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
Having sex can make a woman look younger and more attractive due to the release of estrogen and collagen.
346
A person will create enough saliva to fill two average size swimming pools during his lifetime.
191
A human being loses an average of 40 to 100 strands of hair a day.
133
Babies crawl an average of 200m a day.
212
Tigers can see 6 times better at night than humans.
305
Our brains have a negativity bias and will remember bad memories more than good ones.
15