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But when she examined the record of history, Betzig was stunned. Her simplistic prediction that power is used for sexual success was confirmed again and again. Only in the past few centuries in the West has it failed. Not only that, in most polygamous societies there were elaborate social mechanisms to ensure that a…
Let us erect the four commandments of mating system theory. First, if females do better by choosing monogamous and faithful males, monogamy will result—unless, second, men can coerce them. Third, if females do no worse by choosing already-mated males, polygamy will result—unless fourth already-mated females can…
There are five ways to find out. One is to study modern people directly and describe what they do as the human mating system The answer is usually monogamous marriage. A second way is to look at human history and divine from our past what sexual arrangements are typical of our species. But history teaches a dismal…
Low was looking to explain why young women have fat on their breasts and buttocks more than on other parts of their bodies. The reason this requires explaining is that young women are different from other human beings in this respect. Older women, young girls, and men of all ages gain fat on their torsos and limbs…
There are many well-established natural factors that bias the sex ratio of human offspring, proving that it is at least possible. The most famous is the returning-soldier effect. During and immediately after major wars, more sons are born than usual in the belligerent countries as if to replace the men that died…
Trivers and Willard realized that the same general principle of sex allocation, which determines the gender of nematodes and fish, applies even to those creatures that cannot change sex but that take care of their young. They predicted that animals would be found to have some systematic control over the sex ratio of…
Another insect, a scale insect, has an even more bizarre genetic parasite. When its eggs are fertilized. sometimes more than one sperm penetrates the egg. If this happens, one of the sperm fuses with the egg's nucleus in the normal way; the spare sperm hang around and begin dividing as the egg divides. When the…
Many fungi are sexual, but they do not have males. They have tens of thousands of different sexes, all physically identical, all capable of mating on equal terms. but all incapable of mating with themselves. Even among animals there are many, such as the earthworm, that are hermaphrodites. To 3e sexual does not…
Again and again in recent years evolutionary biologists have found themselves returning to the theme of parasites. As Is Richard Dawkins put it in a recent paper: "Eavesdrop [over] morning coffee at any major centre of evolutionary theory today, and you will find 'parasite' to be one of the commonest words in ti the…
Biologists have persistently overestimated the importance of physical causes of premature death rather than biological ones. In virtually any account of evolution, drought, frost, wind, or starvation looms large as the enemy of life. The great struggle, we are told, is to adapt to these conditions. Marvels of physical…
In 1966, George Williams exposed the logical flaw at the heart of the textbook explanation of sex. He showed how it required animals to ignore short-term self-interest in order to "further the survival and evolution of their species, a form of self restraint that could have evolved only under very peculiar…
The chessboard is the world; the pieces are the phenomena of the universe; the rules of the game are what we call the laws of Nature. The player on the other side is hidden from us. We know that his play is always fair, just, and patient. But also we know. to our cost, that he never overlooks a mistake or makes the…
In recent years the geneticists have turned away from good mutations and begun to think about bad ones. Sex, they suggest, is a way of getting rid of bad mutations. This idea also has its origins in the 1960s, with Hermann Muller, one of the fathers of the Vicar of Bray theory. Muller, who spent much of his career at…
A gazelle on the African savanna is trying not to be eaten by cheetahs, but it is also trying to outrun other gazelles when a cheetah attacks. What matters to the gazelle is being faster than other gazelles, not being faster than cheetahs. (There is an old story of a philosopher who runs when a bear charges him and…
The relationship between a mother and her child is fairly straightforward: Both are seeking roughly the same goal—the welfare of themselves and each other. The relationship between a man and his wife's lover or between a woman and her rival for a promotion is also fairly Straightforward: Both want the worst for each…
One of the peculiar features of history is that time always erodes advantage. Every invention sooner or later leads to a counterinvention. Every success contains the seeds of its own overthrow. Every hegemony comes to an end. Evolutionary history is no different. Progress and success are always relative. When the land…
It IS a mistake that biologists used to make, too. They believed that evolution proceeded by accumulating the changes that individuals gathered during their lives. The idea was most clearly formulated by Jean-Baptiste Lamarck, but Charles Darwin sometimes used it, too. The classic example is a blacksmith's son…
Humanity is, of course, morally free to make and remake itself infinitely, but we do not do so. We stick to the same monotonously human pattern of organizing our affairs. If we were more adventurous, there would be societies without love, without ambition, without sexual desire, without marriage, without art. without…
rhe systematic development of knowledge and technology that we all 'science' originated in the millennia of prehistory, and early vomen were among these first 'scientists'. They invented tools, accumulated knowledge about edible and medicinal plants, and 3robably discovered 'the chemistry of pot-making, the physics of…
We stand upright-after a little practice-on a ship that rolls because we possess an array of sensory nerve cells buried in our muscles, skin, and joints. The function of these sensors is to provide a constant flow of information to the brain about the movements and location in space of the various parts of our bodies…