Page 177 - The Dinosaur Book and Other Wonders of the Prehistoric World (DK-Smithsonian)

Megazostrodon Resembling a modern
shrew, Megazostrodon
probably preyed on worms
and other invertebrates.

Zalambdalestes Repenomamus

Morganucodon was only 4 in (10 cm)
long, and probably hunted at night for
insects such as beetles. The first mammals
Morganucodon
Fruitafossor

Repenomamus had
sharp teeth and
powerful jaws.
Repenomamus

One
fossil of
Repenomamus
shows the remains
of a baby dinosaur
in its stomach.

The short, strong legs enabled
Repenomamus to forage for
food across a wide area.

reptile ancestors and like the modern platypus. Placental mammals, which bear well-developed
Living mammals that breed like this are called babies, appeared a little later, about 90 million
monotremes. But later in the Mesozoic Era, years ago. All three types of mammal survived
animals like Sinodelphys started bearing live the mass extinction that ended the Mesozoic
young in the same way as modern kangaroos Era, and the survivors became the ancestors
and other pouched mammals (marsupials). of all modern mammals. 175

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