Myriapods, belonging to the phylum Myriapoda, encompass several multi-legged invertebrates, including centipedes, millipedes, and their relatives. These terrestrial arthropods are distinguished by their segmented bodies with numerous legs, varying from dozens to hundreds. They occupy diverse habitats, ranging from the forest floor to arid deserts, thriving in environments that offer moisture and decaying organic matter. Myriapods evolved over 400 million years ago, adapting to fill various ecological niches. Centipedes are primarily predatory, while millipedes generally consume decaying vegetation. As ancient creatures, they provide insights into the evolution of more complex arthropods and play essential roles in soil health and ecosystem functioning.
Myriapods are recognized by their elongated bodies composed of many segments, each typically bearing a pair of legs, resulting in a multitude of limbs that give these creatures their name. Centipedes, the carnivorous ones, have a flatter body and one pair of legs per segment, allowing for swift movement. Millipedes, in contrast, have a more rounded body with two pairs of legs per segment, adapted for burrowing and a slow-paced lifestyle. Neither group can speak, but they sense their environment through antennae sensitive to chemicals and vibrations. Myriapods breathe through tiny holes called spiracles and lack complex eyes, relying on their other senses to navigate their surroundings.
Throughout history, humans have had a varied relationship with myriapods. Centipedes and millipedes, although often overlooked, play crucial roles in ecosystems as decomposers and predators. In some cultures, centipedes are symbols of power and used in traditional medicine. Myriapods have also skittered into pop culture, appearing as eerie creatures in films and literature, often eliciting a shiver from audiences.
Conservation efforts for myriapods are not as prominent as for other animals, yet their decline can indicate environmental issues, prompting studies and protective measures in certain habitats. Understanding and preserving these many-legged invertebrates is vital for maintaining ecological balance.
Myriapods typically have more than 6 legs as well as one pair of antennae. The number of legs a myriapod has depends on its classification as millipedes can have between 36 to 400 legs. Other classifications like the Symphyla are born with 6 legs, but grow others throughout their lifetime.
The primary characteristics of myriapods include having a segmented and worm-shaped body that is not soft, but hard due to mineral salts in their environment. Myriapods also have a head with a pair of antennae, a long body divided into 2 regions, tracheal breathing, and embody terrestrial behavior.
Myriapods first appeared about 428 million years ago. This discovery was made through the fossil of the myriapod, the millipede, Pneumodesmus newmani. The Pneumodesmus newmani is also important as it is the earliest known terrestrial animal. The overall fossil record of myriapods extends back into the late Silurian period.
