It was kind of a dick move to create animals that require air, then confine them to the freaking ocean
If you are talking about dolphins they used to be wolf like creatures that due to scarcity of food they had to hunt in water so they slowly evolved into water mammals, dolphins still have claw bones but they are unnecessary and dolphins will get rid of them with time and will develop abilities to breath under water
(This also partially applies to whales)
They were what now?
Mother Nature, come out here I just want to talk
Whales are actually Ungulates, more so hippos, entelodons, etc…
Meaning they were somewhat related to big celebrities such as Daedon (the “hell pig”) and Andrewsarchus.
The appearence of the first ancestors of whales probably looked like a small hoofed thing called Indohyus.
(Illustration by julio lacerda)
(illustration by Tiffany Turill)
Basically they went from tiny hoofed herbivore to bigger hoofed carnivore to crocodile-like thing to seal-like things to big sea predators.