Chapter 9

Question 1

Taphonomy and sampling bias

Answer 1

Difference between what was once alive being over/under represented in the fossil records

Question 2

Mass extinction

Answer 2

Over 60% of species going extinct within a million year span

Question 3

Fossils

Answer 3

Amber and freezing (minimal change), permineraliza*on and replacement, molds and casts, trace fossils

Question 4

Subduction of older rock bias

Answer 4

Fossils being difficult to access due to change in tectonic plates

Question 5

Collection bias

Answer 5

People only looking for the more ‘exciting’ fossils

Question 6

Lagerstätte

Answer 6

An area containing a bunch of really well-preserved fossils, even some soft tissues

Question 7

Ediacaran Biota

Answer 7

Possible bilateral symmetry

Question 8

Cambrian Explosion

Answer 8

Either rapid change over a short
time period (~20 million), or slow change over long period (50 million years). Increased diversity of marine life followed by colonization of land due to rising oxygen concentrations in seawater

Question 9

I

Answer 9

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Question 10

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Answer 10

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Question 11

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Answer 11

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Question 12

Permian extinction event

Answer 12

All trilobites disappeared, caused by tons of volcanic activity = increase in CO2, decrease in O2, change in temp 252.3 MYBP

Question 13

Cretaceous-Paleogene extinction event (K-T or K-Pg)

Answer 13

65.5 MYBP, Meteor colliding with earth. Rapid mamilian diversification and origination afterwards

Question 14

Mammal-like reptiles are a group of tetrapods that show a number of similarities to modern-day mammals. Explain one of these.

Answer 14

A bony secondary palate that separated the breathing and chewing functions in the oral cavity