It's well established that Barbie isn't exactly designed according to naturally occurring female measurements. Her chiseled boyfriend Ken isn't a perfect chip off the ol' human male block, either. Sure, his abs of steel (or plastic, rather) are achievable via Malibu-caliber diets and exercise, but no gym rat will ever be able to sculpt pectorals quite that smooth since Ken -- and Barbie, too, for that matter -- has no nipples. But that doesn't imply that Ken is somehow less of a (fake) man for not having them. Evolutionary biologists have long puzzled over why male nipples have hung around the male chest for so long considering the minimal purpose they serve, aside from offering another enticing spot for a body piercing. Some consider them useless enough to qualify as vestigial anatomy. And in that light, when you think about it, nipple-less, wisdom-teeth-free and appendix-absent Ken could be the model of a future, more highly evolved man. That said, he would also be a man unable to reproduce and pass along that hunky musculature, Ken's ultimate Achilles heel.
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