Other than humans, what is the only primate capable of having blue eyes?

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Black Lemur

Although it’s common to see light eyes in animals such as dogs, cats or even parrots, most of them have brown or dark eyes (irises). Among primates, which include humans, monkeys, apes and other species there is only one exception to blue eyes other than humans, black lemurs.

The blue eyes of humans and lemurs are caused by a single nucleotide polymorphism. In simple terms, ‘blue’ is caused by a single spot in the genes that changed.

The same spot mutated separately in humans and lemurs – something called convergent evolution.