New fossils of a chipmunk-sized animal that lived about 85 million years ago suggest that placental mammals arose much earlier than is generally believed and thrived for millions of years alongside ...

Around 100 million years ago, a remarkable evolutionary shift allowed placental mammals to diversify and conquer many cold regions of our planet. New research from Stockholm University shows that the ...

Biochemical ‘DNA methylation’ marks are found across the genome in vertebrate animals, but in the early embryos of placental mammals, such as mice and humans, they are largely erased in a ‘system ...

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 ...

More mammals were living on the ground several million years before the mass extinction event that wiped out the dinosaurs, new research has revealed. More mammals were living on the ground several ...