As for testosterone, it's gotten a bum rap. Yes, it has tons to do with aggression but it doesn't cause aggression as much as sensitizes you to the environmental triggers of aggression.

Yes, genes are important for understanding our behavior. Incredibly important - after all, they code for every protein pertinent to brain function, endocrinology, etc., etc. But the regulation of genes is often more interesting than the genes themselves, and it's the environment that regulates genes.

In terms of the most unique thing we do socially, my vote goes to something we invented alongside cities - we have lots of anonymous interactions and interactions with strangers. That has shaped us enormously.

Robert Sapolsky Quotes