Why do almost all vertebrates have tails, but not apes and frogs?

Last Updated: 02.07.2025 17:55

Why do almost all vertebrates have tails, but not apes and frogs?

And apes and frogs are no exception. Both still have the lost anal tail. It is just shortened and entirely hidden inside the adult body. But you can still see it in their skeletons.

Vertebrates are chordates and all chordates have, as part of the defining body plan of the phylum, a post anal tail.

And of course, frogs have a perfectly normal and prominent chordate post-anal tail as juveniles.

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