Chapter 4.3

Question 1

What can biological species that are isolated not do?

Answer 1

Interbreed

Question 2

What does reproductively isolated mean?

Answer 2

When biological species can not interbreed. ex. Frogs and Elephants

Question 3

What would populations that breed during different time periods be known as?

Answer 3

Reproductively Isolated

Question 4

What is Speciation?

Answer 4

The formation of new species

Question 5

What are the two methods of Speciation?

Answer 5

Transformation and Divergence

Question 6

What is transformation?

Answer 6

When a new species gradually develops as a result of mutation and adaptation to changing environmental conditions and the old species is gradually replaced

Question 7

What would happen if Speciation only happened through Transformation?

Answer 7

The total number of diversity would remain unchanged

Question 8

What is Divergence?

Answer 8

When one or more species arise from a parent species that continues to exist

Question 9

What are the pathways to Speciation a result of?

Answer 9

Natural Selection

Question 10

What must happen for speciation to occur?

Answer 10

The populations must be prevented from interbreeding. (Become isolated)

Question 11

What happens so that Speciation occurs?

Answer 11

Populations of the same species are isolated from one another. Due to natural selection changes form and this affects reproduction. The two populations are no longer compatible

Question 12

What can keep species isolated from one another?

Answer 12

Geographical Barriers

Biological Barriers

Question 13

How do Geological Barriers isolate species?

Answer 13

Barriers such as mountains and rivers keep species physically separated. It does not have to remain forever only long enough for them to not be reproductively compatible

Question 14

How do biological barriers isolate species?

Answer 14

Behavior can keep species isolated. ex. different species have different mating calls

Question 15

How can Speciation occur in population that aren’t already reproductively isolated populations?

Answer 15

They become reproductively isolated by using different resources

Question 16

What is Adaptive Radiation?

Answer 16

The diversification of a common ancestral species into a variety of species, all of which are differently adapted

Question 17

What are the 2 models that scientist have proposed for the pace of evolution?

Answer 17

Gradualism and Punctuated Eqilibrium

Question 18

What does the model of Gradualism say?

Answer 18

Gradual changes occur steadily in a linear fashion. Big changes are the result of many small changes

Question 19

What does Punctuated Equilibrium say?

Answer 19

Evolutionary history consists of long periods of equilibrium where there is little change interrupted by periods of speciation

Question 20

What are the ideas in the theory of evolution by natural selection?

Answer 20

1. Life forms have developed from ancestral species
2. All living things are related to one another by varying degrees through common descent
3. All living things on earth share a common ancestor
4. The mechanism for speciation includes random genetic mutations and natural selection