David Coleman of Collaborate.com
"I heard it said that anytime you want to make a team have higher performance… just add a woman. I am not sure where I heard that, it was probably from some recent Harvard study. Kenneth Mikkelsen and Jeppe Vilstrup Hansgaard from Innovisor, a Danish consulting company who not only sent me some of their research but also noted articles on this topic in the Wall St. Journal , Management-Issues.com, The BBC radio (next week) and the Proceedings of the Royal Society. Basically what they have found is that testosterone disrupts collaboration, people (mostly men) act more egocentrically, and act less cooperatively."