Februari 09, 2017
14 useless body parts you have for no reason! 14. goosebumps- when you’re stressed out, tickledor cold, your arrector pili involuntarily contract resulting in goosebumps. also, goosebumps tend to appear during anadrenaline rush or emotional situations like watching a horror movie or looking at a wedding. the smooth muscle fibers usually provide thickinsulation to woodland animals by trapping air between their fur. plus it also aides in the animal’s survivallike porcupines, as it can make them look
bigger and makes them look less vulnerablethan other prey. however, since most humans aren’t equippedwith thick and bushy hair like woodland creatures than our arrector pili serves no vital functionto these benefits. 13. sternalis muscle- it is so rare, that in fact,many people know about it. it runs vertically on top of the pectoralmuscles, on the edge of the sternum. its function remains unknown, and around 8%of humans are believed to possess them. while there’s no easy way to tell if youhave it, a documented series of mammograms showed six out of 32,000 women to have thismuscle.
one theory states that it represents what’sleft of the panniculus carnosus muscles. many animals still have that muscle whichallows them to “twitch†their bodies and allows hedgehogs to roll into balls. 12. wisdom teeth- some people never get wisdomteeth, but for some who do it can be painful and quite a nuisance as it grows in sideways. usually, wisdom teeth don’t erupt untilour late teens or into our early adulthood. wisdom teeth are believed to the evolutionarysolution to our ancestor’s rough prehistoric diets consisting of leaves, nuts, meats androots.
eating these tough foods required extra chewingstrength which resulted in excessive wear of your molars. however, modern tools like a fork, spoon andknife helped make it easier to eat our food and our soft food diet now is less stresson our teeth. in this day and age, it is recommended toremove wisdom teeth once they start growing in due to overcrowding in our jaws and toothaches. 11. male nipples- it’s pretty obvious men don’tneed lactate to feed their babies as women do, but up until the y- chromosome is determinedafter the fourth week of development, all
embryos start off the same. but don’t worry, this isn’t somethingto freak out about. it isn’t until the eighth week that thecells begin to undergo sex determination, but males having nipples doesn’t contributeto any evolutionary gain and it doesn’t hurt anything as well. while male breast tissue and nipples serveno primary function, it is perhaps best protecting the lungs and heart from injury. but believe it or not, it is possible formales to produce milk from their nipples and they can develop breast cancer because a certainlevel of estrogen is present in all men.
10. body hair- while body hair plays a vital rolein appearance, is it all that necessary? it is usually believed that people who havea lot of body hair are perceived as masculine, and women get rid of their body hair entirelythrough shaving and waxing. however, your eyebrows and eyelashes are anexception in this case. your eyebrows help prevent sweat and moisturefrom your eyes and your eyelashes protect the eyes from dirt and debris. body hair is just another reminder of evolution,as our prehistoric ancestors were probably all covered in hair to protect them from harshliving environments.
9. appendix- this small body organ is attachedto your large intestine at the cross of the small intestine. it was believed the appendix was essentialin aiding in digestion, but that belief has been proven wrong. at least one in twenty people have their appendixremoved and about 300,000 people every year in the united states due to a painful inflammationknown as appendicitis. however, in plant-eating organisms, the appendixresides as part of the digestive system. as of now, these vestigial organs remain asproof of evolution and embody a function that
was once vital to surviving. 8. palmaris longus- about 14% of the world’spopulation lacks this thin tendon that attaches to the bottom side of the wrist. it has no valuable effect on grip since itis so weak and it also doesn’t cause any motility effects if it is removed. this quality makes an ideal choice for usein tendon grafts because it can be moved without issues. to visibly see it, hold out the palm of yourhand in a flat position.
then close your hand so you can press yourthumb between your fingers. doing so would cause the tendon to pop outof your wrist lightly, some are more pronounced than others. 7. cervical rib- also known as a neck rib, itis an extra body part that stems from the seventh cervical vertebra. some people may have a cervical rib on theleft, right, and even both sides. the discovery of cervical ribs usually poseno danger, and it varies in size and shape. a pair of cervical ribs is believed to theleft over from the age of reptiles, and less
than one percent of the population are knownto have a cervical rib. sometimes, certain conditions can be causedby cervical ribs like artery and nerve problems and weakness. 6. gallbladder- the gallbladder is not a vitalorgan required to function and some people who have their gallbladders removed experienceno issues. in fact, most people don’t notice any changein their digestion and only a small percentage of individuals sense any real complications. obviously, without a gallbladder, your bodycan no longer store bile, which is a liquid
that helps you digest fatty substances. it was once believed removing your gallbladder,and the bile caused severe problems in food digestion. however, removing it serves no threat andmost animal species on earth don’t even have gallbladders. 5. tonsils- your tonsils sit at the back of yourthroat and serves as part of your immune system to fight off infections. tonsils usually get rid and swell up whenyou get a sore throat.
if you open your mouth real wide and lookin the mirror, you can probably get a glimpse of it. some people argue that we don’t need ourtonsils and they are an evolutionary trait that is no longer recognized. many kids have their tonsils removed growingup due to tonsillitis, and it’s pretty evident, we don’t need to them survive. however, i would say i’ve become attachedto mine. 4. paranasal sinuses-while it may be hard tobelieve, our sinuses may be a vestigial organ.
they are small pockets of air that residein our face, and their function has been a topic of debate. the paranasal sinuses of our early ancestorsmay have been equipped with odor receptors that heightened our sense of smell which wasvital to hunting and survival. biologist still don't know why we retainedour mucus-lined nasal cavities over time since it proves to be a nuisance now rather thanhelpful. it seems like all they do now is make ourhead feel lighter to warm and moisten the air we intake. plus, we can do without all the sinus headaches.
3. tailbone- most mammals like kangaroos usetheir tails to balance, and some use their tails to swat away insects and flies. other animals like monkey use their tailsto help them swing in trees and grab branches. obviously, humans don’t have tails, andthat’s what sets us apart from animals. however, if you trace your history far backenough, then you’ll discover that your ancestors did have tails! as humans learned how to walk, the tail wasno longer needed and over time it became fused vertebrae, we know call a coccyx.
the remnants of the tailbone are attachedto ligaments, tendons, and various muscles. 2. fingernails- other than beautiful manicuresor peeling an orange, what’s the purpose of fingernails? fingernails are a subject of debate. we know that fingernails aid to protect theskin on our fingers and at the beginning of time studies show they served as claws. while fingernails still prove to help usethe hands, rip, scratch and perform delicate tasks most people now don’t use them asclaws.
in fact, nails are often trimmed down to preventscratching and to less a number of bacteria that can get trapped underneath our fingernails,which can lead to sickness. 1. pinky toe- life without your pinky toe isn’tall that different. if you were born without your pinky toe orlost it in an accident, you’re still able to do everything you want. so what’s the point of having a fifth toeif we don’t need it? well, that answer is traced all the way backto the beginning of time. primates used their feet to claw, climb andgrab trees.
the pinky toe served to give us a good grip,however, that function is completely obsolete. our balance comes from 26 bones that makeup the forefoot, hindfoot and midfoot. your toes are located in the forefoot, andthe main bones are the metatarsals. so, while the pinky toe serves no primal function,our metatarsal is essential to help us walk, skip, jump and run.
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