also Wiederman, M.W. 1997. "Extramarital sex: Prevalence and correlates in a national survey." The Journal of Sex Research 34:167-174.
181 For more of the details on Hal and Miriamâs hangingly mating ritual, see: Thornhill, R. 1976. "Sexual selection and nuptial feeding behavior in Bittacus apicalis (Insecta: Mecoptera)." American Naturalist 110:529-548.
182 The hummingbird exchange of access to food for mating opportunities is described in: Wolf, L.L. 1975. "Prostitution behavior in a tropical hummingbird." Condor 77:140-144.
184 For excellent evidence that, in nature, offspring don't always come from the apparent father, see Birkhead, T.R., J.E. Pellatt, and F.M. Hunter. 1988. "Extra-pair copulation and sperm competition in the zebra finch." Nature 334:60-62; and Birkhead, T.R., T. Burke, R. Zann, F.M. Hunter, and A.P. Krupa. 1990. "Extra-pair paternity and intra-specific brood parasitism in wild zebra finches, Taeniopygia guttata, revealed by DNA fingerprinting." Behavioral Ecology and Sociobiology 27:315-324.
184 Data demonstrating that female matings outside of their pair bond are predominantly with males more attractive than their mate are from: Houtman, A.M. 1992. "Female zebra finches choose attractive partners for extra-pair copulations." Proceedings of the Royal Academy of Sciences, London B 249:3-6.
185 At what time of the month are women having affairs? A study of 3679 women in Britain found that copulations outside of marriage occurred more frequently at the point in their ovulatory cycle when they are most fertile. The data are reported in: Baker, R. and M. A. Bellis 1995. Human Sperm Competition. Copulation, Masturbation, and Infidelity. Chapman and Hall. (See page 197).
185 For data and discussion of the extent to which marital satisfaction is low among women having affairs, se: Greiling, H. and D.M. Buss. 2000. "Women's sexual strategies: the hidden dimension of EPM." Personality and Individual Differences 28:929-963; See also Glass, S.P. and T.L. Wright. 1992. "Justifications for extramarital relationships: the association between attitudes, behaviors and gender." Journal of Sex Research 29:361-387, where they found that 77% of women were looking for love and emotional intimacy in an affair.
185 Paternal resemblance was alleged far more often than maternal resemblance in a videotape study of 111 individuals by: Daly, M. and M. Wilson. 1982. "Whom are newborn babies said to resemble?" Ethology and Sociobiology 3:69-78.
186 Infanticide by males towards the babies of other males is reported in: Cassini, M.H. 1998. "Inter-specific infanticide in South American otariids." Behavior 135:1005-1012; and Borries, C., K. Launhardt, C. Epplen, J.T. Epplen, and P. Winkler. 1999. "Males as infant protectors in Hanuman langurs (Presbytis entellus) living in multimale groups - defence pattern, paternity and sexual behaviour" Behavioral Ecology and Sociobiology 46:350-356. In this latter study, of 22 attacks on infant langurs by males, only the genetic father (or a male who was present when infant was conceived) would protect infants.
186 The Nicole and Michelle lemming infanticide story is described in Mallory, F.F. and R. Brooks. 1978. "Infanticide and other reproductive strategies in the collared lemming, Dicrostoyx groenlandicus." Nature 273:144-146.
187 Troop dynamics among the langur monkeys of India and the female strategy of confusing paternity are described in the classic book: Hrdy, S.B. 1981. The Woman that Never Evolved. See also Hrdy, S.B. 1999. Mother Nature : A History of Mothers, Infants, and Natural Selection. Pantheon Books.
188 The "partible paternity" insurance policy among the Ache is described in: Hill, K. and M. Hurtado 1996. Ache Life History: The Ecology and Demography of a Foraging People. Aline De Gruyter. (See page 444.)
189 Homicide statistics are from the Federal Bureau of Investigation:
189 Mate guarding methods and some examples are described in: Krebs, J.R. and N.B. Davies. 1993. An Introduction to Behavioral Ecology, 3rd edition. Blackwell Scientific Publications. See page 184 for a good description of post-copulatory guarding in damselflies.
191 For an example of male mate guarding that occurs only during the female fertile period, see: Saino, N., C.R. Primmer, H. Ellegren, and A.P. Moller. 1999. "Breeding synchrony and paternity in the barn swallow." Behavioral Ecology and Sociobiology 45:211-218.
192 The cement-gland wielding parasites of the Phylum Acanthocephala are described at; An account of their homosexual use of this gland is given in: Abele, L. and S. Gilchrist. 1977. "Homosexual rape and sexual selection in acanthocephalan worms." Science 197:81-83.
193 Male injection of sperm into other males for use in later fertilizations is described in: Carayon, J. 1974. "Insemination traumatique heterosexuelle et homosexuelle chez Xylocoris maculipennis (Hem. Anthocoridae)." C.R. Academy of Sciences, Paris D 278:2803-2806.
193 The damselfly shovel-penis is described in more detail than you would probably like in: Cordero, A., S. Santolamazza, & C. Utzeri. 1995. "Male disturbance, repeated insemination, and sperm competition in the damselfly, Coenagrion scitulum (Zygoptera: Coenagrionidae)." Animal Behavior 49:437-449.
193 Sea water squirting as a method of sperm competition among sharks is described in: Lineaweaver, T.H. and R.H. Backus. 1970. The Natural History of Sharks. J.P. Lippincott Compny.
193 The toxic semen of fruitflies is described in Wolfner, M.F. 1997. "Tokens of love: functions and regulation of Drosophila male accessory gland products." Insect Biochemistry and Molecular Biology 27:179-192.

