You are at the aquarium looking at a freshwater mammal tank and a manatee swims close to the glass. On his front flippers you see fingernails. You think, what possible use could fingernails be to a manatee, then you realize they are of no use at all. Which of the following best explains the presence of fingernails on a manatee?
A. they are remnants of the bones used by fish for their fins.
B. they are homologous structures.
C. the bones are protruding from the fins and only look like fingernails, even though every manatee in the tank looks like it has fingernails.
D. convergent evolution has occurred.
E. they are vestigial structures.
E. they are vestigial structures.
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Answer the following statement true (T) or false (F)
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