books.google.com - To us humans the sex lives of many animals seem weird. In fact, by comparison with all the other animals, we are the ones with the weird sex lives. How did that come to be?Just count our bizarre ways. We are the only social species to insist on carrying out sex privately. Stranger yet, we have sex at...http://books.google.com/books/about/Why_is_Sex_Fun.html?id=svAidQVGbrMC&utm_source=gb-gplus-shareWhy is Sex Fun?