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Different, Odd, Special
Humans are unusual animals by any stretch of the imagination. Our special abilities, from big brains to opposable thumbs, have allowed us change our world dramatically and even leave the planet. There are also odd things about us that are, well, just special in relation to the rest of the animal kingdom. So what exactly makes us so special? Some things we take completely for granted might surprise you.
First up: Speech
Editor's Note: This presentation was originally published in 2011. It was updated in March, 2016.
SpeechSlide 2 of 21
The larynx, or voice box, sits lower in the throat in humans than in chimps, one of several features that enable human speech. Human ancestors evolved a descended larynx roughly 350,000 years ago. We also possess a descended hyoid bone — this horseshoe-shaped bone below the tongue, unique in that it is not attached to any other bones in the body, allows us to articulate words when speaking.
Next: Upright postureSlide 3 of 21
Upright PostureSlide 4 of 21
Humans are unique among the primates in how walking fully upright is our chief mode of locomotion. This frees our hands up for using tools. Unfortunately, the changes made in our pelvis for moving on two legs, in combination with babies with large brains, makes human childbirth unusually dangerous compared with the rest of the animal kingdom. A century ago, childbirth was a leading cause of death for women. The lumbar curve in the lower back, which helps us maintain our balance as we stand and walk, also leaves us vulnerable to lower back pain and strain.
Next: Oddly nakedSlide 5 of 21
NakednessSlide 6 of 21
We look naked compared to our hairier ape cousins. Surprisingly, however, a square inch of human skin on average possesses as much hair-producing follicles as other primates, or more — humans often just have thinner, shorter, lighter hairs. Fun fact about hair: Even though we don't seem to have much, it apparently helps us detect parasites, according to one study.
Next: No more nakednessSlide 7 of 21
ClothingSlide 8 of 21