Page 176 - The Dinosaur Book and Other Wonders of the Prehistoric World (DK-Smithsonian)

The first mammals Fruitafossor

Fruitafossor was
a squirrel-sized
burrowing animal.

This insect-eater may
have used its strong
front limbs to break
into termite nests.

Sinodelphys

This earliest known pouched Zalambdalestes
mammal lived 125 million years The long back legs of this
ago in what is now China. insect-eating mammal were
adapted for hopping like a rabbit.

Eozostrodon

The short limbs of Eozostrodon
suited life in burrows, where it hid
away from predatory dinosaurs
during the day.

The earliest mammals appeared in the late undergrowth, or even underground, preying
Triassic Period, about 205 million years on insects and small animals. The largest of
ago. Over the next 140 million years mammals these secretive creatures, Repenomamus,
lived in the shadow of their dinosaur neighbors. was no bigger than a badger. The earliest
They were small, probably nocturnal creatures mammals—animals like Morganucodon and
174 that spent most of their time hiding in dense Eozostrodon—would have laid eggs like their

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