my current book on tape is Sapiens, which I guess everyone is reading, at least in airports. I think so far my favorite idea is that homo sapiens excelled over other homo-species through a cognitive revolution fueled by our love of gossip.
also the idea that we still have no idea whether homo sapiens became the only homo-species left on the planet because we either inbred with them OR committed very efficient genocide. were early humans lovers or murderers?? no one knows, because we're super likely to do either. homo sapiens, amirite?