Which is the right answer?

Asquirrel population lives in an area. over many years, a river in that area grows wider and stronger, eventually forming a canyon. the squirrel populations on the two sides of the canyon can no longer mate with each other and ultimately form distinct species. this is an example of

What are the three groups of atoms that make up amino acids called

Achemical that is released by an animal as a signal to other members of the same species is called a pheromone. t or f