Optical illusions occur when what the eyes see conflicts with what the brain expects.
75
The human eye blinks an average of 4,200,000 times a year.
233
Only about 2% of the world population has green eyes.
36
When you are looking at someone you love, your pupils dilate, they do the same when you are looking at someone you hate.
1k
The focusing muscles of the eyes move around 100,000 times a day. To give your leg muscles the same workout, you would need to walk 80km (50 miles) every day.
21
Those things you see in your eyes when you stare into space are called Mouches Voltanes, which are also broadly referenced to as Floaters.
9
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266