Myriapods

Nature Notes by Dr. Frank Lang

Arthropods include insects, spiders, crustaceans and the like. They have external hardened shells that serve as a skeleton and an internal system of muscles. If you have ever eaten cracked crab you know how arthropods are put together. In case you worry about such things, bugs big enough to eat Los Angeles will never happen, science fiction notwithstanding. Even if they had the stomach for such a disgusting task, their structure, physiology, and gravity strictly limit their maximum size.

There are two other groups of arthropods, centipedes and millipedes. Centipedes are fast, have one pair of legs per body segment, and are predatory. Millipedes are slow, have two legs per body segment, and are vegetarians. I first knew these creatures as thousand-legged worms, until study taught me otherwise.

When I was a child wandering through the damp woods of western Washington I would commonly encounter a handsome black millipede with bright yellow spots along its sides. Disturbed, the beast would roll up into a tight spiral, head end in, and begin to stink. Not an ordinary stink, but one, when smelled at a distance, that reminded me of my Auntie Winnie’s German Christmas cookies, the faint odor of almonds.

Years later I learned that most millipedes have a series of glands along their bodies. These glands generate various noxious compounds, including hydrocyanic acid and cyanide gas, which has the odor of almonds. The millipede’s striking color warns potential predators of an unsavory mouthful.

In 1974 I spent a year-long sabbatical in Texas. Every thing is bigger and better in Texas, including centipedes. I was used to northwest centipedes, a couple of inches long at most, who spend their lives poking around in rotten logs. On a Biological Photography Association field trip I turned over a rock. There was a centipede, that was a centipede, six or eight inches long, bright yellow head, sinister black body and almost as fast as I was. There is no photographic record of the encounter. Looked to me like it might eat puppies.

On my second sabbatical in Massachusetts we lived at 10 Swan Street in a house built in 1812 that was rumored to harbour the ghost of a Revolutionary War soldier. One evening out of the corner of my eye I noticed motion along the baseboard. A shifted glance and nothing. A few nights later the same sensation, still nothing. Spooky thoughts on my part. Whatever it was, it was fast. The next night a rolled up newspaper solved the mystery. From what I could reconstruct, it was a long-legged multisegmented creature, that moved fast, real fast. As visiting scholar at Harvard I had the run of the library at the Museum of Comparative Zoology, or the MCZ as insiders say. There I discovered that I had done in a house centipede, a creature that feeds on silverfish, cockroaches, and flies and should be welcomed in any household. The remainder of my time at 10 Swan Street I attributed unexplained motion to house centipedes and not to ghosts – and left both unmolested, just in case.

— Dr. Frank Lang

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