Quiz Chapter 22 pt3

Question 1

Beetle pollinators of a particular plant are attracted to its flowers bright orange color. The beetles not only pollinate the flowers, but they mate while inside of the flowers. A mutant version of the plant with red flowers becomes more common with the passage of time. A particular variant of the beetle prefers the red flowers to the orange flowers. Over time, these two beetle variants diverge from each other to such an extent that interbreeding is no longer possible. What kind of speciation has occurred in this example, and what has driven it?

Answer 1

Sympatric Speciation

Question 2

The most likely explanation for the recent decline in cichlid species diversity in Lake Victoria is

Answer 2

Fusion

Question 3

The origin of a new plant species by hybridization, coupled with accidents during cell division, is an example of

Answer 3

Sympatric Speciation

Question 4

In a hypothetical situation, a certain species of flea feeds only on pronghorn antelopes. In rangelands of the western United States, pronghorns and cattle often associate with one another. If some of these fleas develop a strong preference for cattle blood and mate only with other fleas that prefer cattle blood, then over time which of the should occur, if the host mammal can be considered as the fleas habitat?

Answer 4

1. Reproductive isolattion, sympatic speciation.

4. Habitat isolation, prezygotic barriers.

Question 5

Two species of frogs belonging to the same genus occasionally mate, but the offspring fail to develop and hatch. What is the mechanism for keeping the two frog species separate?

Answer 5

The postzygotic barrier called hybrid inviability.

Question 6

There is still some controversy among biologists about whether Neanderthals should be placed within the same species as modern humans or into a separate species of their own. Most DNA sequence data analyzed so far indicate that there was probably little or no gene flow between Neanderthals and Homo sapiens. Which species concept is most applicable in this example?

Answer 6

Biological

Question 7

Speciation

Answer 7

The formation of new and distinct species in the course of evolution.

Question 8

In order for speciation to occur, what must be true?

Answer 8

At least one gene, affecting at least one phenotypic trait must change.

Question 9

Which of the following statements about Species, as defined by the biological species concept, is (are) correct?

Answer 9

1. Biological species are defined by reproductive isolation

3. The biological species is the largest unit of population in which successful interbreeding is possible.