Millipedes and centipedes are similar looking arthropods, but unlike millipedes, centipedes rely on venomous bites for defending against predators. Millipedes, on the other hand, do not produce venom; instead, millipedes secrete toxic compounds from each one of their body segments in order to repel threatening insects. Millipedes are also herbivores while centipedes are carnivores. For the most part, millipedes have evolved passive forms of defense for handling threats. For example, upon being stepped on, millipedes will curl up into a defensive position in order to prevent their exoskeleton, and especially their head, from becoming fractured. For the greater part of history, experts believed that all millipede species relied on chemical forms of defense, but a study conducted two decades ago described a new species that relies on a unique form of mechanical defense. Unlike most millipede species that possess smooth exoskeletons, the Polyxenus fasciculatus species’ body is covered in hairs. The thick hairs located toward the rear of this species’ body entangles predatory insects upon attack. Once these hairs, or tufts, have entangled an insect predator, they detach from the millipede’s body, leaving behind an insect struggling to free itself from the trap. Eventually, the trapped insect dies after a long struggle.
The P. fasciculatus millipede species was first discovered in Florida in 1997 and it is a uniquely small species, as it only grows to be an eighth of in an inch in length. Ants are this species’ primary predator and they usually don’t stand a chance of surviving after literally tangling with these porcupine-like creatures. The many tufts on this millipede’s body hook into ants, and the more ants try to escape, the more entangled they become. In some cases, the hooks alone will kill an ant quickly if enough tufts become stuck within its body. Amazingly, this millipede species has more than enough tufts to defend itself successfully against a large group of ants, and they regrow these tufts with every molt. In fact, just about any millipede predator will be killed upon attacking the P. fasciculatus species. These common millipede predators include beetles, spiders, pseudoscorpions and even centipedes. Arthropods that are as small as the P. fasciculatus species rarely survive violent encounters with predators that are ten times their size, making the P. fasciculatus species a truly unique arthropod.
Can you name any other arthropod species that can successfully defeat much larger sized predators?
Tags: exterminator, pest control