Life looked different after an asteroid crashed into the planet around 66 million years ago. The dinosaurs died out, the arboreal mammals declined, and the terrestrial mammals thrived. The traditional ...

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A tiny mammal called Cimolodon desosai from the dinosaur era is helping scientists understand how mammals survived extinction ...

Researchers suggest that ground-based mammals fared better than their arboreal relatives during the end-Cretaceous extinction thanks to their lifestyle. Reading time 2 minutes The end-Cretaceous ...

Mammals and dinosaurs coexisted on Earth until a catastrophic event 66 million years ago killed 75% of life on the planet.

NEW YORK — Maybe you learned this in school: The big dinosaur die-off 65 million years ago was a liberation for mammals, and they quickly produced a bunch of new species that included ancestors of ...

Learn about a small rodent-like mammal whose descendants survived the extinction event that killed all non-avian dinosaurs.

A newly discovered prehistoric mammal may hold clues to how life survived the dinosaur-killing extinction. The tiny species, ...

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. New ...

Latest research has revealed that first mammals and first dinosaurs appeared on earth at about the same time and that the ancestral mammals underwent dramatic evolution while challenging the dinosaurs ...

WASHINGTON - They just needed some legroom: New research shows the great dinosaur die-off made way for mammals to explode in size - some more massive than several elephants put together. The largest ...

This is a Hadrosaurid (duck-billed dinosaur) jaw with dental battery of Edmontosaurus. This image relates to a paper that appeared in the Oct. 5, 2012, issue of Science, published by AAAS. The paper, ...