Arthropod
Channel: English Unpacked
Date: 2023-10-30

Arthropod is a term used in biology to describe a large group of invertebrate animals that have jointed legs and a hard exoskeleton. The word "arthropod" comes from the Greek words "arthron" meaning joint, and "podos" meaning foot. This name accurately describes the defining characteristic of these animals – their jointed limbs.
Arthropods are incredibly diverse and can be found in various habitats all around the world. They include insects, spiders, crustaceans (such as crabs and shrimp), and millipedes. Here are a few examples of arthropods:
1. Insects: This is the largest group of arthropods, with over a million identified species. Insects have six legs, a segmented body, and typically a pair of wings. Examples include butterflies, ants, bees, beetles, and flies.
2. Spiders: These arthropods belong to the class Arachnida. They have eight legs and two body segments – the cephalothorax and the abdomen. Examples include spiders, scorpions, and ticks.
3. Crustaceans: This group includes animals like crabs, lobsters, shrimp, and barnacles. Crustaceans have two pairs of antennae, two body sections (cephalothorax and abdomen), and multiple pairs of legs.
4. Millipedes: These arthropods have a long, segmented body with many legs. Despite their name, millipedes don't actually have a thousand legs – most species have between 30 to 400 legs. They are often found in moist environments and feed on decaying plant matter.
It's important to note that while all arthropods have jointed legs and a hard exoskeleton, they can vary greatly in size, shape, and habitat. Their diverse adaptations have allowed them to thrive in almost every corner of the Earth, making them one of the most successful animal groups on the planet.