Question 1

Which of the following best describes the Biological Species Concept as proposed by Ernst Mayr?

Accepted Answer

A group of interbreeding individuals that are reproductively isolated from other such groups.

Question 2

Which scenario illustrates a drawback of the morphological species concept?

Accepted Answer

Two frogs of the same species look very different due to color variation.

Question 3

Which of the following is an example of ecological (spatial) isolation?

Accepted Answer

Two squirrel species are separated by a geographic barrier and never meet.

Question 4

A mule is produced from a cross between a horse and a donkey. Which postzygotic isolating mechanism does this illustrate?

Accepted Answer

Hybrid sterility

Question 5

Which of the following is NOT a prezygotic isolating mechanism?

Accepted Answer

Hybrid inviability

Question 6

Which species concept would be most useful for identifying bacterial species?

Accepted Answer

Ecological species concept

Question 7

Which of the following best explains why the biological species concept cannot be applied to extinct organisms?

Accepted Answer

Extinct organisms cannot be observed for interbreeding in nature.

Question 8

Which mechanism prevents gene pools from mixing before zygote formation?

Accepted Answer

Prezygotic isolating mechanisms

Question 9

A population of birds develops a new mating song that is not recognized by other populations. What type of reproductive isolation is this?

Accepted Answer

Behavioural isolation

Question 10

Which of the following is a consequence of genetic changes as a species adapts to its environment?

Accepted Answer

Reproductive isolating mechanisms

Question 11

Which of the following is a plausible reason why two closely related frog species might not interbreed, even if they live in the same area?

Accepted Answer

They have different mating calls.

Question 12

Which of the following best describes hybrid breakdown?

Accepted Answer

Hybrid offspring are viable and fertile, but subsequent generations become inviable.

Question 13

Which of the following would be considered a species under the biological species concept?

Accepted Answer

A group of spiders that look different but can interbreed.

Question 14

Which of the following is an example of gametic isolation?

Accepted Answer

Pollen from one plant species cannot fertilize the ovules of another species.

Question 15

Which of the following is a limitation of using molecular traits to identify species?

Accepted Answer

It may be difficult to draw the line when separating groups.

Question 16

If two populations of crickets reproduce at different times of the year, which type of isolation is this?

Accepted Answer

Temporal isolation

Question 17

Which of the following is a real-world example of mechanical isolation?

Accepted Answer

Two snail species with different shell shapes cannot mate.

Question 18

Which of the following is a characteristic used in the morphological species concept?

Accepted Answer

Measurable traits that distinguish individuals from other species.

Question 19

Which of the following is a plausible outcome when two different species produce an interspecies hybrid?

Accepted Answer

The hybrid is usually sterile or has reduced fitness.

Question 20

Which of the following is a major theme in the study of macroevolution?

Accepted Answer

Speciation and the identification of species.

Origin of Species and Macroevolution: Speciation and Reproductive Isolation

Study Guide - Practice Questions