Before the asteroid hit, Steve described mammals as “staying and diversifying in the shadows” while dinosaurs “eventually took over from the crocodiles, got bigger and spread around the ...
The fight scene, preserved in a fossil discovered in China, suggests that small mammals preyed on the dinosaurs that ruled Earth during the Cretaceous period more than previously thought ...
Although they came into their own only after the extinction of the dinosaurs some 65 million years ago, mammals had maintained a low-profile existence for some 150 million years before that.
Faced with an evolving group of competing organisms -- the mammals -- perhaps dinosaurs were driven to extinction by competition. Packs of small mammals would have competed with dinosaurs for food.