pterosaurs swam, so I guess they managed it without developed hypotarsus and cnemial crest. Thinking about it, those trace fossils tell us a bit about how pterosaurs might have swam, with their hindlimbs paddling in a parasagittal fashion. I'm not sure their forelimbs would be much use in swimming, mind.
why would they neccessarily (need to) use their forelimbs?
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