Final Exam: The Age of Humans and the "6th Extinction"

Question 1

What happened to animal species as humans began to colonize islands?

Answer 1

Animal species were going extinct

Question 1

Humans arrived at most ______ in the more ______ past. Why?

Answer 1

islands; recent; because it’s harder to get there

Question 2

What type of species mostly went extinct on islands after human arrival? Why?

Answer 2

Bird species; many flightless birds on islands which makes them very vulnerable

Question 3

Why were there flightless birds on islands?

Answer 3

they didn’t need to use their wings anymore, so they saved energy by not flying and eventually became flightless

Question 4

Why were extinctions easier on islands?

Answer 4

Smaller space

Question 5

T or F: Extinctions have resumed on continents over past few centuries.

Answer 5

True

Question 6

What animal is this:
- went extinct 1914
- lots of these birds in North America back then

Answer 6

Passenger Pigeon

Question 7

What animal is this:
- went extinct 1918
- lots of these lived over large areas in North America back then
- targeted to be eliminated for eating farmer’s crops

Answer 7

Carolina Parakeet

Question 8

compares modern extinctions to the “Big 5” in Earth’s history.

Answer 8

Sixth Extinction Hypothesis

Question 9

Are We in a “Sixth Mass Extinction” Right Now? This depends on…

Answer 9

how you define a mass extinction, and what will happen in the future.

Question 10

What is the challenge in determining if we are in a sixth mass extinction?

Answer 10

Proving if species are extinct; (some species, such as the ivory billed woodpecker, are secretive and it’s hard to determine if they’re extinct)

Question 11

Why do some researchers say we are living through the “sixth mass extinction”?

Answer 11

The rate of extinction is high and it’s leading to a significant loss in biodiversity

Question 12

Are more species going extinct now than in past mass extinctions? Are species going extinct faster or slower than in the past?

Answer 12

• Yes
• Faster than in the past

Question 13

1. What are the 4 parts of the Earth System?
2. Are they all interconnected? Do humans have a global influence on the Earth System?

Answer 13

1. Biosphere, Geosphere, Hydrosphere, Atmosphere
2. Yes; yes

Question 14

Humans are part of what part of the Earth System?

Answer 14

Biosphere

Question 15

How have humans affected the biosphere? (2)

Answer 15

• created new forms of life through artificial selection
• extinctions

Question 16

How have humans affected the geosphere?

Answer 16

• mining is moving massive amounts of rocks

Question 17

How have humans affected the hydrosphere?

Answer 17

building dams → changing a river into a lake → affects evaporation and sediment deposition

Question 18

How have humans affected the atmosphere?

Answer 18

Burning fossil fuels

Question 19

a proposed new part of the geologic time scale defined by powerful global human influence.

Answer 19

Anthropocene

Question 20

The Anthropocene would be an _____ of the Quaternary period.

Answer 20

epoch

Question 21

T or F: The Anthropocene wouldn’t affect the geologic time scale how we learned it

Answer 21

True

Question 22

Including the anthropocene, the Quaternary period would be epochs of ________, ________, and _________.

Answer 22

• pleistocene
• holocene
• anthropocene

Question 23

• What time has been proposed as the start of the Anthropocene?
• Why (4 things)?

Answer 23

• 1950
  1. Human population growth (over 8 billion people now)
  2. Carbon Dioxide levels increase
  3. Global temperature rises
  4. Sea level steadily going up

Question 24

_____ _______ are used to relate rock layers that are continents apart.

Answer 24

index fossils

Question 25

What clues are we leaving behind in the rocks for future geologists to find?

Answer 25

Plastic, nuclear waste, footprints, etc.

Question 26

Radioactivity from nuclear tests is detectable in ______ and ______ from 1950 onward.

Answer 26

sediment; corals

Question 27

Why is plastic a good clue for future geologists to find that show our existence?

Answer 27

because there is no natural plastic in the world; it is human made.

Question 28

where plastic is bonding sediments together

Answer 28

Plastiglomerates

Question 29

could mark the start of a new Anthropocene epoch; proposed defining location

Answer 29

Crawford Lake in Ontario

Question 30

Why did the Anthropocene get rejected?

Answer 30

because it’s tough to pinpoint when humans’ impact on the planet began.