Vision (eyesight): Do women see colors better than men? If so, why?

The answer surprised me (I had to research this question) but it seems that some women may be able to differentiate colours better than men. http://www.asu.edu/news/research/womencolors_090104.htm.

The color test you have linked is too time consuming. In the past I have done such tests and scored 100%. It is true that men have a higher occurrence of color-blindness than women. It is also highest amongst men as red/green, which is why standard household wiring has been recoded into Blue, Brown, Green/Yellow -- The Blue can be clearly seen, the Green/Yellow may be difficult, but the stripe brightness helps, and the remaining invisible (black?) one is the Brown. I find it interesting that while Red/Green is the most common form of color deficiency with Yellow being a mix of Red and Green, that traffic lights have not introduced a Blue color to aid in distinguishing between stop and go.

What I remember from school is that men's and women's eyes are set up differently. Cones are what allow us to see color. Rods allow us to see shapes. Women, in general, have more cones than men. Men, in general, have more rods than women. This makes sense from an evolutionary standpoint. Women would have dealt more with gathering food like berries. A nice ability to have would be the ability to discern the difference between all the "red" berries. The difference between them could be a meal, or poisoning your family. As such, women who have better color vision live to pass on their genes. Men on the other hand need to quickly tell the shape of whatever is in front of them. Especially in the dark when colors don't help. Men with less rods couldn't discern shapes quickly, and they likely died early. That means men with more rods pass on their genes. But again, that's just what I remember from school. More recent studies point to how our brains process information. Men and women with the same cone setups still perceive colors differently. This isn't fully understood. Although researchers speculate it has to do with our body chemistries. Men having extra testosterone, women having extra estrogen, etc. More research to come I imagine.

Not really an answer to your question, but to explain something about the difference in colour blindness occurring in men and women. The gene that makes it so that you can see color is on the X chromosome. If you can't see all colors that means that you do not have a working version of the gene. Because men only have one x chromosome, they are more likely to be color blind, as they only need 1 defect allele. Women have two X chromosomes, and if they are color blind it means they have two defect alleles. This happens way less often. As far as I know, this has nothing to do with the amount of colors that an average woman can see compared with an average man.

To add to the other answers, we have cones that detect 3 color ranges -  S-cones, M-cones and L-cones, for short-wavelength, medium-wavelength and long-wavelength light. One study suggested that 2–3% of the world's women might have the type  of fourth cone whose sensitivity peak is between the standard red and  green cones, giving, theoretically, a significant increase in color  differentiation.  (Roth, Mark (13 September 2006). http://www.post-gazette.com/pg/06256/721190-114.stm. Pittsburgh Post-Gazette.)

Females are born pre-wired to be interested in faces and males are pre-wired to be interested in moving objects. This leads females to be more relationship focused and males more action focused.This difference is biologically found in the retina of the male and female eye. The retina has two layers, the second of which is made up of P and M cells. M cells are motion detectors and track objects anywhere in the visual field. They answer the question: “Where is it now and where is it going?” M cells compile information about direction and motion. M cells dominate the male retina.P cells focus on the question: “What is it?” They compile data about texture and colour. Female retinas are rich in P cells.(7)This difference in P and M cells gives women an increased ability over men to identify orange as having many shades from pale peach to vibrant coral, while men are likely to identify orange as ‘orange’.Here are some relevant references:“Sex Differences in Human Neonatal Social Perception,” Jennifer Connellan Simon Baron-Cohen and Associates, Infant Behaviour and Development, 2000. “The Dynamics of Primate Retinal Ganglion Cells,” Ehud Kaplan and Ethan Bernardete, Progress in Brain Research, 2001.“Sex-Specific Development Changes in Amygdala Responses to Affective Faces,” William Killgore, Mika Oki, and Deborah Yurgelun-Todd, NeuroReport, 2001. “Gender Differences in Regional Cerebral Activity During Sadness,” Frank Schneider, Ute Habel and Associates, Human Brain Mapping, 2000.

I am curious as to how one can answer this question objectively.  I have no clue how one would compare the "intensity" of their color perception with any other person.