Sex Differences
How do nature and nurture conspire to produce average differences between men and women? How different are the sexes, anyway? Are we highly dimorphic like peacocks and deer? Or are we relatively monomorphic, like gibbons and sea dragons?

And why is research on sex differences so controversial? Do people react more negatively to research findings that favour males than those that favour females? Our recent research suggests that they do...

The Evolution of Human Altruism
If evolution is all about the survival of the fittest, why are people usually quite nice to each other? Do humans, like most other animals, help relatives more than non-relatives? If natural selection favours organisms that preferentially help their relatives, why are we often so nice to friends, romantic partners, and other unrelated individuals?

The Nature and Nurture of Individual Differences
Why are people the way they are? To what extent are the differences between individuals due to differences in genes vs. differences in upbringing and experience? Is the answer to this question the same in less developed countries as it is in more developed ones?

The Philosophical Implications of Evolutionary Theory
Steve Stewart-Williams' first book came out in 2010. It's called Darwin, God, and the Meaning of Life, and it's about the implications of evolutionary theory for some of the central topics in philosophy: Is there a God? Does life have any ultimate meaning or purpose? Are human beings superior to other animals or is this just a human prejudice? Does evolutionary theory have implications for issues like euthanasia and animal rights? Does the theory imply that ultimately nothing is morally right or wrong?