As Embryos,baleen Whales Have Teeth and Also Have Two Nostrils

question 48

Multiple Choice

As embryos,baleen whales have teeth and also have two nostrils directly above their mouth.Before birth,however,the teeth are reabsorbed,and the nostrils migrate and fuse to become the blowhole.What does this observation suggest about the ancestry of these whales?

• A) Baleen whales descended from an aquatic ancestor that breathed through an elongated snout, much like the modern alligator does today.
• B) Baleen whale ancestors lived in habitats where the potential for mutation was relatively high; early abnormalities during embryonic development are later corrected before birth.
• C) Baleen whales evolved from a terrestrial mammalian ancestor and share common inherited developmental features.
• D) Modern terrestrial mammals are descended from the same marine mammal ancestors that gave rise to modern whales.

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