Second Nature, by Haim Ofek. It was written in 2001. It tries to address some puzzles in evolution and in ancient economic history. For example, why is the human brain overdeveloped, in the sense that it is larger than necessary to enable humans to secure their ecological niche? I suspect that if it had come out in the past two years the book would have been much more widely read, propelled by economics blogs.
Meir Kohn sent me an email recommending the book. He did so because Ofek argues that the human propensity to trade with strangers goes way back.