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Family: The ties that bind
For a discussion of features of all human societies including the centrality of genetic relatedness see, Brown, Donald E. 1991. Human Universals. Temple University Press.

For !Kung San norms with respect to conversation see, Lee, Richard. 1993, 2nd ed. The Dobe Ju/'hoansi. Harcourt Brace.

"A person's behavior is very different toward joking kin compared with avoidance kin. With a joking relative one acts in a relaxed fashion and speaks on familiar terms... The most heavily weighted avoidance relations occur between a man and his mother-in-law and between a woman and her father-in-law. Here even direct speech is not to occur. (In practice it frequently does, however.)" --p 70.


Yanomamö marriage and suaböya are discussed in, Chagnon, Napoleon. 1992. Yanomamo, 4th edition. Harcourt Brace Jovanovich.

"Men marry women they call suaböya. Their kinship system literally defines who is and who is not marriageable, and there are no terms for what we would call 'in-laws'. In a word, everyone in Yanomamo society is called by some kinship term that can be translated into what we would call blood kin." p 139.

201 A chatty description of the Australian Social Spider's mothering habits can be found online: Liquid moms
202 Polyganous tasmanian hens, Maynard Smith, J. and M.G. Ridpath. 1972. "Wife sharing in the Tasmanian native hen Tribonyx mortierii: a case of kin selection?" American Naturalist 106: 447-52.
202 The seminal papers on the shared genes as a basis for altruism are, Hamilton, W.D. 1964. "The Genetical Evolution of Social Behavior I and II." Journal of Theoretical Biology 7: 1-16, 17-52.
203 For a discussion of human polyandry see, Crook, J.H. and S.J. Crook. 1988. Tibetan Polyandry: Problems of Adaptation and Fitness. in L. Betzig, M. Borgerhoff Mulder and P. Turke, eds., Human Reproductive Behaviour: A Darwinian Perspective: Cambridge University Press 97-114.
203 The seminal paper on ground squirrels is, Sherman, Paul W. 1977. "Nepotism and the Evolution of Alarm Calls." Science 197: 1246-53.
204 Bulky bouncer bees give preference to their genetic relatives, Greenberg, I. 1979. "Genetic component of kin recognition in primitively social bees." Science 206: 1095-7.
205 Tadpoles swim with their genetic relatives, Waldman, Bruce. 1985. "Olfactory basis of kin recognition in tadpoles." Journal of comparative physiology 156: 565-577.
205 Crime within the family. U.S statistics on violence within the family from the F.B.I. It says, "of the 214,464 victims of violent offenses, 57,985 or 27 percent, were reported to have been related to one or more of the offenders."
205 The role of genes in violence is discussed in, Daly, Martin and Margo Wilson. 1988. Homicide. Aline de Gruyter.
206 Spousal Murder rates from the U.S. Department of Justice. November 1994, NCJ 149259, it says, In 1977, 54% of the murder victims who were killed by intimates were female. By 1992, the ratio of female to male victims had changed, with 70% of the victims being female. The number of male victims fell from 1,185 in 1977 to 657 in 1992 and the number of female victims increased from 1,396 to 1,510 during the same period.
206 Yanomamö villages divide along genetic lines, Chagnon, Napoleon. 1992. Yanomamo, 4th edition. Harcourt Brace Jovanovich. P 143.
206 The data on stepparents come from, Daly, Martin and Margo Wilson. 1998. The Truth about Cinderella. A Darwinian View of Parental Love. They write, "the estimated rates of step-parent-plus genetic parent households had grown to approximately one hundred times greater than in two-genetic-parent households." --p 28.
207 Plato on private property in the ideal state. The Republic 416e.
207 U.S. Crime statistics from the F.B.I.
208 Bees, mud daubers, family values and stinging are discussed in, Wilson, Edward Osborne. 1978. On Human Nature. Harvard University Press. p 151

