Yes, but neither fish nor (fish union cetaceans) is monphylatic. The decent tree rooted at the last common ancestor of fish also contains tetrapods and decent tree rooted at the last common ancestor of tetrapods contains the cetaceans.
I am not any sort of biologist, so I am unclear on the terminological technicalties, which is why I handwaved this in my post above.
The usual term is “monophyletic”.
Yes, but neither fish nor (fish union cetaceans) is monphylatic. The decent tree rooted at the last common ancestor of fish also contains tetrapods and decent tree rooted at the last common ancestor of tetrapods contains the cetaceans.
I am not any sort of biologist, so I am unclear on the terminological technicalties, which is why I handwaved this in my post above.
Fish are a paraphyletic group.