Scientists look at thousands of mutagenized flies, one at a time, under a microscope. they are looking for flies that don't look like they have developed normally. they find a remarkable fly with an extra thorax and a complete extra set of wings. this is an example of

Why is it important to reduce the number of chromosomes in half when forming gametes for sexual reproduction?

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.

What type of competition exsist between two species. turtles and fish