What are alleles?
Explain

In natural selection, what is actually “selected? ” a) alleles are directly selected b) genotypes are directly selected c) phenotypes are directly selected d) entire populations are directly selected

Melting glaciers is a serious threat to the environment what is the possible consequence of melting glaciers on polar bears?

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.