Re:Bananas Are Berries, Strawberries Aren't
by bustadjustme on Monday January 20, 2020 @02:51PM
(#22101608)
.... whales certainly aren't bony fish. They're in class Mammalia, which is not within the superclass Osteichthyes. I.e. they're mammals, not fish.
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Re:Bananas Are Berries, Strawberries Aren't
by robbrown451 on Monday January 20, 2020 @04:21PM
(#22102188)
Mammals are tetrapods, which are indeed under Osteichthyes (unless you consider Ostreichtyes to be paraphyletic).
If you look at the cladogram on the wikipedia page I linked, you see a picture of a salamander near the top representing the category Tetrapodomorpha. We (and whales) are also on that branch. Sharks are outside of that whole cladogram, as they are cartilaginous fish. ( * )
In other words, any clade which includes all bony fish also includes mammals.
[*] which means that the most recent common ancestor of sharks and goldfish lived longer ago than the most recent common ancestor of whales and goldfish