Chapter 17: Phanerozoic Eon

Question 1

Characteristics of the Cambrian Period 542-488mya

Answer 1

• Rodinia
• Life was only in the sea, not on land (species evolve quickly)
• Extinction in this time was due to competition, glacial cooling, oxygen depletion

Question 2

Characteristics of the Ordovician Period 488-444mya

Answer 2

• Gondwana covered in glaciers
• Lots of volcanoes due to subduction= CO2
• Greenhouse period, sudden short lived intense glaciations ended the greenhouse conditions
• Life flourished
• 2 extinction events
• In the end, all the glaciers sucked up the water, niches eliminated

Question 3

Characteristics of the Silurian Period 444-416mya

Answer 3

• Still ice sheets
• Higher sea levels and more abundant warm shallow seas
• Greenhouse period
• Sea life moved onto land

Question 4

Characteristics of the Devonian period 416-359 mya

Answer 4

• Europe, NA and Asia all joined
• Some glaciers
• CO2 consumed fast by growing forests (cooling)
• The age of fish, developed strong lungs and could crawl in and out of water
• Plants developed seeds
• 370 extinction caused by an asteroid
• 360 extinction caused by anoxia due to algal decay

Question 5

Characteristics of the Carboniferous period 359-299 mya

Answer 5

• Icehouse, glaciation= low sea levels
• Production of the largest coal deposits ever made
• fish evolved into amphibians
• Mild extinctions due to climate and sea level issues

Question 6

Characteristics of the Permian period 299-251 mya

Answer 6

• Pangea formed
• Rich in marine and terrestrial life
• Conifer trees evolved
• Lizard-like creatures dominated + diversified
• Oxygen catastrophe ????

Question 7

Characteristics of the Triassic Period 251-201.6 mya

Answer 7

• Pangea slowly drifting apart creating new oceans+ shallow water environments
• No glaciation
• Age of the reptiles
• ended the period with one mass extinction due to anoxic events

Question 8

Characteristics of the Jurassic Period 201.6-145.5 mya

Answer 8

• More spreading center volcanism= more CO2, strengthening the greenhouse
• no glaciation
• Warm oceans= plankton devlopped
• Golden age for dinos

Question 9

Characteristics of the Cretaceous period 145.5-65.5 mya

Answer 9

• Pangea was broken up
• Chalky because of all the shell organisms
• Worlds largest petroleum deposit formed by marine organisms

Question 10

Characteristics of the Cenozoic Era 65.5-Now

Tertiary period 65.5-2.6 mya

Answer 10

• Fragments continue to drift away
• heading towards an Icehouse
• Reptile were replaced by mammals after the extinction
• Most of the vegetation was burned= great fertilizer for plants to flourish
• PETM event casued 35-50% loss of marine species

Question 11

Characteristics of the Quaternary period 2.6-Now

Answer 11

• Icehouse

- Holocene mass extinction is widespread and on going