BOB HIRSHON (host):
Strategic miscarriages in monkeys. I’m Bob Hirshon and this is Science Update.
Like lions, male gelada monkeys kill their rival’s offspring when they take over a territory. They also trigger spontaneous miscarriages in pregnant females. This according to Jacinta Beehner, professor of psychology and anthropology at the University of Michigan. Her team observed a population of geladas for five years.
JACINTA BEEHNER (University of Michigan):
Of all the females that could have been pregnant at the time of a takeover, only two females actually gave birth.
They also painstakingly tracked pregnancy hormones in a smaller group, and found clear evidence of takeover-related miscarriages. This phenomenon has been observed before, but until now, it was confirmed only in laboratory rodents. Beehner says that since male geladas typically hold their territory for several years, it makes evolutionary sense for the females to end their doomed pregnancies and start over after a regime change. I’m Bob Hirshon for AAAS, the Science Society.