A proper understanding of biology and culture both affirms the great important of biology in human behavior and also explains why biology makes us free. The old equation of biology with restriction, with the inherent (as opposed to the malleable) side of the false dichotomy between nature and nurture, rests upon errors of thinking as old as Western culture itself. The critics of biological determinism do not uphold the equally fallacious (and equally cruel and restrictive) view that human culture cancels biology. Biological determinism has limited the lives of millions by misidentifying their socioeconomic disadvantages as inborn deficiencies, but cultural determinism can be just as cruel in attributing severe congenital diseases, autism for example, to psychobabble about too much parental love, or too little.

How can we distinguish what is biologically determined from what people merely try to justify through biological myths? A good rule of thumb is ‘Biology enables, Culture forbids.’ Biology is willing to tolerate a very wide spectrum of possibilities. It’s culture that obliges people to realize some possibilities while forbidding others. Biology enables women to have children – some cultures oblige women to realize this possibility. Biology enables men to enjoy sex with one another – some cultures forbid them to realize this possibility. Culture tends to argue that it forbids only that which is unnatural. But from a biological perspective, nothing is unnatural. Whatever is possible is by definition also natural. A truly unnatural behavior, one that goes against the laws of nature, simply cannot exist.

I am supposed to be a “nurturist” in the great “nature-nurture” debate, but I find nothing upsetting in this notion of biological influence upon human behavior. I suppose I must also emphasize once again, and for the umpteenth time as we all do, that the categories are absurd and that there is no “nature-nurture” debate as such, the pleasant alliteration of the phrase notwithstanding. Every scientist, indeed every intelligent person, knows that human social behavior is a complex and indivisible mix of biological and social influences. The issue is not whether nature or nurture determines human behavior, for these factors are truly inextricable, but the degree, intensity, and nature of the constraint exerted by biology upon the possible forms of social organization.

A good rule of thumb is ‘Biology enables, culture forbids.’ Biology is willing to tolerate a very wide spectrum of possibilities. It’s culture that obliges people to realise some possibilities while forbidding others.

Our choices are often shaped by our culture and upbringing. They can be so entwined in our routine behaviors and habits that they seem beyond our control.

Whether or not we choose to watch, evolution is shaping us all.

The finding that there is a substantial genetic component to our behavior should not surprise us; indeed, it would be far more surprising if this were not the case. We are products of evolution: among our ancestors, natural selection indubitably exerted a strong influence over all traits that have figured in our survival.

The work of both Piaget and Kinsey suggests that while biology is always a dominant influence on behavior, environment is critical to its expression.

The study of human nature must have profound implications for the study of history, sociology, psychology, anthropology, and politics. Each of those disciplines is an attempt to understand human behavior, and if the underlying universals of human behavior are the product of evolution, then it is vitally important to understand what the evolutionary pressures were.

Ecosystems majorly shape culture — but then that culture can be exported and persist in radically different places for millennia. Stated most straightforwardly, most of earth’s humans have inherited their beliefs about the nature of birth and death and everything in between and thereafter from preliterate Middle Eastern pastoralists.

How can we distinguish what is biologically determined from what people merely try to justify through biological myths? A good rule of thumb is ‘Biology enables, culture forbids.’ Biology is willing to tolerate a very wide spectrum of possibilities. It’s culture that obliges people to realise some possibilities while forbidding others. Biology enables women to have children – some cultures oblige women to realise this possibility. Biology enables men to enjoy sex with one another – some cultures forbid them to realise this possibility. Culture tends to argue that it forbids only that which is unnatural. But from a biological perspective, nothing is unnatural. Whatever is possible is by definition also natural. A truly unnatural behaviour, one that goes against the laws of nature, simply cannot exist, so it would need no prohibition. No culture has ever bothered to forbid men to photosynthesise, women to run faster than the speed of light, or negatively charged electrons to be attracted to each other. In truth, our concepts ‘natural’ and ‘unnatural’ are taken not from biology, but from Christian theology. The theological meaning of ‘natural’ is ‘in accordance with the intentions of the God who created nature’. Christian theologians argued that God created the human body, intending each limb and organ to serve a particular purpose. If we use our limbs and organs for the purpose envisioned by God, then it is a natural activity. To use them differently than God intends is unnatural. But evolution has no purpose. Organs have not evolved with a purpose, and the way they are used is in constant flux. There is not a single organ in the human body that only does the job its prototype did when it first appeared hundreds of millions of years ago. Organs evolve to perform a particular function, but once they exist, they can be adapted for other usages as well. Mouths, for example, appeared because the earliest multicellular organisms needed a way to take nutrients into their bo

Conduct, of course, is possible without science. Humans carried on in their daily affairs long before the first spark of science had been struck. And today there are millions of people living whose actions are not determined by anything we call science. Science, however, could not but gain an increasing influence on human behaviour. To describe this influence roughly and briefly will throw a new light on science. Exaggerating and schematizing the differences, we can say: in the prescientific stage man behaves in a situation as the situation tells him to behave. To primitive man each thing says what it is and what he ought to do with it: a fruit says, "Eat me"; water says, "Drink me"; thunder says, "Fear me," and woman says, "Love me."

Sociobiology is not just any statement that biology, genetics, and evolutionary theory have something to do with human behavior. Sociobiology is a specific theory about the nature of genetic and evolutionary input into human behavior. It rests upon the view that natural selection is a virtually omnipotent architect, constructing organisms part by part as best solutions to problems of life in local environments. It fragments organisms into “traits,” explains their existence as a set of best solutions, and argues that each trait is a product of natural selection operating “for” the form or behavior in question. Applied to humans, it must view specific behaviors (not just general potentials) as adaptations built by natural selection and rooted in genetic determinants, for natural selection is a theory of genetic change. Thus, we are presented with unproved and unprovable speculations about the adaptive and genetic basis of specific human behaviors: why some (or all) people are aggressive, xenophobic, religious, acquisitive, or homosexual.

Human behavior is subject to the same laws as any other natural phenomenon. Our customs, behaviors, and values are byproducts of our culture. No one is born with greed, prejudice, bigotry, patriotism and hatred; these are all learned behavior patterns. If the environment is unaltered, similar behavior will reoccur.