Despite not being particularly mammal-looking, the earliest true mammals began to rise about 200 million years ago, when dinosaurs were still roaming Earth. However, the therapsids still had important ...

Before the time of the dinosaurs, a naked, warm-blooded egg-layer known as a gorgonopsian sipped water from Pangea's tropical floodplains amid herb-grazing reptiles off what's now Mallorca in the ...