Can a reptile swim

Contributors have said:

No. None of the dinosaurs flew. The flying reptiles that lived during the Age of Dinosaurs were not dinosaurs.

According to recent fossil finds in China, there were lots of feathered dinosaurs in the late Cretaceous period, but none of them flew -- their bones were just too heavy to have permitted flight. The first reptile that has actually been classified as a bird (since it had flight feathers, a wishbone, etc.) showed up in the Jurassic period, and there are a lot of paleontologists who doubt that it could actually fly (i.e. gain altitude by wing flapping). However, by modern monophyletic standards birds are classified as dinosaurs.

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Yes. And it's a "semantics thing" because the Word dinosaur applies to the critters from that era that lived on the ground and does not include the reptiles that flew. The pterosaurs were related to the dinosaurs, though. It boils down to the usage of the Word dinosaur.

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It is true that pterosaurs were related to dinosaurs, but the relationship was very distant indeed. They were no closer taxonomically to the dinosaurs than the plesiOSaurs, for instance, and those latter were related only in that their anatomy seems to be more reptilian than amphibian or mammalian. The pterosaurs may be even more distant than those aquatic animals since some of their fossils have been found with traces of hair on their bodies rather than feathers.

There were a lot of animals living during the Mesozoic that are mistakenly believed to be dinosaurs, particularly those that moved through 3 dimensional habitats. The Mosasaurs, for instance, are just big Varanid lizards, thus are more closely related to today's monitors of the old world than to the dinosaurs. The Ichthyosaurs have an evolutionary history that is rather perplexing. They may be Sauropsids - a lot of taxonomists think they are - but whether or not they were Diapsids is pretty much up for grabs. Pre-ichthyosaurs (Triassic types) seem like primitive lizards.

Interestingly enough, at least one well-known vertebrate paleontologist of high repute (curator of vertebrate fossils at Carnegie Museum) is of the opinion that the only reptiles that ever existed are those that are alive today. The earlier ones, he insists, are in the Class Amniota and are distinct from those in the Class Reptilia.

The term ''Dinosaur'' has been a catch-all term for more than a century, is a bit over-used, and is rather archaic having been coined by Owen in the 19th century. Since then it's been applied to just about every reptilian organism that lived before the end of the Cretaceous period.

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Technically, birds are classified as dinosaurs, so if you are including birds, yes.