They are mostly made out of protein fiber.
They became adapted to their new environment and became new species which then were not able to produce fertile offspring.
I think its false because gas exchange can happen in blood also
Answer:
As population size approaches the carrying capacity of the environment, the intensity of density-dependent factors increases. For example, competition for resources, predation, and rates of infection increase with population density and can eventually limit population size.
Explanation:
Hope this helps! ^_^