Question

WILL MARK BRAINLIEST PLEASE HELP

Answer 1

The populations became so different that they cannot interbreed to produce fertile offspring.

This stage is known as reproductive isolation and happens after a species has adapted to it's new surroundings, just like the squirrels adapted to the new canyon.

I hope this helps! I'm happy to answer any other questions you might have :)

Answer 2

Answer:

The populations become adapted to different environments but will still be able to interbreed, but the offspring will not be fertile.

Explanation:

Each squirrel population evolved differently. This has resulted in two genetically different species that inhabit one on each side of the canyon. As the species are genetically different, the cross between them would result from hybrid animals.

Hybrid animals are those born from the cross between two beings of the same species, which are genetically different. Hybrids are known to be sterile animals, ie unable to generate offspring.

For this reason, we can say that in the case of the squirrels shown in the question above, the populations have adapted to different environments, but may still cross because they are of the same species, but the offspring will not be fertile, because the parents are genetically different.