Better to say that it’s we and our primate cousins, who’ve *gained* the ability to distinguish colors at the yellow end of the spectrum! After all, there are more mammals with bichromatic vision than there are primates….

The partial form of R/G colorblindness runs in my family. This is on my father’s side, so I’m unaffected, but one of my nephews has it, as did Dad and both his brothers. One interesting point is that people with the condition have *better* detail vision, directly proportional to the degree of colorblindness!