eyeless cave fish are still cave fish (of the genus astyanax). The cave fish with eyes and the cave fish without are both of the same order of genus still. wikipedia states that they the same genus and even same species....."The eyed and eyeless forms of A. mexicanus, being members of the same species, are closely related and can interbreed. " They didn't change genre or kind at all. So this is not true evolution (on a macro scale.) It's just micro evolution, like getting over the flu virus. That happens all the time. I have a permanent change in my blood type. I had hepatitis A and can no longer donate blood at a blood bank. But I am still human because my body went through micro evolution. But true macro evolution still is un observed; and monkeys don't become humans (macro evolution) because they are different genre and different kinds of vertebrates. finally, even though species may evolve blindness they do not evolve eye sight (or the complete eye.) This is irreducibly complex and cannot evolve (similar to bacterial flagellum). Those are claims amongst evolutionists that are speculation and in dire need of evidence.
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