They are better adapted to the environment. Their darker color helps them blend in with the tree bark so common in their habitat. Because of that, more are likely to not get eaten by predators than white ones that are so easy to spot without camouflage abilities. The black moths are simply more fit to survive, and more of them will survive in this place.
The answers are DNA and Nucleus
Olivia could exercise more & increase her metabolic rate. Katie can eat more because her body burns calories faster, which causes her to not gain weight. metabolic rate is the rate which metabolism occurs in a living thing :)
It would have a decrease in the numbers of animals because the food chain would be thrown off
