A comparison of the embryonic eye in cavefish and lakefish revealed that both reach approximately 4 mm in diameter. However, lakefish eyes continue to grow, while cavefish eye size is greatly reduced. Speculate on the role of the genes involved in this problem.

Video transcript

Hello, everyone and welcome to today's video. So Hot Wilkins researched blind cay fish in 1988 comparing them to individuals of a sibling species located in a lake with normal eyesight. The species with normal vision were named lake fish speculate on the role of the genes involved in this difference. So as answer choice, A we have lake fish genes inhibit eye growth. What K fish genes promoted as answer choice B we have lake fish genes promote eye growth while KFI genes inhibited as answer choice C, we have both cay fish and lake fish genes promote eye growth. But lake fish genes are more effective as answer choice. D we have both KFI and lake fish genes inhibit eye growth but cay fish genes are more effective. Well, all we have to do to solve this problem really is to look at the phenotype that both the cay fish and the lake fish are going to have. So we're told that the lake fish who are living on a lake have normal eyesight, therefore, their genes must be promoting eye growth. On the other hand, we are told that these cay fish are blind. So they must have genes that are inhibited eye growth. Now, looking at our answer choices, we know now that answer choice B is correct. Lake fish genes promote eye growth. That is why they can see wall cay fish genes inhibited. That is why they're blind. That is our final answer to our question. I really hope this video helped you.