Following a major change in the ecosystem, what factor will help an ecosystem most likely to survive?

Marianne is comparing two animals: a fruit fly and a fruit bat. she asks, "do a fruit fly and a fruit bat share a common ancestor in their evolutionary history? " according to evolutionary theory, what is the answer to marianne's question?

Why do carbohydrate molecules function so well as fuel for the body?

Several billion years ago which gas was the least prevailant in the atmosphere