ISSUE IV

22 SIENNA SOLSTICE
Demodex
Morgan Rondinelli
You have mites on your face. Yes,
you. Nearly 100% of humans do. We are
inoculated shortly after birth, by our mothers
or those otherwise in closest proximity
to us. This gift of mites has been given for
thousands of generations, likely since before
we were considered modern Homo
sapiens. The mites are called Demodex,
species names D. folliculorum and D. brevis.
If you take a plastic slide and scrape
it along your nose or eyebrows, and then
put the oils and dead skin under a microscope,
with a good eye and a bit of luck,
you can see these mites for yourself. They
have eight legs, like all mites, which are
technically arachnids, cousins of spiders
and ticks. But rather than thin, long legs
like a spider, Demodex have fat, stubby
legs attached to their fat, little bodies.
They use these to grasp onto a hair, the
rest of their body sticking slightly out of
the follicle. They’re honestly kind of cute.
I know this, not from seeing Google
images of Demodex, though I’ve seen
plenty of those too, but from seeing my
own Demodex mite. We did this as a lab
exercise in my undergraduate Ecology of
Human Parasites class. We had dissected
worms and fish, but this is the lab I
remember most. Dr. Chelsea Wood stood
at the front of the lab room showing us
images of what we should be looking for
amongst our own skin. Then, she walked
around checking everyone’s microscopes
when they thought they had found one.
We all stayed hovered over our microscopes,
only taking breaks to scrape more
dead skin onto a slide, both excited and
disgusted about the prospect of seeing a
mite from our own faces. Suddenly, I saw
legs. Eight legs and a tube-like body. And
then I excitedly bumped my microscope
out of focus. I had likely found Demodex,
and then I had lost it. Carefully, I zoomed
out. I scrolled back and forth and back and
forth, and was able to relocate the mite. I
sighed with relief, though more carefully
this time so as not to hit the microscope
again. I raised my hand and ushered over
Dr. Wood. She looked down the lens for
a few seconds while I waited anxiously.
So often, we thought we had identified a
specimen, but when Dr. Wood checked,
really it was just an air bubble. But Dr.
Wood then confirmed, “Yep! You found
one.” She brought my slide up to her more
powerful microscope to take some nice
pictures. My classmates each took turns
looking at my Demodex. Though the prevalence
rate on humans is estimated in the
upper nineties, I was the only one in my
class to find a mite. It’s a bit of a blind
search to go through random dead skin
on a microscope slide. But finding one of
my own Demodex mites earned me ten
bonus points towards the final exam, so I
didn’t mind. My classmates insisted that I
name the lone mite. We named it Jimmy.
As a biologist, I know there is life
on me and within me, and I mean that
literally. Besides mites like Demodex, I am
home for a multitude of bacteria. They live
in my gut, between my teeth, on my skin.
My microbiome is everywhere I am. The
bacteria in my digestive system are part