Februari 09, 2017
inside of your mouth are usually 32 teeth:8 incisors, 4 canines, 8 premolars, 8 molars, and 4 third molars. one of these things isnot like the other… one of these things, doesn't belong! hey toothersthe third molars -- commonly called wisdom teeth -- form as early as age 12 when tissuesacs called follicles migrate to the soft tissues in the back of your jaw to form buds.if they do, they'll erupt from from the gum line by age 25. if you leave wisdom teethin place, they can become impacted, form cysts, get infected, or weaken the bone of the jaw,which is why, after the advent of anesthesia, dentists began removing them. but not everyonehas the same experience! evolution has completely
redrawn the boundaries of the human head,and wisdom teeth got caught in the crossfire. but if there's no room for them, why do weeven have them? 100 million years ago, our ancestors' jawswere large enough to make room for all 32 teeth -- and they were all useful, with molarsdoing a lot of grinding and chewing of greens and raw meats. as we evolved, we didn't reallyneed the big strong back teeth anymore. after the advent of cooking, food became easierto digest and to chew; so again, having a third set of molars was pretty useless. asour ancestral primates took advantage of these evolutionary wins, we began to walk upright,grew larger brains, and developed longer arms; yet, somehow our third molars weren't entirelyeliminated. thanks, mr. darwin.
that being said, 65 percent of people don'tdevelop wisdom teeth at all; and some will only get one, two, or three. in one studyfrom university of tennessee-knoxville, african-americans, and inuits tend to have third molar agenesis,meaning they never develop wisdom teeth buds. in fact, inuits, seem to hardly ever growwisdom teeth. alan mann, an anthropologist from princeton university, believes this isbecause the inuit tend to have flatter faces and narrower jaws. he believes as the braingot larger, there was no more room in our faces, and the evolutionary advantage wentto those who didn't have these superfluous, painful teeth. essentially, their own genetics caused naturalselection to weed out the inuit who did grow
the teeth, as they'd likely experience themedical difficulties associated with those who grow them today, yet have no way to fixit. on top of that, research from the university of pennsylvania found a mutation in a genecalled myh16, which resulted in the shrinking of our jaw, further pushing out these stupidteeth. this process actually started hundreds ofthousands of years ago. while doing research in china in 2011, mann, the princeton anthropologist,found the oldest known fossils without wisdom teeth, dating from 300 to 400,000 years ago.experts think wisdom teeth are similar to pinky toes or human tails -- they're vestigial-- leftover bits in the ongoing process of evolution.
so even though wisdom teeth started out assomething useful, today they are more a pain than a perk! if third molars do appear (andthere's not enough space on your jaw for them to fit) the american association of oral andmaxillofacial surgeons, recommend they be removed. of course, in the end, the fate ofthis vestigial evolutionary tooth it's a matter for you and your dentist. life is weird. testtube now has a newsletter! get a weeklyround-up of our most popular videos across all our shows at
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