More males than females are colorblind. In fact, if you know 12 males, odds are that at least one of them has some degree of color blindness. This condition occurs when the cones (or special cells) in a person's retina do not work properly. Although they can see most colors, they may have trouble distinguishing red from green, or other colors may appear gray. You can do a science fair project to see whether color blindness is genetic.
Find an online color blindness test that you can use for this project. Take a look at the Resources section for ideas.
Print out the color blindness tests that you chose on a high-quality color printer. Make sure that the resulting printout looks as similar as possible to the online version of the picture.
Sciencing Video Vault
Administer the color blindness test to at least 50 people. Take data, making sure to note whether the subject seems to be colorblind based on the results.
Encourage your initial subjects to administer the color blindness test to two blood relatives--preferably parents or siblings. (Your results would be even more believable if you administered the tests yourself, but this may be impractical.) Have them write down the results and bring them to you.
Calculate the percentage of your colorblind initial subjects who have at least one relative with color blindness. You can do this by counting the number of colorblind initial subjects who fit this criterion and then dividing it by the total number of colorblind initial subjects.
Calculate the percentage of your non-colorblind initial subjects who have at least one relative with color blindness. You can do this by counting the number of non-colorblind initial subjects who fit this criterion and then dividing it by the total number of non-colorblind initial subjects.
Compare the two results to see whether color blindness seems to have a genetic component.
You may want to ask permission from several teachers to administer your colorblind test to their students. This can also help to ensure that you will receive data from all of your subjects because the teacher can require all students to return the data the next day. If you do not have access to a high-quality color printer, you can administer the test by showing your subjects online pictures. Your subjects, however, will have to have Internet access at home to administer the test to their relatives.