... animal behavior in general and human behavior in particular. Both sex, meaning the genetic distinc-tion between male and female, and gender, referring to its social and po-litical associations, ... a thoughtful and insightful reader and editor. Several chapters were written while I was a Visiting Professorin the Department of Animal Ecology at Uppsala University in Sweden, and I am very ... my stay and for the support of the Swedish Natural Science Re-search Council. Other scientists in Finland, Norway, and Sweden gra-ciously discussed their work with me during my visit and gave...