GENTLE GIANTS WOO MORE LADIES (IN MICE, ANYWAY)

http://www.eurekalert.org/pub_releases/2009-02/uocp-hcp021909.php

Sometimes the nice guy gets the girls. At least that's how it is for striped mice. A research team led by Carsten Schradin (University of Zurich and University of the Witwatersrand) studied the breeding strategies of striped mice in South Africa. They found that dominant males who controlled breeding groups had lower testosterone levels than subdominant males. "What is unusual about this society is that the dominant males are in fact the most sociable, often grooming other group members," Schradin says. "It is the smaller and solitary living males, which roam from one group to another, that have the highest testosterone levels." The roaming males try to coerce females to mate, which, as one might imagine, is less successful than establishing a breeding group.

Carsten Schradin, Michael Scantlebury, Neville Pillay, and Barbara König, "Testosterone levels in dominant sociable males are lower than in solitary roamers: physiological differences between three male reproductive tactics in a sociably flexible mammal," 173:March