2. The human eye is amazingly receptive and precise, too. How sensitive are our eyes? If the Earth was flat, you could spot a candle flickering at night up to 30 miles away!
3. There are so many countless thousands of bacteria inside your stomach and digestive system, that they could form an ecosystem the size of a rainforest by themselves.
4. Why is love still the strongest human emotion? When you fall in love, your brain emits the same mix of neurotransmitters and hormones that are present when you take amphetamines, leading to increased heart rate, intense feelings of excitement, euphoria, and loss of appetite and sleep.
5. Human beings have evolved so far, right? Well, we still have the same amount of hairs on our bodies as the average chimpanzee, though most are so fine they can’t be seen.
6. Your eyes focus so often, that the muscles enabling them to perform that function have to move around 100,000 times a day. To put that in perspective, to put your leg muscles through the same workout, you’d have to walk about 50 miles in one day.
7. Every time you gain a pound of fat or muscle, your body grows the equivalent of seven miles of new blood vessels.
8. How much blood do you pump through your body? In one day your blood travels a total distance of about 12,000 miles just within your body, or the equivalent of four times across the United States coast-to-coast.
9. Scientists have made a startling discovery – that the connected neurons in our brains look incredibly similar to the structure of the universe.
10. While we are mostly taught that we have five senses, sound, sight, touch, smell and taste, human beings actually possess 15 additional senses, including balance, temperature, pain, time as well as internal senses for suffocation, thirst, and fullness.
11. It’s a fact that women see colors better than men. But some women have four or even five color receptors when the average person only has three, allowing them to see a wider range on the spectrum.
12. A strange condition called “Synethesia” causes senses to overlap, which means some people can actually hear colors or taste words. Though not enviable, the possibilities are incredible: “Imagine that when you see a city's skyline, you taste blackberries. Or maybe when you hear a violin, you feel a tickle on your left knee. Perhaps you are completely convinced that Wednesdays are light red.”
13. The necessity to breathe is the most primal of human urges, but did you know that it has more to do with our need to expel carbon dioxide from the blood and less than our oxygen supply? In fact, if it weren’t for that carbon dioxide discharge, we’d only have to take a breathe about once every minute.
14. Why do people feel better after a good cry? Scientists have proven that crying actually decreases levels of stress, anger and sadness.
15. 1We know that Westerners eat a lot – but that’s a TON! Literally - most westerners eat more than 50 tons of food over the course of their lifetime.
6. Each one of our kidneys hold about one million filters that can clean out about 1.3 liters of blood every minute.
17. Each person has about half-a-million sweat glands that can produce a full pint of sweat in one (hot) day!
18. Human beings are so visual that 90% of the information we gather and perceive from our environment is from our eyesight.
19. Many people don’t realize that the skin is the largest organ in the human body, covering about 20 square feet if it was stretched out.
20. For us to taste something, our saliva needs to dissolve it. If you don’t believe me, dry off the tip of your tongue and then dab a bit of food on it.
21. A single drop of our blood contains about 10,000 while blood cells and 250,000 platelets.
22. Have you ever seen a dog with different color eyes? That condition is called Heterochromia, and occurs in human beings as well, although it’s rare. (Actor Kiefer Sutherland has Heterochromia.)
23. Are you smarter than a six year old? Probably, but by the time you’re six, your brain is already 90 percent of the size it will be when you are fully grown.
24. Can the human body regenerate? In fact, if a part of your liver is removed due to injury, disease, or surgery, it will grow back!
25. Of course the human sense of smell isn’t nearly as acute as a dog’s or other animal, but we can still detect and remember about 50,000 different scents.
26. Your small intestine is about 400 percent longer than the height of the average adult.
27. Do you THINK you are a clean freak? Well not matter who you are or how many showers you take a day, every inch of your skin is infested with about 32 million bacteria. But don’t worry – most of them are harmless and many bacteria are actually beneficial.
28. When we sneeze, the air we expel can travel at 100 miles per hour or more.
29. The older we get, the more we snore. In fact, by 60 years of age, 60 percent of men and 40 percent of women will snore. That’s not always pleasant for the person you share a bed with. Just how loud is a snore? Most average about 60 decibels, the level of normal speech, but snores can also reach more than 80 decibels, the level of a drill breaking up concrete.
30. When we are born, our heads comprise one-quarter of our total body length. But by the time we reach adulthood, our heads are only one-eight of our total height.