The mother-fetus battle over nutrient flow is discussed in, Haig, David. 1993. "Genetic Conflicts in Human Preganancy." The Quarterly Review of Biology, 68(4): 495-532. It says,

"hPL is proposed to act on maternal prolactin receptors to increase maternal resistance to [her own] insulin. If unopposed, the effect of hPL would be to maintain higher blood glucose levels for longer periods after meals. This action, however, is countered by increased maternal production of insulin. Gestational diabetes develops if the mother is unable to mount an adequate response to fetal manipulation." --p 495

211 Mothers attitudes towards babies and the conditions that foster infanticide are discussed in, Hrdy, Sarah Blaffer. 1999. Mother Nature: A History of Mothers, Infants, and Natural Selection. Pantheon Books.
211 George Washington's Farewell Speech online

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Friends and Foes: Keep friends close and enemies closer

Chimpanzee intergroup aggression is described in, Goodall, Jane. 1986. The Chimpanzees of Gombe: Patterns of Behavior. Belknap Press of Harvard University Press. See in particular the discussion on pp 488-534.

"In the chimpanzee, territoriality functions not only to repel intruders from the home range, but sometimes to injure or eliminate them; not only to defend the existing home range and its resources, but to enlarge it opportunistically at the expense of weaker neighbors; not only to protect the female resources of a community, but to actively and aggressively recruit new sexual partners from neighboring social groups." -- p 528


Chimpanzee aggression and its implications for human society are explored in, Wrangham, Richard and Dale Peterson. 1996. Demonic Males. Houghton Mifflin.

"Defense of territory is widespread among many species, but the Kasekela chimpanzees were doing more than defending. They didn't wait to be alerted to the presence of intruders. Sometimes they moved right through border zones and penetrated half a mile or more into neighboring land. They did no feeding on these ventures. And three times I saw them attack lone neighbors. So they seemed to be looking for encounters in the neighboring range. These expeditions were different from mere defense, or even border patrols. These were raids." --p 13


The peaceful and aggressive Polynesian societies are described in, Diamond, Jared. 1998. Guns, Germs and Steel: The Fates of Human Societies. pp 53 -- 57.

