Human Quirks You Didn't Know Have Evolutionary Origins

Why do we share so many strange little tics, and where did they come from? What purpose do they serve? Turns out we can answer some of those questions ... (click for full) http://goo.gl/ffoP0d
  1. Sticking Out Your Tongue When You Concentrate Is A Remnant From The First Language
    Going from frantic grunting to quoting Shakespeare would have been a rather large leap for our club-bearing ancestors to make. As such, the earliest languages basically consisted of playing charades -- that is, mimicking common acts such as hunting, eating, or bashing skulls in with your club when Tok Tok doesn't get that hand-to-mouth means "eating." Jesus Christ, Tok Tok, get your shit together.
  2. Sighing Prevents Suffocation
    Your lungs contain scads of tiny air sacs called alveoli, which exchange carbon dioxide for oxygen, allowing you to continue doing your two favorite things: living and breathing. Thing is, they also tend to collapse over time. Luckily, we also have a built-in mechanism for preventing that: taking an extra-large gulp of air, also known as a sigh. This simple act pops those little bastards right back open and keeps you living, no matter how badly you wish you could die already.
  3. You Talk Like That Because Of The Environment
    The "acoustic adaptation" theory posits that a region's climate has a direct and profound effect on the languages that develop in that area. In essence, the evolution of a place's lingo is influenced by the landscape, temperatures, and even rainfall of the locale, all of which are factors determining which sounds will be used frequently and which won't. The reason is simple physics: Sound waves don't behave the same in the woods as they do in open fields etc.
  4. Shaking Your Head Originally Meant You Were Full
    Since babies don't have the whole "language" thing down yet, they simply turn their heads away from food when they're full. This simple denial of food mentally links the gesture to the concept of negation, and it's this relationship which survives into our adult lives, where it can serve many purposes, ranging from "not hungry" to "not right now" to "that is not my German porn, and I will not dignify your accusations with a verbal response."
  5. Scowling Is Flexing (With Your Face)
    Professors set out to explain why the contraction of seven distinct muscle groups -- "lowered brow ... raised cheekbones (as in a snarl) etc. -- is the universal human expression of anger. To do so, they isolated each component of the "anger face" and showed the resulting computer-generated faces to test subjects. Subjects reported that the expressions made the depicted individual look physically stronger.
  6. We Call Our Parents "Mama" And "Dada" Because They're The Easiest "Words" To Say
    Actually, linguistics pioneer Roman Jakobson solved this peculiar phenomenon decades ago. He theorized that babies aren't simply hopelessly unoriginal, but rather desperately trying to get a grip on this whole "articulation" thing. This process mainly involves a buttload of gibberish, but Jakobson discovered that there's a technical side to it as well. Speech sounds are acquired in a specific order, based on their complexity.