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Question 1

How new species arise?

Answer 1

A barrier that prevents gene flow

Question 2

allopatric speciation?

Answer 2

When the ancestral population is physically divided into two populations by a geographic barrier.

Question 3

Peripatric speciation?

Answer 3

When a small subset of individuals are separated from the main population by a geographic barrier and isolated to a new location (founder).

Question 4

Parapatric speciation?

Answer 4

Occurs when species are spread out over a large geographic area, but mate only with those that live close to them.

Question 5

Sympatric speciation?

Answer 5

Occurs within a population when a small subset exploit a new niche and mate only with others within that niche.

Question 6

Speciation events that use geographic barriers?

Answer 6

Allopatric and Peripatric

Question 7

Originations?

Answer 7

Origins of species that result from speciation events

Question 8

Background rate?

Answer 8

Ordinary extinction with a variety of causes: changing climate, loss of food recourse, predation, disease, competition, loss of habitat, etc

Question 9

Sepkoski’s curve?

Answer 9

*X axis: time
*Y axis: number of marine invertebrate families

Question 10

Standing diversity (starting diversity) T2?

Answer 10

Standing diversity T1 + originations T1 - extinctions T1

Question 11

How to compute standing diversity of current stage?

Answer 11

*Count the standing diversity at the beginning of the previous stage
*Count the number of originations during the previous stage
*Count the number of extinctions during the previous stage

Question 12

The permian mass extinction occurred how many years ago?

Answer 12

250Mya

Question 13

In the permian mass extinction, how many species were lost?

Answer 13

96% of species

Question 14

The Cretaceous Paleogene extinction occurred how long ago?

Answer 14

65Mya

Question 15

How many species were lost in the Cretaceous Paleogene extinction?

Answer 15

75% of species, which killed all non-avian dinosaurs

Question 16

Why was the permian extinction important?

Answer 16

It nearly wiped out all life.

Question 17

In what extinction did he trilobites go extinct?

Answer 17

Permian extinction

Question 18

What caused the permian extinction?

Answer 18

Largest volcanic eruption ever in Siberia.

Question 19

What marked the end of the mesozoic?

Answer 19

The Cretaceous Paleogene extinction.

Question 20

Adaptive radiation?

Answer 20

Rapid diversification into many forms over a short period of time.

Question 21

Key innovations?

Answer 21

Evolutions of novel traits and phenotypes that drive adaptive radiations.

Question 22

Tempo in evolution?

Answer 22

The timing or rate in which evolution occurs.

Question 23

Mode in evolution?

Answer 23

How evolution occurs

Question 24

Evolution is a change in ________ within a population over time.

Answer 24

Allele frequencies

Question 25

Time by morphology plots?

Answer 25

*Y axis: Time from old to young. Start of the line is the origination and end is extinction.
*X axis: change in morphology

Question 26

Angiogenesis?

Answer 26

gradual change overtime within a single lineage.

Question 27

Cladogenesis?

Answer 27

Subpopulation diverged and developed new traits.

Question 28

Anagenesis?

Answer 28

Gradual evolution within a single lineage. It is driven by continuous directional selection.

Question 29

Stasis?

Answer 29

Long periods where most species do not change much, and then rapid busts of evolutionary change.

Question 30

What is one explanation to why there are gaps of no transitional evolution and then sudden change?

Answer 30

Stasis

Question 31

Did paleontologists prior to 1970’s believe the idea of stasis?

Answer 31

No, they believed that there was an incompleteness in the fossil record which lost the transitional evolution fossils.

Question 32

Punctuated equilibrium? 3*

Answer 32

Morphological change occurs relatively rapidly associated with splitting of lineages.

Gaps are not just due to an incompleteness in the fossil record with a lot of missing transitional fossils that will show anagenesis.

Stasis is common

Question 33

Phyletic gradualism?

Answer 33

Anagenesis causes species to evolve continuously and gradually over time. The gaps in the fossil record are due to an incomplete fossil record.

Question 34

Possible causes for stasis? 2*

Answer 34

*Fluctuating selection, perhaps tracking a changing environment?

*Constants? Limits or biases in the production of variation due to morphology or genetics.

Question 35

How does evolution actually proceed?

Answer 35

*Over short evolutionary time, gradualism and anagenesis are common. Adaptive radiations occasionally occur over short evolutionary time. The fossil record holds some examples of gradualism over longer evolutionary time.

Question 36

Why is the Anthropocene important?

Answer 36

When human hunter gatherers transition to civilization and agriculture. It had a significant important to the planet and could be the start of the 6th mass extinction.