Adaptive Radiation

Question 1

Anagenesis

Answer 1

change from one species into an entirely different species

Question 2

cladogenesis

Answer 2

species develops branching off from the original species, original species remains

Question 3

Adaptive radiation

Answer 3

evolution of ecological and phenotypic diversity within a rapidly multiplying lineage- differentiation of a single ancestor into an array of species (one species to many)

Question 4

Ecological opertunity

Answer 4

the invasion of unused ecological niches leads to rapid diversification

Question 5

Key innovation

Answer 5

the acquisition of a novel adaptive trait that allows organisms to exploit previously unavailable niches

Question 6

Ecological hypothesis

Answer 6

The massive worldwide vegetational shift to angiosperm dominance can be explained by positive feedbacks between angiosperms and their environment

Question 7

The Slow seeding hypothesis

Answer 7

Because of slow growth rates because of inefficient transport systems and low leaf photosynthetic capacity, gymnosperm seedlings are weak competitors with angiosperms in productive habitats -> angiosperms did better

Question 8

Biotic drive for adaptive radiation

Answer 8

coevolution can drive increased rates of evolutionary change- existence of genetic variation and each species as a selective force on the other

Question 9

Escape and radiate hypothesis

Answer 9

organisms under constraint from other organisms will develop new defenses which allow them to escape constraints- evolutionary arms race

Question 10

Positive reinforcement

Answer 10

they go back and forth, one adapts, the other adapts in response