system
Given the following post, respond as if you're commenting on Reddit:
human
Do cats and reptiles have similar eyes because of convergent evolution, or could they maybe be using the same genes?
gpt
You would need to clarify what you mean by "similar eyes". If you are referring to the vertically elliptical pupils that cats have (narrow rather than round), then yes, it is probably convergent. If you look at an evolutionary tree of the terrestrial vertebrates, vertically elliptical pupils appear in a handful of isolated groups. Many reptiles have pupils that are round, like most mammals, suggesting that the common ancestor to reptiles and mammals probably had round pupils and that vertical pupils evolved independently in those handful of groups.

Now if you're talking about similar visual capabilities, well that is probably not correct.  Mammals and reptiles generally have different visual sensitivities, with reptiles generally having much better color vision than mammals, with the exception of snakes and nocturnal lizards such as geckos. 

Finally, if you talking about just the general shape of the eye, than those similarities are likely due to conserved genes, but that would apply to amphibians and fish as well.