When you are looking at someone you love, your pupils dilate, they do the same when you are looking at someone you hate.
1k
The average sperm cell swims at 8 inches per hour.
4
Poor eyesight (myopia) is associated with higher IQ.
232
Tigers can see 6 times better at night than humans.
305
There are glasses which allow a red-green color-blind person to see colors the way everyone else does.
22
Pain occurs when sounds are above 130 db.
124
It is possible for you to survive even after the removal of the spleen, the stomach, one kidney, one lung, 75% of the liver, 80% of the intestines, and almost every organ from the pelvic and groin area.
218
The human brain uses approximately as much energy as a 10 watt light bulb.
120