Final Exam: The Early Age of Mammals

Question 1

The mass extinction event that ended the Age of Dinosaurs happened at the end of what ERA?

Answer 1

Mesozoic

Question 2

When on the geologic time scale was the “Age of Mammals”?

Answer 2

Cenozoic Era

Question 3

Why did the “Age of Mammals” matter (3 big themes)?

Answer 3

1. Big changes in the climate
2. Major extinctions
3. Humans enter (and change) the environment

Question 4

The first evidence of human fossils and activity comes from what era?

Answer 4

Cenozoic era

Question 5

What is a mammal?

Answer 5

vertebrates that make milk

Question 6

It is easy to tell what a mammal is today, but why would it be hard to find evidence of mammals then?

Answer 6

Not likely to see evidence of this (fossil milk), because we aren’t looking at bones and shells, we’re looking at soft parts that are hard to fossilize.

Question 7

What are 2 other unique features of mammals besides the fact they make milk?

Answer 7

1. Three middle ear bones in each ear (in other vertebrates, there is just one)
2. Lower jaw is just one bone

Question 8

When did mammals first evolve/appear? (era and period)

Answer 8

During the Mesozoic era, in the late Triassic period

Question 9

Why is the Cenozoic era called the “Age of Mammals”?

Answer 9

Because the largest land animals have been mammals during that time. (Mammals became dominant)

Question 10

What was the primary reason mammals became dominant in the Cenozoic Era?

Answer 10

The extinction of non-avian dinosaurs allowed mammals to flourish and become the dominant animals on Earth

Question 11

What were mammals like during the Age of Dinosaurs (mesozoic era)?

Answer 11

They were small and lived alongside dinosaurs for over a hundred million years

Question 12

What is an ancestor of mammals?

Answer 12

Cynogathus (a therapsid)

Question 13

What’s an example of a mammal from the triassic period?

Answer 13

Morganucodon

Question 14

T or F: Dinosaurs and mammals both appear at the same time.

Answer 14

True

Question 15

T or F: Mammals drove the dinosaurs extinct.

Answer 15

False; did not

Question 16

When did most major groups of mammals first appear?

Answer 16

early Cenozoic

Question 17

Only about ____% of mammals go extinct during the Cretaceous-Paleogene extinction. So, there was something going on with them that made them survive this extinction better. (This is why they are able to become so dominant after the extinction)

Answer 17

50%

Question 18

What era are we in today?

Answer 18

Cenozoic era

Question 19

What are the 3 periods of the Cenozoic era?

Answer 19

1. Paleogene
2. Neogene
3. Quaternary

Question 20

Paleogene and Neogene together

Answer 20

Tertiary period

Question 21

What period was the “time of recovery” from the Cretaceous-Paleogene extinction?

Answer 21

Paleogene period

Question 22

What are 3 major mammal groups that appear in the early Cenozoic?

Answer 22

1. Primates
2. Bats
3. Early horses

Question 23

Largest meat-eating mammal:

Answer 23

Andrewsarchus

Question 24

Largest land mammal of all time

Answer 24

Paraceratherium

Question 25

The first whales come from _____ ______.

Answer 25

land mammals

Question 26

How were the earliest whales different from whales today? (6 things)

Answer 26

1. limbs more adapted for walking on land (evolved from four-legged land animals)
2. had holes in their skills from predators
3. generally smaller and more elongated body shape
4. teeth were like land mammals, adapted for catching and chewing prey
5. tails more suited for walking motion
6. spent more time on land and may have been semi-aquatic

Question 27

state fossil of Alabama (whale)

Answer 27

Basilosaurus Cetoides

Question 28

3 things to describe the Early Cenozoic life:

Answer 28

1. Palm trees (tropical)
2. Alligators
3. More rain

Question 29

What was the climate like in the early Cenozoic era?

Answer 29

tropical, hot climate and lack of glaciers, causing the sea level to still be higher than it is today.

Question 30

How did the climate change during the Paleocene-Eocene Thermal Maximum?

Answer 30

It got way hotter (raised global temp by more than 5 degrees C, causing mammals to shrink and reptiles to thrive)

Question 31

hottest time during the age of mammals

Answer 31

Paleocene-Eocene Thermal Maximum

Question 32

There was volcanic activity _____ the North American plate due to _______ _______.

Answer 32

within; Yellowstone Hotspot

Question 33

hot spot in mantle beneath continent, far away from tectonic plates.

Answer 33

Yellowstone Hotspot

Question 34

What evidence did the Yellowstone supervolcano eruption leave behind? (4 things)

Answer 34

1. CALDERAS (biggest thing of evidence)
2. Volcanic Deposits (volcanic ash and rocks)
3. Lava Flows
4. Geothermal Features (geysers, hot springs)

Question 35

a large, bowl-shaped depression in the Earth’s surface that forms following a volcanic eruption. (supervolcano creates _____)

Answer 35

caldera

Question 36

Why is it important to study ancient lava flows and historical volcanic activity?

Answer 36

So we can predict if they’ll erupt again and how big the eruptions may be, and analyze patterns.

Question 37

What causes the area around Yellowstone to be volcanically active today?

Answer 37

There is hot mantle material coming up through the mantle; as North America moves west, the volcano will move over a hot spot and erupt. (due to the presence of a hotspot)

Question 38

Could Yellowstone erupt again? What would happen if it did?

Answer 38

Yes; it would be very powerful and have potentially devastating consequences for people living in the area and beyond.