Answer:
The average trait value changed in one direction.(In this case, larger size)
Explanation:
In evolution a natural selection can be disruptive, directional or stabilizing
In stabilizing no extreme trait is favored hence provides intermediate values .
Disruptive selection both extreme traits are favored over the intermediate trait.
Directional, the enviroment will favor the survival of one trait hence a change in direction either towards the left or the right.
In the case of swallow cliff mortality, selection favored the larger size.
Answer:
D. predator population will decrease
Explanation:
If the population of prey species decreases then the competition between the predator population will increase and natural selection will act on them. So nature will select those individuals among predators who are more fit and adapted and less fit individuals will die.
So a few year after the predator population will decrease as there are not enough prey to support the large population of predators which was present when prey were abundant. Therefore the correct answer is D.
Answer - C
Snakes periodically shed their skin in order to regrow new skin. Birds migrating to the south and bears hibernating are also a result of normal periodic transitions. However, extinction of a type of shrimp is most likely a result of a drastic change in the environment.