"The Moriori were a small, isolated population of hunter gatherers, equipped with only the simplest technology and weapons, entirely inexperienced at war and lacking strong leadership and organization. The Maori invaders (from New Zealand's North Island) came from a dense population of farmers chronically engaged in ferocious wars, equipped with more-advanced technology and weapons, and operating under strong leadership." --p 54

215 Experiments on co-operation and group identity are described in, Bornstein, Gary and Meyrav Ben-Yossef. 1994. "Cooperation in intergroup and single-group social dilemmas." Journal of Experimental Social Psychology, 1 30: 52-67, and McCallum, Debra M. and et al. 1985. "Competition and cooperation between groups and between individuals." Journal of Experimental Social Psychology, 21(4): 301-320.
216 Human male testosterone levels rise before physical competitions in several settings including tennis and wrestling as described in, Elias, M. 1981. "Serum cortisol, testosterone, and testosterone-binding globulin responses to competitive fighting in human males." Aggressive Behavior 7: 215-224, and Booth, Alan, Greg Shelley, Allan Mazur and Gerry Tharp. 1989. "Testosterone, and winning and losing in human competition." Hormones & Behavior 23(4): 556-571.
216 Human testosterone levels in non-physical competitions show a similar pattern to that of tennis and wrestling as shown in, Mazur, Allan, Alan Booth and James M. Dabbs. 1992. "Testosterone and chess competition." Social Psychology Quarterly, March 55(1): 70-77, and McCaul, Kevin D., Brian A. Gladue and Margaret Joppa. 1992. "Winning, losing, mood, and testosterone." Hormones & Behavior 26(4): 486-504.
216 A study showing that fans have testosterone reactions similar to combatants is, Bernhardt, Paul C. , James M. Jr. Dabbs, Julie A. Fielden and Candice D. Lutter. 1998. "Testosterone changes during vicarious experiences of winning and losing among fans at sporting events." Physiology & Behavior, Aug. 65(1): 59-62.
216 Philadephia victory celebration, "From the moment the parade kicked off at 18th and Kennedy Boulevard to the moment it ended 90 minutes later at John F. Kennedy Stadium, there was non-stop cheering, chanting and screaming from a crowd estimated at more than a half-million." Philadelphia Daily News, October 23, 1980.

A good review article on the effects of race on reaction time is, Banaji, Mahzarin R. and Nilanjana Dasgupta. 1998. The Consciousness of Social Beliefs: A Program of Research on Stereotyping and Prejudice. in Vincent Y. Yzerbyt, Guy Lories and Benoit Dardenne, eds., Metacognition: Cognitive and social dimensions: Sage Publications 157-170.

Professor Mahzarin R. Banaji is a leader in this research; you can visit her webpage and you can also take test yourself online for unconsicious biases using the tasks ("IAT" - Implicit Association Test) used in this research. Take an IAT online

