Mass Extinctions

Question 1

What is the first mass extinction that happened 440 million years ago? What caused it, and what evidence do we have?

Answer 1

Ordovician-Silurian: water levels dropped because the glaciers locked up all the water.

Question 2

What was the second mass extinction that happened 360 million years ago? What caused it, and what evidence do we have?

Answer 2

Late Devonian: pulses lasting 100,000-300,000 years caused radioactive material to be released in the water, which was poisonous to the marine animals.

Question 3

What was the third mass extinction that happened 250 million years ago? What caused it, and how do we know?

Answer 3

Permian-Triassic: flood volcanism that may have occurred in the Siberian Traps in Russia.

Question 4

What was the fourth mass extinction that happened 200 million years ago? What caused it, and how do we know?

Answer 4

Triassic-Jurassic: climate change, or lava flooding

Question 5

What’s the fifth mass extinction that happened 65 million years ago? What caused it and how do we know?

Answer 5

Cretaceous-Tertiary: asteroid impact, a crater has been found off the Yucatan Pennisula

Question 6

What’s the sixth mass extinction happening right now? What is causing it and how do we know?

Answer 6

No name, but evidence shows a direct relationship between human activity and the destruction of thousands of species annually.