a. Evolution occurs when there are changes in the frequencies of alleles within a population of interbreeding organisms; for example, the allele for black color in a population of moths becoming more common. So if the resources of a forest are breaking up, and group of a species of plant or animal is naturally selected by the environment, and those surviving species interbreed and evolution would be affected that way. Small horned moose might be naturally selected over small horned moose. A worm that survives in warm soil might be naturally selected over a worm that survives in cold soil.
imagine it would have less effect on a moose. Moose can move over
considerable distances, so populations in different small forests would
be able to interbreed.
Worms don't move as far and so are dependent on many smaller sub-populations interbreeding, like a chain. If the chain is broken, they will have trouble simply "jumping over" that hole, since they simply don't move that far.
I.e. let's say two forested areas (and their populations) are separated by a mile of inhospitable, barren land. A moose can walk a mile easily, but a worm is unlikely to crawl that far. So, this zone creates a barrier for the worm, but not for the moose.
rate me 5 star.....................ok i do
When organisms become isolated the two groups are also not able to reproduce together, so variations and mutations that occur in one group are not necessarily found in the other group. The longer the groups are isolated, the more different they are. They eventually become different species. Moreover, if there is a change in the environment of one group it does not necessarily occur in the environment of the other. So they will evolve and adapt differently.
The finches and other organisms that Darwin found on the Galapagos Islands are examples that demonstrate the effect that environmental change and isolation can have on a species.
i hope now it wil be easy for you................
Content will be erased after question is completed.