219 A good summary of race and genetic differences is contained in, Marks, Jonathan. 1995. Human Biodiversity. Genes, Race, and History.
221 That modern Africans have genes that represent 93% of all human genetic diversity is from, Lewontin, Richard C. 1982. Human Diversity. Freeman and Co. p 123.
221 A recent article using DNA techniques to determine the evolutionary history of apes is, Ruvolo, Mary E. 1997. "Genetic Diversity in Hominoid Primates.": Annual Review of Anthropology 26: 515-540.
222 World War I battle (and peace) description is covered in, Axelrod, Robert. 1984. The Evolution of Cooperation. Basic Books.
224 Vampire bat blood sharing is described in, Wilkinson, G.S. 1984. "Reciprocal food sharing in the vampire bat." Nature 308: 181-4.
224 A beautiful article on orangutans, which includes a discussion of their generally solitary lives, is, Knott, Cheryl. 1998. "Orangutans in the Wild." National Geographic, August 194(2): 30-57.
225 The seminal paper on the selfish nature of altruism towards non-kin is, Trivers, Robert L. 1971. "The Evolution of Reciprocal Altruism." Quarterly Review of Biology 46(4): 35-57.
226 Hermaphroditic Black Hamlet fish mating described in, Fischer, E.A. 1980. "The relationship between mating system and simultaneous hermaphroditism in the coral reef fish, Hypoplectrus nigricans." Animal Behavior 28: 620-33.
227 The seminal ultimatum game study is, Guth, Werner, Rolf Schmittberger and Bernd Schwarze. 1982. "An Experimental Analysis of Ultimatum Bargaining." Journal of Economic Behavior and Organization, December 3(4): 367-388. The origin finding of "fairness" has been verified even when the pot is large. See, for example, Cameron, Lisa. 1999. "Raising the stakes in the ultimatum game: experimental evidence from Indonesia." Economic Inquiry 37(1): 47-59.
229 For a discussion of when mates desert see, Lazarus, J. 1990. "The logic of mate desertion." Animal Behavior 39: 672-684. Eens, M. and R. Pinxten. 1995. "Mate desertion by primary female European starlings at the end of the nestling stage." Journal of Avian Biology 26: 267-271.
230 A good account of chimpanzee's continual testing of strength is, Goodall, Jane. 1986. The Chimpanzees of Gombe: Patterns of Behavior. Belknap Press of Harvard University Press. --p 324
231 Prosopagnosia and brain discussed in, Damasio, A. D., H. Damasio and G. W. Van Hoesen. 1982. "Prosopagnosia: Anatomic basis and behavioral mechanisms." Neurology 32: 331-342.
232 Vervet monkey grooming and alliance formation, Seyfarth, R.M. and DL Cheney. 1984. "Grooming, alliances and reciprocal altruism in vervet monkeys." Nature 308: 541-3.
232 The Kula Ring is described in, Malinowski, Bronislaw. 1922. Argonauts of the Western Pacific. E.P. Dutton. See Chapter III, "The Essential of the Kula."
233 The idea of gossip as an evolutionary adaptation, and its exploitation by soap operas and tabloids is advanced in, Barkow, Jerome H. 1992. Beneath New Culture is Old Psychology: Gossip and Social Stratification. in Jerome H. Barkow, Leda Cosmides and John Tooby, eds., The Adapted Mind: Evolutionary Psychology and the Generation of Culture. New York: Oxford University Press 627-638.
235 The universally selfish and obligatory nature of gifts is noted in, Mauss, Marcel. 1954. The Gift; forms and functions of exchange in archaic societies. Free Press.
236 Adam Smith quote is from The Wealth of Nations, vol. 1, bk. 1, ch. 2 (1776).
237 The laboratory study of corporate gifts and the effects on workers is, Fehr, Ernst, Erich Kirchler, Andreas Weichbold and Simon Gachter. 1998. "When Social Norms Overpower Competition: Gift Exchange in Experimental Labor Markets." Journal of Labor Economics, April 16(2): 324-51.
237 The photocopier study is reported in, Langer, Ellen J. 1978. Rethinking the Role of Thought in Social Interaction. in John Harvey, William J. Ickes and Robert Kidd, eds., New Directions in Attribution Research. New York: L. Erlbaum Associates 48-9.
238 The naughty and nice seminarians study is Darley, J.M. and C.D. Batson. 1973. "From Jerusalem to Jericho: A study of situational and dispositional variables in helping behavior." Journal of Personality and Social Psychology 27(1): 100-108.
240 U.S. voting figures from the Federal Election Commission,
241 Some interesting reporting on Nelson Mandela's prison time can be found online at
241 Figures for deaths and injuries from arguments with strangers in, Cohen, Dov, Richard E. Nisbett, Brian F. Bowdle and Norbert Schwarz. 1996. "Insult, Aggression, and the Southern Culture of Honor: An 'Experimental Ethnography'." Journal of Personality & Social Psychology, 5 70: 945-960.
242 Full Metal Jacket screenplay online

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Conclusion: Surviving Desire

Herring gull nesting behavior and egg retreival are discussed in, Baerends, G. P. and R. H. Drent. 1982. The herring gull and its egg. Part I. Behaviour, Suppl. 17: 1-312. Baerends, G. P. and R. H. Drent. 1982. The herring gull and its egg. Part II. Behaviour 82: 1-415. and Baerends, G.P. and J. P. Krujit. 1973. Stimulus selection. in R.A. Hinde and J Stevenson-Hinde, eds., Constraints on Learning. New York: Academic Press 23-50.

For a nice summary of the different types of fake eggs used and herring gull preferences, see:

See also Obituary of herring gull expert, Gerard Baerends

Baerends & Kruijt (1973) found that herring gulls:

· prefer the larger of two eggs of the same colour

· prefer the speckled egg over an unspeckled egg of the same colour

prefer natural coloured (brown speckled) eggs over brown unspeckled eggs

prefer green speckled eggs over green unspeckled eggs

· prefer green eggs over brown eggs.

