Only 12,000 years ago there was a species closely related to modern humans called Homo floresiensis that had been living on an Indonesian Island. They used fire and rather advanced tools, yet were only about 3 feet tall and weighed around 25kg.
15
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
It took 200,000 years for humans to reach 3 billion in number. It took 40 years for the next 3 billion.
11
Unconsciousness will occur after 8-10 seconds after loss of blood supply to the brain.
93
Tigers can see 6 times better at night than humans.
305
The average person's skin weighs twice as much as their brain.
131
The human brain uses approximately as much energy as a 10 watt light bulb.
120
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266