Activational effect is the correct answer.
Activational effect is an impermanent hormonal effect that leads to a change in physiological activity or behavior in both humans and adult animals. For instance, when testosterone levels rise in male songbirds they become more aggressive and tend to engage in courtship behavior. Also, a pregnant woman may get more emotional than usual due to an extra level of progesterone and estrogen during pregnancy.
Hello!
Natural selection is the way that animals evolve.
The theory of natural selection is that the animals that do not have a specific trait to survive in their environment will die. The animals that do have the trait will survive. The animals that survive will then pass the trait down to their offspring, who will also likely survive because they have the trait. This is how species evolve and continue to survive in their environment.
The species evolve because only the fittest survive (this is known as "survival of the fittest"). The animals that do not have the needed traits will die and they cannot have offspring.
I hope this helps answer your question! Have a great day!
Bacteriaciltous is what I'd try to learn I love the complexity