Question

1.

Compared with the Eocene, the Oligocene was characterized by

warmer, more consistent temperatures.

a change in the Northern Hemisphere from deciduous to tropical forests.

colder, more variable global temperatures.

the rise of a land bridge connecting North and South America.

2.

Many paleontologists focus on teeth for several reasons, including that

teeth are continuously remodeled throughout life, so they show the response an animal had to the environment in which it lived.

teeth are not remodeled during life, so they carry a record of the animal’s entire life history.

although the shape of teeth tells us little about diet, the wear on them indicates what the animal ate.

although teeth are the least likely body part to survive, they can be dated using the argon–argon method.

Answer 1

1. Oligocene was characterized by the rise of a land bridge connecting North and South America.

It was during the Oligocene that mountain building in western north America continued and South America finally separated from Antartica and moved north, towards North America.

2. The tissues and forms of teeth are adapted to surviving a lifetime of changes; and are subjected to continuous physical and chemical attack. Teeth are tough and durable structures.

Answer: teeth are continuously remodeled throughout life, so they show the response an animal had to the environment in which it lived.