This year marks the 25-year anniversary of the publishing of E.O. Wilson'sseminal book "Sociobiology." Wilson's theory of sociobiology, today usuallyknown as evolutionary psychology, is the idea that the human mind is partlyshaped by evolutionary influences.

In the quarter-century since Wilson'sbook was published, the theory has generated some of the most heated, andmost politicized, scientific debate of our time. Some mistook the theory asa scientific validation of the contention that some people are born with"weak" minds, have a proclivity for crime, and so on. Others viewedevolutionary psychology as a threat to religious and moral values. In atimewhen DNA is being sequenced and it is increasingly common toattribute behavior to genes, Wilson's idea demands another look: especiallysince it may be that faith and morals make sense even if sociobiology isright.

The basic premise of evolutionary psychology is that the mind, like anyother organ of the human body, has been shaped by natural selection duringthe course of evolution, creating biological roots to human nature. Just asour ability to, for instance, walk on two feet proved advantageous in theancestral environment and was therefore favored by natural selection, ourancestors' fear of wild animals helped them to survive--explaining,sociobiology assumes, the animal phobias so many people have today.

But the theory doesn't stop there. The same kind of logic, say evolutionarypsychologists, explains other facets of human psychology. On anevolutionarylevel, the theory says, the main thing human beings care about is passingoncopies of their genes. We can better understand negative emotions likegreed, lust, anger, guilt, and jealousy by considering how they might havehelped our ancestors survive and pass on their genes. By the same token,thegood things we do--charity, love and marriage, and altruism--can be explainedas evolutionarily driven mechanisms in the service of our overarching goalof "reproductive success."

Thus the good and the bad of humanity is less amatter of individual choice than a matter of deeply programmed evolutionarydrives. Does that invalidate our religious and charitable impulses?Consider what evolutionary psychology--which is now catching on as atheory ofchoice at many universities after years of resistance--hasto say about some of our most cherished practices:

Charity. Evolutionary psychology says that insofar as people engage incharity, most do so to gain status and look good in front of others--atleaston a subconscious level. Most philanthropic donations are not anonymous,forinstance. Studies show that people are drastically less likely to givebloodif not given a sticker from the Red Cross that says, "I gave blood."

Theconclusion: People give so they can appear to be friendly and compassionatein front of other people, thus increasing their chances of appearing fit topotential mates.

Love and marriage. Men and women get married not for love of each other, orlove of children, but as a deterministic means of propagating their genestotheir offspring. In evolutionary terms, men use women for their eggs, whichis why men prefer women who are young--the young are more fertile. On aninstinctual level, men are driven to want to sleep around rather than stayfaithful to wives. This is explained in terms of parental investment. For aman, fathering a child requires a negligible amount of effort, so theoptimal strategy for spreading his genes is to have as much sex aspossible.

In the ancestral environment, men who slipped out in the night to have sexwith women other than their wives passed on more copies of their genes thanmen who didn't. That's why men are that way today. They have beengenetically predisposed to cheat.

For women, marriage is mainly a way to secure resources for children.That'swhy women tend to be attracted to men with status and wealth--the more moneya man has, the better provided for her children are likely to be. Since thewoman is the one who actually has to carry the child, for her being aparentrequires a huge amount of time, energy, and resources. Therefore, she has tobe choosy about who she picks as her mate, which is why women are lesspromiscuous than men.

This is evolutionary psychology's view of relations between the genders--men want lots of quick sex without responsibility, women want power andmoney. Not exactly a heartwarming picture.

Altruism. True and selfless altruism--doing something for someone withoutexpecting to get anything in return--is rare. Instead, says sociobiology, wemostly practice "reciprocal altruism," doing something for somebody becausewe know that when the time comes the favor will be returned: "You scratchmy back, I'll scratch yours." We also practice "kin selection," helping peoplerelated to us. In evolutionary terms, doing a favor for a relative isactually a selfish act: By promoting the welfare of our relatives,we're promoting genes that are at least partly ours.