There are some creatures whose appearance alone inspires dread and alarm, regardless of whether they actually pose a threat to humans. Among the unloved animals in the category are the centipedes.
These ancient organisms, with their long segmented bodies and many pairs of legs, seem to awaken instant revulsion in people. Most of them are harmless, however, and even those that can deliver a painful bite have to almost be forced into doing so.
Centipedes are not insects but are members of the large group of invertebrates called arthropods, which includes crustaceans, insects, spiders, scorpions and the myriapods. The myriadpods, which literally means "ten thousand feet" are centipedes, millipedes and some other creepy crawlies with lots of legs. But not 10,000.
Even the word "centipede," as most people know, is mostly an exaggeration, for most of them have far fewer than 100 feet. Interestingly, centipedes always have an odd number of body segments, each with a pair of legs, so no centipedes actually have 100 legs.
Centipedes are predatory, and they have a pair of legs that are specially modified into a pair of small pincer-like hollow claws called forcipules. These are concealed under the centipede's head, and can be used to inject venom into prey.
Only the bigger species of centipedes have forcipules that are capable of penetrating human skin, and they only do so in defense, like if they were picked up and squeezed or stepped on by a bare foot. Very few people get bitten by centipedes. But you can watch a YouTube character called Coyote Peterson get deliberately bitten by a giant desert centipede, if you want to experience it vicariously. It looks very painful.
Centipedes are either blind or have very rudimentary sight organs — some of them can tell light from dark, but none of them can distinguish shapes or objects. If a centipede is heading towards you, it definitely isn't doing so deliberately, because it can't see you.
Centipedes are entirely nocturnal, and avoid both sunlight and artificial light. This is probably due to their need to avoid water loss — they lack a waxy coating over their exoskeleton, so they can dry out quickly. Despite this, they are often found in desert or arid environments, but they spend their time in more moist locations, hidden under rocks, logs and bark, in burrows or in the soil itself.
This requirement to avoid the desiccating force of sunlight is one more reason that people find centipedes unnerving — creatures of the night are usually regarded with suspicion. Centipedes themselves are preyed upon by a wide variety of animals, including beetles, spiders, mice, lizards, snakes, birds, bats and more.
We have many different species of centipedes in the Tehachapi Mountains. The larger ones may be slightly greenish tan and may reach five inches long. More common are the reddish brown Geophilomorphs, commonly known as soil centipedes. These are often very thin, wormlike centipedes found in soil or under wood. These aren't capable of breaking human skin with a bite, and feed on soft-bodied creatures like insect eggs or juvenile earthworms.
If you look closely at a centipede, you can see that each pair of legs is slightly longer than the pair in front of it, so that they don't keep stepping on their own feet. As a result, the legs near the back of a centipede may be twice as long as the ones near the head.
Centipedes have been found in the fossil record going back more than 400 million years, making them among the oldest of all living land animals. Fossils of a type called Euphoberia have been found that were more than three feet long. Don't worry though, they're long gone. The biggest in the U.S. today are only about 8 inches long. In the Amazon, one species reaches about a foot long, the biggest on Earth today.
Centipedes are widely feared, but pose little threat to humans. And no, despite the old myth, each of the legs is not tipped with venom that will leave a track of red welts if they walk across you. Centipedes are primitive, blind creatures from our planet's distant past that have somehow managed to evade many cataclysms and survive to the present.
Have a good week.
Jon Hammond has written for Tehachapi News for more than 30 years. Send email to firstname.lastname@example.org.