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> Date: Wed, 12 Jun 2002 18:41:36 -0400
> From: Andy Canivet <cathode_ray00@...>
>
> People with only one cone type are extremely rare, but they exist. I
> imagine if there are people with four cones, there must be very few of them
> - but since a "tetrachromat" would suffer no impairment in colour perception
> (quite the opposite), he or she would probably be unlikely to report
> anything about it to a doctor and thus be "discovered." It would really
> only stand out in art class or in discussions of colour naming ;