Despite their small size (three of them could fit in the period at the end of a sentence and about 42,000 of them live in every once of dust) these driven little arthropods have a massive impact, because the Dust Mite does not eat dust – ah, would that dusting had such a dedicated helpmate. Rather they feast on the 50 million flakes (about 1 ½ grams) of skin we shed each and every day. About 80 % of the “dust” you can see floating in a beam of sunlight is your own dead skin, and fodder for these microscopic herbivores. These are the bugs that give spiders the heeby-jeebies!
Our mighty mite companions also enjoy munching on hair, pollen grains, fungal spores and bacteria, as well as cigarette ash and tobacco, clothing fibers, fingernail clippings and filings, food crumbs, glue, insect parts, paint chips, salt and sugar crystals and even graphite; in short everything and anything we are, use or touch, they eat and regurgitate and re-eat and re-regurgitate, etc., etc. (Dust mites have no digestive tracts).
When you sleep (we spend about 1/3 of our lives in bed) your body and bedding is transformed into an Acaroliocal Park (acarology being the study of dust mites) which makes Michael Crichton’s "Jurassic Park" look like it had been stepped on by an Apatasaurous. As much as half the weight in your ten year old mattress could be the 10 million mites who live there and depend on you for their dinner each time you lay you down and go to sleep. Mites don’t like sunlight and they love high humidity, meaning when you climb into bed tonight they will be there to welcome you, waiting for you to exhale and pull the covers up.
They also love rugs and carpets, dusty bookshelves and dusty books and nooks and crannies on fabric covered furniture. And they are completely harmless – except that their poop and their desiccated corpses are a source of human allergies and likely a cause of asthma. During a mite’s lifetime of 3 to 4 weeks she can produce 200 times her own weight in mighty pop and leave 300 cream colored mighty mite eggs, all capable of taking your breath away. A dehumidifier helps with the allergies (dust mite populations drop at anything below 50% humidity) and regular vacuuming can help keep their populations under control. But there are studies showing that carpet or mattress shampooing or even using a Hepafilter on your vacuum cleaner merely increases the resident population because it moistens it and scatters it.
These tiny bugs have evolved so closely with us that there are no conditions or chemicals that will kill them without doing the same thing to us. So basically, the best we can hope for in our war with dust mites is a draw, because the world of the dust mite is a familiar yet strange place where air behaves more like water and a each human hair supports an isolated ethos.
And as every Ying has its Yang, and every Superman has his Bizzaro Superman, the herbivore dust mite has engendered the family Cheyletidae, the micro-predatory dust mite, which can be 6 – 8% of the total mighty mite population. These minuscule lions and tigers and bears stalk their prey every night, even migrating with them onto and off your body, unseen and largely un-felt, pouncing with vicious crushing microscopic jaws. They are no less heartless for their lack of a heart. Some digest their food inside its own shell (something to think about the next time you eat crab) by injecting masticating juices, and some of these tiny predators even consume the shell, reducing their meals to a tiny pile of mush before consuming it.
It even seems that our current mighty mites are the survivors of a once more varied population of “guest workers”, as was attested to by the murder of Archbishop Thomas Becket, just before vespers on December 29, 1170. What was amazing was what happened to the Archbishop’s corpse, as described in Hans Zinsser’s 1935 epic book, “Rats, Lice and History”, beginning with Zinsser’s description of the dead Archbishop’s robes of office.
When he was murdered Becket was wearing, “…a large brown mantle; under it, a white surplice; below that, a lamb’s wool coat; then another woolen coat; and a third woolen coat below this; under this, there was the black, …robe of the Benedictine Order; under this, a shirt; and next to the body, a curious hair-cloth, covered with linen.”
As Becket’s corpse grew cold the successive layers of robes also cooled, and all the little creatures that had been living within the folds and pleats started looking for a new home. Wave after wave of various fleas, ticks, spiders, pincher bugs, and other creatures flowed out from the corpse, “…like water in a simmering cauldron” producing in the hushed mourners gathered in the dim cathedral, “…alternate weeping and laughter…’”. Those Saxons; they sure knew humor when they saw it, skittering across the blood stained marble floor. And the unseen mites must have been far more numerous and just as desperate to find their meal ticket suddenly giving then the cold shoulder.
Not only did the dead Becket popularize the hair shirt, but his corpse offered an abject lesson in the realty of life before the invention of the water heater. Without easy access to warm water people tended not to bathe. And that made them much more intimate with their pests and parasites than we of the hygienic era. But despite our best efforts we still live with the mighty Dust Mite. In fact, if you listen very carefully, you can probably hear them marching across your flesh right now, and everything you touch during an average day, looking for a snack.
Sleep tight, and don't let the dust mites bite. And Trick or Treat and bon appetit.
- 30 -