5 Useless(?) bodyparts Explained. These bodyparts are all considered useless. But are these bodyparts really useless? Nipples, wisdom teeth, they are all in the list!
5. Nipples on men
All men start off as women. All embryos begin female, and if it masculinizes, it becomes male but keeps much of the same anatomy. Nipples are the same in men and women, but without an influx of hormones like estrogen, they're simply chest ornaments on men.
4. Appendix
The appendix is a vestigial organ, which means it has lost most of its ancestral function. “One idea is the human appendix is remnant of what used to be a larger fermenting chamber in our gut,” according to one doctor. Since humans stopped eating uncooked or low-quality foods like grass, this chamber is no longer useful.
3. Tonsils
Tonsils are technically lymph nodes – part of the lymphatic system, which is vital to your immunity. Your oral cavity is an entryway to your body, so immune cells in your throat can help you fight respiratory infections. Sometimes your tonsils get inflamed and infected, which is when they're removed. Your lymph nodes are incredibly important, but there's some redundancy, so if a pair is taken away, you can survive without them…
2. Wisdom teeth
Like monkeys, men have three permanent sets of molars. Until recently, wisdom teeth were never an issue for humans. Teeth don’t change size. They’re grown before you use them, and then they erupt to the surface. Jaws are bone and, like the rest of your body, need to be supported and used in order to grow properly. Since humans now eat soft, cooked foods as children, our jaws don’t grow to the full capacity, causing problems with wisdom teeth…
1. Armpit Hair
There’s no definitive story for underarm hair, but its location offers a clue. There are two types of sweat glands in your body: eccrine and apocrine, the latter of which are mostly in your armpits. You use apocrine for sexual signaling. Presumably, the hair holds on to the secreted odors so that they stay around long enough for a potential mate to catch a whiff… Ugh!
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