24.4 Speciation can occur rapidly or slowly and can result from changes in few or many genes

Question 1

47) Speciation
A) occurs at such a slow pace that no one has ever observed the emergence of new
species.
B) occurs only by the accumulation of genetic change over vast expanses of time.
C) must begin with the geographic isolation of a small, frontier population.
D) proceeds at a uniform tempo across all taxa.
E) can involve changes involving a single gene.

Answer 1

E) can involve changes involving a single gene.

Question 2

48) Which of the following statements about speciation is correct?
A) The goal of natural selection is speciation.
B) When reunited, two allopatric populations will not interbreed.
C) Natural selection chooses the reproductive barriers for populations.
D) Prezygotic reproductive barriers usually evolve before postzygotic barriers.
E) Speciation is a basis for understanding macroevolution.

Answer 2

E) Speciation is a basis for understanding macroevolution.

Question 3

50) In order for speciation to occur, what is true?
A) The number of chromosomes in the genome must change.
B) Changes to centromere location or chromosome size must occur within the genome.
C) Large numbers of genes that affect a single phenotypic trait must change.
D) Large numbers of genes that affect numerous phenotypic traits must change.
E) At least one gene, affecting at least one phenotypic trait, must change.

Answer 3

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

Question 4

1) The largest unit within which gene flow can readily occur is a A) population.
B) species.
C) genus.
D) hybrid.
E) phylum.

Answer 4

B) species.

Question 5

2) Bird guides once listed the myrtle warbler and Audubonʹs warbler as distinct species. Recently, these birds have been classified as eastern and western forms of a single species, the yellow-rumped warbler. Which of the following pieces of evidence, if true, would be cause for this reclassification?
A) The two forms interbreed often in nature, and their offspring have good survival and reproduction.
B) The two forms live in similar habitats.
C) The two forms have many genes in common.
D) The two forms have similar food requirements.
E) The two forms are very similar in coloration.

Answer 5

B) The two forms live in similar habitats.

Question 6

3) Males of different species of the fruit fly Drosophila that live in the same parts of the Hawaiian islands have different elaborate courtship rituals that involve fighting other males and stylized movements that attract females. What type of reproductive isolation does this represent?
A) habitat isolation
B) temporal isolation
C) behavioral isolation
D) gametic isolation
E) postzygotic barriers

Answer 6

C) behavioral isolation

Question 7

5) Plant species A has a diploid number of 12. Plant species B has a diploid number of 16. A new species, C, arises as an allopolyploid from A and B. The diploid number for species C would probably be
A) 12.
B) 14.
C) 16.
D) 28.
E) 56.

Answer 7

D) 28.