Human Zoo and Naked Ape, Desmond Morris. Older books, maybe early '70s? Good stuff though.
Also, Nickled and Dimed On (Not) Getting By in America, Barbara Ehrenreich. This chick (a newspaper writer) took like 2 yrs off and joined the working poor in Minneapolis and somewhere else, Wilmington maybe. Anyhoo, just took entry level jobs (serving, house cleaning, etc) and tried to get by on minimum wage. Shits interesting as hell. Really good book.