Yawns are more contagious among people with closer relationships.
163
The human brain doesn't stop developing until about 25 years old.
102
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149
When you take a step, you are using up to 200 muscles.
886
Your thumb is about the same size as your nose.
124
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13