During a severe windstorm on an isolated island, some pollen and seeds from conifers are carried high into the air in a cloud of dust. In which of these situations would the dust cloud containing the seeds and pollen be considered an agent for gene flow? А. The dust cloud is subjected to an extended period of ultraviolet radiation, causing a mutation in a gene of
the conifer seeds.

B. The dust cloud settles, and a few of the conifer seeds return to the same environment.

C. The dust cloud is subjected to electromagnetic radiation from the sun, causing the pollen to be unable to
pollinate flowers.

D. The dust cloud settles over a forest on a distant, isolated island and pollinates some conifer trees in that forest

Examine the two squirrel populations in the accompanying figure. the populations are separated by a geographic barrier. if after a long period of time the two species are no longer separated, what evidence is needed to determine if speciation has occurred? the figure shows two populations of squirrels separated by a geographic barrier. examine the two squirrel populations in the accompanying figure. the populations are separated by a geographic barrier. if after a long period of time the two species are no longer separated, what evidence is needed to determine if speciation has occurred? the figure shows two populations of squirrels separated by a geographic barrier. polyploidy is creating new species. the two populations are not interbreeding freely. hybrid offspring of the two populations begin to appear. one species will increase into a population size twice as large as the other species.