Melissa Stewart - Do People Really Have Tiny Insects Living in Their Eyelashes?: And Other Questions about the Microscopic World

DoPEOPLEREALLYHAVE

TINYINSECTSLIVINGINTHEIREYELASHES?

andotherQUESTIONSabouttheMICROSCOPICWORLD

Heres a better question: whose
mouth has more bacteria per
square inch a persons or a
dogs? That question is much easier to
answer. Its pretty much a tie.

Your mouth is wet and warm. Its full
of tiny bits of food. That makes it the
perfect place for bacteria to live and
grow. A dogs mouth is no different.

At any moment, fifty billion bacteria
could be living inside your mouth.
There are other kinds of germs too. A
dog with the same size mouth would
have about the same number of itty-
bitty invaders.

Why do some people think a human
mouth is dirtier than a dogs? Because
the wound from a human bite is
more likely to get infected than
the wound from a dog bite.
But thats because many of
the germs in a dogs mouth
only affect dogs. They can
make another dog sick, but
they cant harm a person.

An insect has three body parts a
head, a thorax, and an abdomen.
It also has six legs. Butterflies and
beetles are insects. But critters such
as mites are not. And its pretty
common for mites to make themselves
at home on peoples eyelashes. In fact,
believe it or not, most
peoples eyelashes
contain mites.

Eyelash mites
have two body
parts and eight
legs. They belong
to the same group
of animals as spiders
and ticks. Eyelash mites look like tiny
worms. A dozen eyelash mites could
easily fit on the head of a pin. They
have stumpy legs with tiny claws. They
spend their days sucking on juices that
ooze out of your skin. Sometimes they
munch on dead skin cells too.

Eyelash mites often spend their
whole lives on a persons eyelashes.
Whenever you blink, they go along
for the ride. Just think about
it: That means these little
creatures bounce up
and down more than
ten thousand times a
day!

A female eyelash mite lays
up to twenty- five eggs at
once. The young mites grow quickly.
In about two weeks, they are ready to
lay eggs of their own.

Most of the time, you dont notice
eyelash mites. But if you dont wash
your face much, they can start to pile
up. Then your eyelashes may fall out
sooner than they normally would.

Itch mites only live on humans,
and they often spread from
person to person. All it takes is a
quick handshake. Luckily, itch mites
are less common than their eyelash-
dwelling cousins. Only
about percent of North
Americans have them.

A male itch mite spends
his whole life on a persons
skin. He doesnt cause
any trouble at all. But the
female is a different story.
She burrows into skin and
builds tunnels more than
inch (2.5 centimeters) long.
As she digs, she sucks on
body juices and lays more
than one hundred eggs.

Chemicals from the females body
cause a rash called scabies. It makes a
persons skin red and itchy. Scabies is
most common under armpits, on wrists
and legs, and between fingers. Getting
rid of scabies isnt easy. Youll have to
visit a doctor. The doctor can prescribe
medicines to ease the itch and kill the
mites.

But dont worry too much the next
time your skin itches. You probably
dont have itch mites. The most likely
cause is a bunch of dead skin cells.
Your skin is your bodys largest organ.

Its made up of billions of cells. All
those cells form deep inside your
skin. Then they slowly move up to the
surface.

By the time the cells reach the top of
your skin, they are dead. About fifty
thousand of them fall off your body
every minute!

Sometimes dead skin cells get stuck.