Why do we call Paleozoic chondrichthyans such as Cladoselache "sharks," and why isn't that terminology strictly correct?
What will be an ideal response?
Cladoselache looks rather like a shark without an underslung mouth: like many other fishes (including most sharks) it has a torpedo-shaped, streamlined body and it probably had a lifestyle that was similar to that of modern sharks. Those factors make it convenient to refer to Cladoselache as a shark. Strictly speaking, however, the term "shark" should be reserved for the neoselachian sharks that are around today,
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