The oldest stone tools found are dated from 2.7 - 2.9 million years ago. The species that made these tools is unknown.
13
A man's beard grows fastest when he anticipates sex.
239
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
The human eye blinks an average of 4,200,000 times a year.
233
Yawns are more contagious among people with closer relationships.
163
It takes about 20 seconds for a red blood cell to circle the whole body.
102
Obsessive nose picking is called Rhinotillexomania.
101