Starre Julia Vartan

One of the keys to Darwin’s theory of Sexual Selection was that male mammals are always larger. But, it turns out they’re not, as I reported on for New Scientist. Researcher Kaia Tombak at Hunter College in New York found this out when she took the time to measure hundreds of mammal species using the same criteria:

“Male mammals have long been said to be larger than females – a phenomenon known as sexual dimorphism – but it turns out that may not be the norm. An analysis of the body mass of over 400 mammal species revealed that only about 44 per cent had larger males.”

I’ve interviewed Tombak more extensively on this subject for my forthcoming book. Read the full story on New Scientist here.