An important finding of theirs is that the preference for larger eggs remains the same when other features like shape and colour are changed. This means that each feature (colour and speckling) adds a specific contribution that is independent of the contribution of the other features. In other words the features are additive in their effect on the gulls' behaviour.


The story of one group of the !Kung San and their boreholes is told in, Tanaka, J. 1987. The Recent Changes in the Life and Society of the Central Kalahari San. in African Study Monographs 37-51.

In 1962, under George Silberbauer, 5 test holes were bored in a 50 x 50km area. They were improved in 1979, leading to a stable water supply.

"…stable water supply from boreholes was the greatest factor to attract people. … Thus a great number of people came around !Koi!kom borehole. As a result, an extraordinarily large settlement suddenly sprang up. … The number increased to 520 at the end of 1982 owing to the severe drought and free food distribution by the government. … Wild plants which they relied [on for] 80% of their food disappeared rapidly, and the people of Kade were forced to depend on aid food. … Shortage of wood around !Koi!kom has become serious year after year, and now they are forced to go out as far as 3km to collect wood. Besides firewood, they need materials to build fences to protect their gardens from animals and to build their own huts. Thus the trees near the settlement have been completely cut down, and desertification is rapid in progress. … If the sedentary life continues, a large-scale destruction of nature will be inevitable."


Sugar content of natural and manufactured foods was observed in, Kugel, Allan. 1999. Evolution and the Utility Self-Subversion Effect. Manuscript. Kugel's manuscript online.

The key diagram is on page 7 in this paper. It it, sugar content is listed by percent weight.

Bananas can be seen as the highest of the natural foods listed, with about 14% sugar content by weight (reading from a graph).

Oranges are just under 10%.

Among manufactured foods listed we have granola cereal at 30%, Sugar Smacks cereal at over 55%, candy "(typical)" also at over 50% and jam-filled sponge cake at 50%.

One caveat to these numbers: the lower water content of the manufactured products listed may be exaggerating the differences

The reference for the sugar content is: Home Economics Research Report No. 48, Sugar Content of Selected Foods: Individual and Total. U.S.D.A., 1987:



A 16 oz. box of Cap'n Crunch contains almost 7 ounces of sugar.

Product Information: Quaker Captain Crunch Cereal Size: 16 oz. box.

Nutrition Facts

Servings Per Container: 17

Amount Per Serving Calories 150

Total Carbohydrate 23.0 g, Sugars 12.0 g

In the whole box we have 17 servings * 12 grams/serving = 204 grams of sugar * 1 oz/ 28.35 grams = 45.0% sugar


Gordon Gekko's speech in Oliver Stone's movie Wall Street -

"Greed, for lack of a better word, is good. Greed is right. Greed works. Greed clarifies, cuts through and captures the essence of the evolutionary spirit. Greed in all its forms, greed for life, greed for money, for love, knowledge, has marked the upward surge of mankind and greed, you mark my words, will not only save Teldar paper, but that other malfunctioning corporation called the U.S.A."


Walter Mischel conducted dozens of experiments on deferral of gratification including the marshmallow studies. A nice review of this work is, Mischel, Walter, Yuichi Shoda and Monica Rodriguez. 1989. "Delay of Gratification in Children." Science, 244: 933-938. Professor Mischel's web site

Mischel et al. report: "After children understand the contingency, they are left on their own during the delay period while their behavior is observed unobtrusively, and the duration of their delay is recorded until they terminate or the experimenter returns (typically after 15 minutes).

They also state that: "A recent follow-up study of a sample of these children found that those who had waited longer in this situation at 4 years of age were described more than 10 years later by their parents as adolescents who were more academically and socially comptent than their peers and more able to copy with frustration and resist tempation."

And finally: "seconds of delay time in preschool also were significantly related to their Scholastic Aptitude Test (SAT) scores when they applied to college."


Additional experimental investigations of delayed gratification in children are reported in Loewenstein, G. and J. Elster, Eds. (1992). Choice over Time. New York, Russell Sage Foundation.

