Yawns are more contagious among people with closer relationships.
163
A human brain produces as many as 12,000 to 50,000 thoughts per day, depending on how deep a thinker a person is.
23
Blue eyes are a genetic mutation. Before the mutation occured, all humans had brown eyes.
89
On average a woman has 4 sexual partners in her lifetime.
-143
The human brain doesn't stop developing until about 25 years old.
102
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
When you kiss someone for the first time, you get a spike in the neurotransmitter dopamine, making you crave more.
23