[sharkeyandgeorge]

heres a question i hope you science peeps can help me with. Eyes have both cones and rods and its a defficency in one that leads to colour blindness, yes? so what happens if the other set is damaged can you see colours but not shades or what? maybe I have completely the wrong end of the stick and someone can tell me what actually happens.

J.B.S Haldane on the perforated eardrums which were a consequence of his pressure experiments "the drum generally heals up; and if a hole remains in it, although one is somewhat deaf, one can blow tobacco smoke out of  the ear in question, which is a social accomplishment".

[neilep]

Good question.....I of course have no idea...but would like to add an extra questions too if I may...

..is it right that only males are affected by colour blindness ?....if so...why ?

Thanks for letting me share this thread with you Mr Sharkey & Mr George !

Men are the same as women, just inside out !

[gecko]

ok. heres my completely unsourced knowledge of the subject.

you have 3 "cones" or "rods"... or something... that see basically 3 primary colors. yellow, blue, red. you see greens and purples and such because of all cones working. usually in color blindness only one of the cones is deffective, dulling that cones spectrum of color. very rarely 2 cones are deffective, and even less likely is actual "black and white" vision, when no cones work.

it effects males because it is inherited on the Y chromosome. i forget, but i believe its some sort of double-recessive thing. females are rarely, if ever, effected not having a Y chromosome; and if they are its more likely from a direct eye injury.

[another_someone]

The 3 cones give us colour sight.  The rods give us night vision.  If you lose your rods, you will still see colour, but will have difficulty seeing at low light levels.

I believe that there is also a difference in distribution is cones and rods, with cones being more dense at the centre of your vision, since these are intended for high definition sight when light levels permit, whereas the rods are more evenly distributed, being more used to detect danger on the periphery of your vision during dusk and down, or on a moonlit night.

George

[ROBERT]

" Colour blindness not all it seems  
 
Forms of colour blindness may actually give people enhanced perception of some colours.
Researchers asked people with a form of colour blindness called deuteranomaly - the most common form of the condition - to assess pairs of colours.

The University of Cambridge team found these people were able to distinguish between pairs that looked identical to those with "normal" colour vision.

The study is published in the journal Current Biology."
http://news.bbc.co.uk/2/hi/health/4498734.stm
 

[ROBERT]

" Colour blindness not all it seems  
 
Forms of colour blindness may actually give people enhanced perception of some colours.
Researchers asked people with a form of colour blindness called deuteranomaly - the most common form of the condition - to assess pairs of colours.

The University of Cambridge team found these people were able to distinguish between pairs that looked identical to those with "normal" colour vision.

The study is published in the journal Current Biology."
http://news.bbc.co.uk/2/hi/health/4498734.stm