Answer:
by competitionfor food,air,water
The air pollution makes the caribou unhealthy, and this makes them more vulnerable to predators and diseases.
Specifically, the food the caribou digest (for example lichens) absorb the pollution dispoportionally, which means that the caribou ingest many unhealthy particles.
True, this means Johnny is a morning person, after getting a good night sleep he is able to study because he feels more energetic. One always needs a good amount of energy in other to study efficiently and effectively.
I do not know exactly what answer you are looking for here considering the fact that there are many differences between the actions of animals and humans. The best answer I would give is that people have a sense of what is wrong and right and decide based on a moral subconscious. Animals act on they need to survive and do not care about acting civilized or what is right and wrong.
