Top 10 Useless Body Parts

BAK

JF-Expert Member
Feb 11, 2007
102,796
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Top 10 Useless Body Parts
By The Science Channel

When you're sick you may feel that certain body parts are more trouble than they're worth. And in some cases, you'd be right. While the human body has evolved and adapted significantly since the caveman days, a few biological traces of our prehistoric ancestors still remain with us in the form of freeloading body parts we lug around with us, but have no use for. Take a gander at the top offenders!


10. Plica semilunaris
You may not know it, but you have a third eyelid. Pull open the two more noticeable eyelids and take a look -- it's located right in the corner by the tear duct. This small third eyelid is left over from what's known as a "nictitating membrane," which is still present in full form in some animals including chickens, lizards and sharks.


9. Body hair
No doubt we were once hairier. Up until about 3 million years ago, we were covered with body hair. But by the time Homo erectus arrived, the ability to sweat meant we could shed our woolly ways.


8. Sinuses
Doctors don't really know much about sinuses -- only that we have a lot of them. Possibilities for their function range from insulating our eyes to changing the pitch and tone of our voice.


7. Adenoids
Adenoids trap bacteria, but they're also prone to swelling and infection. Just ask any 7-year-old. Luckily, our adenoids shrink with age and are often removed, along with ...


6. Tonsils
Also prone to swelling and infection. If you still have them when you reach your 30s, it's almost an accomplishment.


5. Coccyx
More useful as a game-winning Scrabble word than as part of the anatomy, the coccyx or tailbone, is made up of several fused vertebrae left over from the olden days when we had tails.


4. Arrector pili
When we were hairier (see No. 9), the arrector pili made the hairs stand on end when we needed to appear bigger and scarier. Now, it just gives us goose bumps.


3. Wisdom teeth
Back in the day, when we ate mammoth meat off the bone and didn't floss afterward, our teeth tended to fall out. Therefore, when those reserve molars, aka "wisdom teeth," came in, they were welcomed. Nowadays, fluoride and dental plans have made them just a huge pain.


2. Appendix
Darwin claimed the appendix was useful for digestion during our early plant-eating years; it's dwindled down to little since we started eating more digestible foods.

1. Male nipples
Because, why?

Did we miss any parts that you think are useless?
 

Kinyau

JF-Expert Member
Nov 24, 2006
906
1,000
thanks for the knowledge of this vestigial organs, but I doubt about the plica semilunaris. Doenst it add more protection to the eye since eyelids protect against external dust, insects that may harm the organ?
also male nipple?its not vestigial, why, I dont know.
 

mwewe

Senior Member
Jul 17, 2007
125
0
Ukataji vimeo ni very common huko vijijini. It appear our ancestors were smart than we want to believe.

Vipi kuhusu jando!
 

Kilongwe

JF-Expert Member
Feb 7, 2008
424
195
jamani kuna vingine vina kazi ya mapambo ingawa hayo mapambo kwa baadhi ya watu huona ni kero au uchafu,nakumbuka kwa ndugu zetu wa China huwa wanashindana kwa kuwa na Nywele ndefu kwnye makwapa au kule sehemu wakati sisi huwa ni kama uchafu...Naomba toa hoja
 

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