Super interesting. My notes as a colorblind man (might be misunderstanding some stuff though):
(Being a little sloppy with sex stuff here. Not all women have two x’s, women can be colorblind too, etc.)
• Two of our usually-three cones are specified on the X chromosome
• When one of a woman’s X’s specifies an anomalous cone she ends up with a 4th, anomalous type of cone.
• This happens ~14% of the time for women.
• That’s about the same percent as color blindness in men.
• That’s not a coincidence. Because color blindness comes from one of these women’s sons getting that anomalous 4th come instead of a typical 3rd cone. This anomalous cone tends to overlap more with one of the other cones in its range of perceived frequencies, which is what causes color blindness.
• But only a small percentage (not sure what percent yet?) of these women with 4 different cones actually seem to be able to perceive more colors
• that’s because the 4th, anomalous cone might basically fully overlap with one of the typical ones in its perceived frequency range, so it doesn’t really give the brain any additional info
• one question I have: so it seems like not all these anomalous cones are the same. Is there a fixed number of types? Or is it more of a spectrum? Further, are /all/ cones on a variable spectrum? Or is almost everyone’s blue cone exactly the same?
• this was interesting: colorblind men actually have a set of colors they can distinguish that people with normal color vision can’t (the article explains why)
• in this study they found colorblind men (but by looking at unusual things they /could/ see, not things they couldn’t? Not sure) and then tested their mothers to see if they could see extra colors.
• Most of them couldn’t. One of them could. The study was only like 9 people? Safe to say /all/ of these women had 4 types of cones, even though only one of them had a sufficiently non-overlapping fourth one to get some benefit?
• As a colorblind man, I’ve never noticed an ability to distinguish colors others can’t. Only the opposite.
• it’s intellectually neat to know that’s possible, even if it doesn’t tend to “come up” in everyday life.
• It souuuunnndssss like the amount of extra color vision that these tetrachromats get is only the same as the extra color vision /I/ get—that same “theoretically there, but doesn’t seem to come up in everyday life” thing. That’s a little disappointing—I though tetrachromacy was more kooky.
(Being a little sloppy with sex stuff here. Not all women have two x’s, women can be colorblind too, etc.)
• Two of our usually-three cones are specified on the X chromosome
• When one of a woman’s X’s specifies an anomalous cone she ends up with a 4th, anomalous type of cone.
• This happens ~14% of the time for women.
• That’s about the same percent as color blindness in men.
• That’s not a coincidence. Because color blindness comes from one of these women’s sons getting that anomalous 4th come instead of a typical 3rd cone. This anomalous cone tends to overlap more with one of the other cones in its range of perceived frequencies, which is what causes color blindness.
• But only a small percentage (not sure what percent yet?) of these women with 4 different cones actually seem to be able to perceive more colors
• that’s because the 4th, anomalous cone might basically fully overlap with one of the typical ones in its perceived frequency range, so it doesn’t really give the brain any additional info
• one question I have: so it seems like not all these anomalous cones are the same. Is there a fixed number of types? Or is it more of a spectrum? Further, are /all/ cones on a variable spectrum? Or is almost everyone’s blue cone exactly the same?
• this was interesting: colorblind men actually have a set of colors they can distinguish that people with normal color vision can’t (the article explains why)
• in this study they found colorblind men (but by looking at unusual things they /could/ see, not things they couldn’t? Not sure) and then tested their mothers to see if they could see extra colors.
• Most of them couldn’t. One of them could. The study was only like 9 people? Safe to say /all/ of these women had 4 types of cones, even though only one of them had a sufficiently non-overlapping fourth one to get some benefit?
• As a colorblind man, I’ve never noticed an ability to distinguish colors others can’t. Only the opposite.
• it’s intellectually neat to know that’s possible, even if it doesn’t tend to “come up” in everyday life.
• It souuuunnndssss like the amount of extra color vision that these tetrachromats get is only the same as the extra color vision /I/ get—that same “theoretically there, but doesn’t seem to come up in everyday life” thing. That’s a little disappointing—I though tetrachromacy was more kooky.