For detailed descriptions of the methods used in the deferred gratification studies, see also: Shoda, Y., Mischel, W. and Peake, P.K. (1990) Predicting Adolescent Cognitive and Self-Regulatory Competencies from Preschool Delay of Gratification: Identifying Diagnostic Conditions. Developmental Psych 26(6): 978-986.

In this study, children (mean age 4 years and 4 months) were tested with marshmallows, pretzel sticks, or poker chips, depending on which the child picked. They were told that the researcher would leave the room, and when he returned the kid could have two marshmallows (or pretzels, or poker chips). The child could ring a bell at any time to bring the researcher back, but if s/he rang the bell s/he could only have one marshmallow. Their mean waiting time was 512.8 sec, with a standard deviation of 368.7 seconds (with no difference according to sex).

The researchers also varied whether the reward was exposed, and whether a tactic of self-distraction was suggested. They would say, for instance: "why don't you think about something fun we could do afterwards while you wait." The unsuggested condition was described as "spontaneous ideation" while a suggested distraction was "suggested ideation" Altogether, they had four possible experimental conditions:





Of these: only the Exposed/Spontaneous differences in delay time in preschoolers was predictive of later traits. The follow up was done around age 18, via parental questionnaires and SAT scores. Questions they asked included: How likely is your child to be sidetracked by minor setbacks? When motivated, how capable is your child of exhibiting self-control in tempting situations? Is planful, thinks ahead? 12 out of 14 were significantly correlated with delay times in these children as preschoolers, but again only under Exp/Spont conditions. SAT Verbal and SAT Math were both correlated as well (correlation = 0.42, p<.05 and .57, p<.001, respectively).

The researchers hypothesized that the exposed/spontaneous ideation conditions are more predictive because intelligent, patient, motivated kids are more likely to develop their own strategies for self-distraction while they wait. When this strategy is suggested/facilitated, or when the rewards are unexposed (presumably providing less of a temptation) the difference in abilities of kids to self-distract is obscured.


A recent paper reported several studies investigating chimpanzee learning:

Study 1 used food: One hand has three raisins, while the other has 5. The researchers tried to train the chimpanzees to chose the smaller of the two quantities in order to receive the largest. After hundreds and hundreds of trials, there was no improvement!

Study 2, on the other hand, used "symbols." Chimpazneess were taught that one pebble represented one raisin. Then chimpanzees were then shown different amounts in different hands with the same rule: pick the smallest number of rocks in order to receive the larger number. Under these condistions the chimpanzees can learn (and relatively quickly).

In Study 3, the researchers used arabic numbers since several of these same chimpanzees know the arabic numerals through about 9. Again, different amounts of food were represented by numbers, with the champanzees having to pick smaller number in order to get the larger payoffg. Again the chimps quickly learn to perform well.

For more information, see: Chimpanzees and their inability to override food passions, Boysen, Sarah T., Kimberly L. Mukobi and Gary G. Berntson. 1999. "Overcoming response bias using symbolic representations of number by chimpanzees (Pan troglodytes)." Animal Learning & Behavior, 27(2): 229-235.


249 Moonraker: 1979. Directed by Lewis Gilbert. Written by Ian Fleming and Christopher Wood.
250 There's Something About Mary: 1998. Directed by Peter and Bobby Farrelly. Written by Ed Decter, John Strauss, Peter Farrelly, and Bobby Farrelly.

For the full text of The Odyssey by Homer (translation by Samuel Butler) with a summary and analysis, see:

See also:


Tzu, Sun. 1984. The Art of War. Oxford University Press.

"Generally, he who occupies the field of battle first and awaits his enemy is at ease, and he who comes later to the scene and rushes into the fight is weary. And, therefore, those skilled in war bring the enemy to the field of battle and are not brought there by him. One able to make the enemy come of his own accord does so by offering him some advantage. And one able to stop him from coming does so by preventing him. Thus, when the enemy is at ease, be able to tire him, when well fed, to starve him, when at rest to make him move." --p. 96, chapter 6.

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