A friend tells you that whales don't have hind limbs b/c they didn't develop them why they descended from fish

Clear up your friend's misconceptions. What intermediate were part of the history of whales from fish (back to) the ocean? Did any of them have hind limbs?

A friend tells you that whales don't have hind limbs b/c they didn't develop them why they descended from fish
the whale actually came from the same common ancestor as the cow and the pig. They do have hind limbs but they are residual limbs, they are no longer seen but the bones are still there. Whales also still have the four chambered stomach (or ruminant stomach) that cows have. The pig is actually the closest living relative to the whale.


At no point in time did the whale descend from any type of fish, they were originally land mammals and moved to the sea later.
Reply:The answerers above me have clearly explained that a whale is NOT a fish. So, what about the other misconceptions? You could show the fossil record of whale evolution. It goes like this; Sinonyx, Pakicetus, Ambulocetus, Rodhocetus, Basilosaurus, Dorudon. From the most ancestral to the most recent species, these fossils show consistent changes that indicate a series of adaptations from more terrestrial to more aquatic environments.





As for hindlimbs, in many embryonic whales, external hind limb buds are visible for a time but then disappear as the whale grows larger. A few species of whales still possess a vestigial pelvis, and some have greatly reduced and nonfunctional hindlimbs. Ambulocetus, listed above, was clearly a cetacean, but it also had functional legs and a skeleton that still allowed some degree of terrestrial walking.
Reply:Whales actually *do* have hind limbs. They have the vestiges of them, anyways. In a whale's skeleton, there are little bones, a lot like leg bones, only (proportionally) miniaturized. They have receded so far into the whale that they are no longer visible on the outside.





And it's more probable that whales descended from land mammals moving back into the water, because they're mammals and all.





:)





Hope this is at least partially answering your question. It was kind of unclear to me.
Reply:Greetings!





First, whales didn't descend from fishes. They are mammals, with mammalian ancestors who probably have taken to the sea for survival. Whales not having hind limbs have no connection with fish at all, it must only be because their ancestors also lack hind limbs, a hypothetical explanation of why they took to the sea.

gardenia