The Friends of Charles Darwin

Too many males may have been the reason the dinosaurs died out 65 million years ago, say Leeds University researchers. They believe that dinosaurs may have been like modern-day reptiles such as crocodiles whose sex depends upon the temperature before they were born. The new idea is that the asteroid that struck changed the world's climate causing it to be cooler, which led too many dinosaurs to be born male. The male-female imbalance would have led to their extinction, they say.