40 Interesting Facts About Humans Most People Don’t Know

Humans are strange animals. We walk upright, cook our food, blush and cry emotional tears, and talk in thousands of languages. This list covers facts about how humans think, behave and evolved. For facts about organs, bones and blood, see 30 random facts about the human body.

Facts about human evolution and our species

1. We are the last humans standing. Homo sapiens is the only living species in the genus Homo. Neanderthals, Denisovans and others are all extinct.
2. Our species is about 300,000 years old. Fossils from Jebel Irhoud in Morocco push the origin of Homo sapiens back to roughly 300,000 years ago.
3. Any two people are about 99.9% genetically identical. All the visible variety between people comes from a tiny fraction of our DNA.
4. We share almost 99% of our DNA with chimpanzees. Comparing the genomes that line up directly, humans and chimps differ by only about 1.2%.
5. We have fewer genes than rice. Humans have roughly 20,000 protein-coding genes, fewer than some plants, including rice.
6. We are one of very few mammals that habitually walk on two legs. Walking upright freed our hands for carrying and making tools.
7. Our brains are about three times bigger than a chimp’s. An adult human brain averages around 1,300–1,400 cm³, compared with about 400 cm³ for a chimpanzee.
8. Humans are superb long-distance runners. With millions of sweat glands and little body hair, we can shed heat and keep running in hot weather far longer than most mammals.

Facts about the human mind

9. You can’t tickle yourself. Your brain predicts the sensation of your own movements and dampens it, so self-tickling barely registers.
10. Memories are rebuilt, not replayed. Every time you recall a memory, your brain reconstructs it, which is why confident memories can still be wrong.
11. Most people have déjà vu. Surveys suggest roughly two-thirds of people have experienced that eerie feeling of having “lived this moment before”.
12. Songs get stuck in almost everyone’s head. In one large survey, about 90% of people said they get an “earworm” at least once a week.
13. We can probably see about a million colors. The human eye has three types of color-sensing cones, which combine to let us tell apart roughly a million shades.
14. We are wired for curiosity. Learning something we are curious about activates the brain’s reward system. Why are humans so curious?
15. Almost everyone dreams, even people who say they don’t. Most dreams happen during REM sleep and are forgotten within minutes of waking. Why do we dream?
16. We may be able to maintain about 150 stable relationships. Anthropologist Robin Dunbar proposed this limit, known as Dunbar’s number, based on brain size in primates.

Facts about human behavior and emotions

17. We laugh mostly for social reasons. Psychologist Robert Provine found people are about 30 times more likely to laugh when they are with others than when alone.
18. Blushing may be uniquely human. Charles Darwin called it “the most peculiar and the most human of all expressions”.
19. Humans are the only animals known for certain to cry emotional tears. Other animals produce tears to protect their eyes, but crying from emotion appears to be ours alone.
20. Yawns are contagious, especially between people who are close. Why do we yawn?
21. About 90% of people are right-handed. That ratio has been remarkably stable across cultures and throughout history.
22. We blink about 15 to 20 times a minute. That is thousands of blinks every day, yet our brains hide the gaps so the world never goes dark.
23. Humans are the only animals that cook. Cooking makes food easier to digest and may have helped fuel the growth of our large brains.
24. We spend about a third of our lives asleep.

Facts about babies and growing up

25. Babies recognize their mother’s voice at birth. Newborns show a preference for their mother’s voice, which they heard in the womb.
26. Human babies are born with unfinished brains. At birth, the brain is only about a quarter to a third of its adult size.
27. Babies have more bones than adults. They are born with around 270 to 300 bones and pieces of cartilage. How many bones are babies born with?
28. Babies usually start laughing at about 3 to 4 months.
29. Children recognize themselves in a mirror at around 18 to 24 months. This “mirror test” is a classic sign of self-awareness.
30. Humans have one of the longest childhoods of any animal. A long childhood gives our brains years to learn language, skills and culture.

Facts about humanity today

31. There are more than 8 billion of us. The United Nations marked the world population passing 8 billion in November 2022.
32. More than half of all people live in cities. The world became majority urban for the first time in the late 2000s.
33. Humans speak about 7,000 languages. Many are endangered, with fewer than 1,000 speakers each.
34. Global life expectancy is a little over 70 years. It has more than doubled since 1900.
35. No two people have the same fingerprints, not even identical twins.
36. Humans have been making art for at least 45,000 years. Some of the oldest known cave paintings, found in Indonesia, show animals painted tens of thousands of years ago.

Weird but true facts about humans

37. You are slightly taller in the morning than at night, because the discs in your spine compress during the day.
38. Your body gives off a faint glow that is about 1,000 times too weak for your eyes to see.
39. Humans have unusually visible eye whites. Compared with other apes, our white sclera makes it easy to see where someone is looking, which may help us cooperate.
40. Goosebumps are left over from our furry ancestors. Raising body hair helped animals stay warm or look bigger. On us, it just makes bumps.

Frequently asked questions

What makes humans different from other animals?

A combination of traits: complex language, large brains relative to body size, habitual upright walking, cooking, long childhoods, and the ability to build and pass on culture across generations.

What is a fun fact about humans for kids?

Babies have more bones than adults, you can’t tickle yourself, and you are a little taller in the morning than at bedtime.

How long have humans existed?

Our species, Homo sapiens, has existed for about 300,000 years. The wider human lineage goes back millions of years.

How many humans have ever lived?

Demographers at the Population Reference Bureau estimate that roughly 117 billion people have been born in total, so people alive today are around 7% of everyone who has ever lived.

Related articles

• 30 random facts about the human body
• How many bones are in the human body?
• What is curiosity?
• Why are humans curious?

Sources

• Hublin, J.-J. et al. (2017). “New fossils from Jebel Irhoud, Morocco and the pan-African origin of Homo sapiens.” Nature.
• Chimpanzee Sequencing and Analysis Consortium (2005). “Initial sequence of the chimpanzee genome and comparison with the human genome.” Nature.
• Blakemore, S.-J., Wolpert, D. & Frith, C. (1998). “Central cancellation of self-produced tickle sensation.” Nature Neuroscience.
• Provine, R. R. (2000). Laughter: A Scientific Investigation. Viking.
• DeCasper, A. J. & Fifer, W. P. (1980). “Of human bonding: newborns prefer their mothers’ voices.” Science.
• Liikkanen, L. A. (2012). “Musical activities predispose to involuntary musical imagery.” Psychology of Music.
• Dunbar, R. I. M. (1992). “Neocortex size as a constraint on group size in primates.” Journal of Human Evolution.
• United Nations, World Population Prospects 2022.
• Population Reference Bureau, “How Many People Have Ever Lived on Earth?”