It took 200,000 years for humans to reach 3 billion in number. It took 40 years for the next 3 billion.
11
The average person's skin weighs twice as much as their brain.
131
Playing Tetris after a traumatic event can prevent the development of traumatic memories and reduce the chance of having flashbacks.
29
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
On average, there's 100 billion neurons in the human brain.
83
There are glasses which allow a red-green color-blind person to see colors the way everyone else does.
22
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 human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13