Geotime - Answers

Answer the questions on your paper that are below each graph.

Questions:

1. What is the oldest Era on the scale?

Precambrian

2. Which two Periods are known as the Carboniferous?

Pennsylvanian and Mississippian

3. List the three Periods for the Mesozoic Era.

Triassic, Jurassic, Cretaceous

4. How far back in time does this scale reach?

4.6billion

5. What happened at the end of the Cretaceous?

Extinction

6. When did Dinosaurs first emerge?

Triassic

7. What Era is known as the Age of Mammals?

Cenozoic

8. When did Trilobites exist?

Cambrian-Permian

9. When did Trilobites become extinct?

Permian

10. In what Eon do we currently live?

Phanerozoic

Questions:

1. In what period did the spiny sharks die out?

The end of the Carboniferous

2. In what period did the Ray-fin Fishes expand rapidly?

Paleogene

3. What fishes existed in the Cambrian and Ordovician?

Jawless

Questions:

1. In what age would one find the most diversity in jawless fishes?

Devonian

2. What class of jawless fish died out in the Triassic?

Conodonta

3. Did jawless fishes survive to today?

Yes - Hagfish

Questions:

1. According to the above diagram, did life become more complex over time or less complex over time?

More Complex over time

Questions:

1. What is the largest division of time?

Eon

2. What is the smallest division of time?

Epoch

3. What Epoch do we live in?

Holocene

4. What Eon do we live in?

Phanerozoic

5. What Era did the dinosaurs live in?

Mesozoic

6. What is the oldest documented time on this scale?

3.8bya