When you kiss someone for the first time, you get a spike in the neurotransmitter dopamine, making you crave more.
23
By weight, Bone is five times stronger than steel.
417
If your DNA was stretched out it would reach to the moon 6,000 times.
256
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
Humans are capable of running 40 mph according to a study by bio-mechanical expert Dr. Matthew Bundle. Today's fastest man, Usain Bolt, has a top speed of 28 mph.
35
On average, a human being will have sex more than 3,000 times and spend two weeks kissing in their lifetime.
161
The average sperm cell swims at 8 inches per hour.
4
A person will create enough saliva to fill two average size swimming pools during his lifetime.
191