Question

The body sizes of sympatric and allopatric P. cinereus and P. hoffmani are consistent with a hypothesis of character displacement resulting from interspecific competition. What additional information would strengthen the argument that character displacement is in fact responsible for body size evolution in these salamanders? Which of the following observations would support the hypothesis that Plethodon salamanders did indeed experience character displacement for body size? Select all that apply. A. Body size is a heritable trait in salamanders. B. In sympatric populations, smaller P. cinereus adults survive better and reproduce more. C. The sympatric salamander populations evolved their present body sizes after they became sympatric. D. Salamanders that are closer in body size compete less strongly for food. E. The resources used by both species of salamanders are available in limited supply.

Answer 1

Answer:

Option C - The sympatric salamander populations evolved their present body sizes after they became sympatric.

Explanation:

First, note the definitions of each terms.

1) Sympatric occurs when organisms especially of same species occurring in the same, or in overlapping territory, do not interbreed.

2) Allopatric occurs when organisms are NOT living in the same territory and thus unable to crossbreed.

On 1st QUESTION

The argument would be strengthened by the failure of P. cinereus and P. hoffmani to crossbreed making traits for body size to become distinct (dissimilar) in each specie.

On 2nd QUESTION

Definitely, salamanders species occurring in the territory, do not interbreed after they became sympatric, thus, making characters among same species to be increasingly different over generations.