The retina; I may be wrong.
Pseudostratified columnar respiratory epithelium
Blood flows to the brain through the internal carotid and vertebral arteries and away from the brain through the internal jugular vein. The internal carotid artery supplies the brain, while the external carotid nourishes other portions of the head, such as the face, skull, scalp and the meninges. The vertebral arteries provide supply to the upper spinal cord, brainstem, cerebellum, and the posterior part of the brain.
Answer:
It depends on the fish (I do not see any pictures) Any fish is an example of natural selection.
Explanation:
A good example would be that polar bears grew and evolved to have white fur to blend in the snow to sneak upon prey. However, their brown bear counterparts failed to do that. So due to better camouflage and hunting technique, the polar bears survived more up north.
