Limbs

Because it's not so easy to gain or lose limbs. Even aquatic mammals which seem to have no limbs, have still rudimentary legs. In other words, it is easier to change something than to gain or lose it.

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Interesting question. I don't have a complete answer, but my guess would be either 1) extra limbs are no great advantage and cost energy or, 2) contingency (that is, things just happened to fall out that way). Gould is famous for having said that if we could "rewind ...

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Interesting question. I don't have a complete answer, but my guess would be either 1) extra limbs are no great advantage and cost energy or, 2) contingency (that is, things just happened to fall out that way). Gould is famous for having said that if we could "rewind ...

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I've been wondering, what does limit the number of limbs?. For example, nearly all vertebrates are cuadrupedal or have vestigial limbs that add up to 4 limbs, why is it that there are no, let's say, hexapedal ( it would be possible for a, let's say, ...

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... severe adverse thalidomide birth defects including serious malformations and limb deformities. Types of birth defects caused by include: Missing limbs Phocomelia – Absence of majority of arm, with hand extending from shoulder Aplasia – Absence of thumb and bone in lower arm Lower extremity limb ...

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