All humans have the ability to see ultraviolet light, but it is passively filtered out by the eye's lens. People who undergo surgery to remove the lens can detect ultraviolet light.
21
Blue eyes are a genetic mutation. Before the mutation occured, all humans had brown eyes.
89
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217
The average person's skin weighs twice as much as their brain.
131
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
The brain receives 20% of the body’s oxygen and 25% of total body glucose utilization, despite it accounting for only 2% of a person’s weight (about 1.4 kilograms).
8
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99