Tigers can see 6 times better at night than humans.
305
Your thumb is about the same size as your nose.
124
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
Babies crawl an average of 200m a day.
212
Pet dogs and elephants are the only animals that seem to instinctively understand human gesture.
14
On average, there's 100 billion neurons in the human brain.
83
Modern humans first appeared about 200,000 years ago, but record keeping didn't begin until about 6,000 years ago. That means about 97% of human history is lost.
21
There are glasses which allow a red-green color-blind person to see colors the way everyone else does.
22