31.2-biology

1.

10 points

Biologists sometimes refer to birds as feathered __________.

2.

10 points

Like reptiles, birds have clawed toes and _______ scales on their feet.

3.

10 points

Even with good care, ___________ wear out and must be replaced.

4.

10 points

Flight requires high levels of ___________.

5.

10 points

An __________ is an animal that maintains a nearly constant body temperature that is not dependent on the environmental temperature.

6.

10 points

____________ reduce heat loss in cold temperatures.

7.

10 points

Birds, like reptiles, reproduce by internal _______ and lay amniotic eggs usually inside a nest.

8.

10 points

_____________ are flightless birds with wings and feet modified for swimming and a body surrounded with a thick layer of insulating fat.

9.

10 points

Scientists hypothesize that today's birds are derived from an evolutionary line of dinosaurs that did not become __________.

10.

10 points

Fossil finds in __________ support the idea that birds evolved from a theropod dinosaur.