The
body parts we don't need
Top 10 Useless Body Parts
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. Nipples
on men
Nipples appear on men because all embryos effectively start out
as "female." The Y chromosome and testosterone are what
make an embryo male. But nipples form before the testosterone
comes into play, so the nipples remain.
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