Chapter 18 part 2 study set

What is the main difference between dispersal and vicariance? A: One involves the movement of the organism, and the other involves a change in the environment. B: One depends on a genetic mutation occurring, and the other does not. C: One involves closely related organisms, and the other involves only individuals of the same species. D: One leads to allopatric speciation, whereas the other leads to sympatric speciation.

A: One involves the movement of the organism, and the other involves a change in the environment.

In the process of adaptive radiation, there is usually one species from which others will quickly diverge. This original species is known as the A: founder species. B: original isolate. C: primary progenitor. D: radiating organism.

A: founder species.

Which variable increases the likelihood of allopatric speciation taking place more quickly? A: longer distance between divided groups B: lower rate of mutation C: increased instances of hybrid formation D: equivalent numbers of individuals in each population

A: longer distance between divided groups

What is the convergence of two closely related species over time? A: Reinforcement B: Fusion C: Stability D: Gradual speciation

B: Fusion

Some animals are referred to as "living fossils" because they have had a nearly unchanged appearance for tens or hundreds of millions of years. What does this suggest about these species? A: They have a long generation time. B: They are well-adapted to a stable environment. C: They are herbivores. D: Their DNA is less vulnerable to mutation.

B: They are well-adapted to a stable environment.

Within a hybrid zone, reinforcement occurs if hybrids are: A: more fit than the parents. B: less fit than the parents. C: able to reproduce faster than the parents.

B: less fit than the parents.

Which components of speciation would be least likely to be a part of punctuated equilibrium? A: a division of populations B: ongoing gene flow among all individuals C: a change in environmental conditions D: a large number of mutations taking place at once

B: ongoing gene flow among all individuals

Which term is used to describe the continued divergence of species based on the low fitness of hybrid offspring? A: fusion B: reinforcement C: stability D: punctuated equilibrium

B: reinforcement

Once two species develop through speciation, they cannot fuse into a single species again. A: True B: False

B:False

A group of mice become separated from their original population when engineers change the path of a river. If speciation occurs, this would be an example of A: Sympatric speciation. B: Dispersal. C: Vicariance.

C: Vicariance.

Which situation would most likely lead to allopatric speciation? A: A storm causes several large trees to fall down. B: An injury causes an organism to seek out a new food source. C: flood causes the formation of a new lake. D: A mutation causes a new trait to develop.

C: flood causes the formation of a new lake.

Punctuated equilibrium describes new species branching quickly and then A: branching more quickly over the subsequent generations. B: fuse back together slowly over many generations. C: quickly go extinct to allow for adaptive radiations. D: remain stable over long periods of time.

D: remain stable over long periods of time.