Dark Banquet - Bill Schutt [84]
“So you think the result would be…?”
“I think the result would be widespread famine and economic collapse, on a planet where the kamikaze mentality has already turned religious extremists into tigers sharpening plutonium claws.”
“Okay…but why the huge effect—the lack of bee-pollinated crops?”
“That’s part of it, Bill. We’d be reduced to harvesting wind-pollinated crops like wheat and corn. But just as important, certain organisms are keystone species—basically nature’s cascade points. Should they go suddenly extinct, or should their numbers be greatly reduced, then the entire system is affected. The honey bee is one of those keystones. Knock them down, near to extinction, and our civilization is gone in five years. Without the honey bee, Rome falls.”
We sat there silently for a minute, watching the chess players clustered at tables near the park’s southwestern entrance.
“Checkmate,” I muttered.
Pellegrino gave another humorless laugh. “You got that right.”*131
Approximately one in three mite species belong to the suborder Prostigmata, and these are commonly known as harvest mites or scrub mites. Many of these species are relatively harmless as adults (feeding primarily on plant material) and some are actually beneficial—aiding in the decomposition of plant matter into humus—a vital soil component for the growth of plants. The problem is that somewhere between 2,500 and 3,000 prostigmatids (most belonging to the family Trombiculidae) have parasitic larval instars commonly known as chiggers.
Considering the grief that they cause, only a few species of chiggers count humans as their primary hosts. In that regard, most chigger/human encounters are accidental and generally end badly for both parties. Instead, a significant majority of chiggers parasitize nonhuman hosts, including many invertebrates (like arthropods) as well as every major group of vertebrates.
Chiggers, like their tick cousins, have a worldwide distribution, which means that you’re just as likely to get bitten by a tick in Central Park as you are a chigger in Tunapuna, Trinidad, and although there are several species of chiggers in the United States (belonging to the genus Trombicula), the most commonly encountered is Trombicula alfreddugesi (while in England it would be Trombicula automnalis and so on).
Although chiggers and ticks do exhibit some similarities, the differences between them are significant enough that they should not be confused with each other.
Besides diet, one major difference between chiggers and ticks is size. Chiggers are nearly impossible to see with the unaided human eye unless they’re clustered together (most are about four-tenths of a millimeter long, which is about one one-hundredth of an inch). Ticks, on the other hand, can be hundreds of times larger.
Unable to hop aboard their prey like the long-jumping fleas,*132 both chiggers and ticks locate their hosts either by actively hunting for them or by lying in ambush and waiting for them to brush past.
What occurs next—bite preparation, the bite itself, and the actual mechanism of feeding—is another area where chiggers and ticks differ significantly.
When attacking humans, chiggers move rapidly to areas of the body where the skin is particularly thin, like the ankles, armpits, or the back of the knees. Unlike ticks, they are remarkably fast runners, although both use a similar combination of sensory stimuli (light, touch, and chemicals) to track their potential prey. Upon encountering regions of the body bound by tight-fitting clothing (like socks, belts, or the elastic bands found on underpants and bras), instead of traveling over the material, chiggers crawl under it—often choosing these areas to initiate their bites.
One of the misconceptions about chiggers