Imagine stepping into a world where the animals wear their skeletons on the outside, some have claws strong enough to crack open shells, and others can even become invisible. Ready to discover the fascinating world of crustaceans?Crustaceans may not be as famous as sharks or dolphins, but they play an essential role in oceans, rivers, and even on land. From the tiniest water flea to the mighty lobster, crustaceans come in all shapes and sizes, and they are some of the most unique animals on Earth.Crustaceans are a group of animals that belong to the arthropod family, meaning they have jointed legs and hard exoskeletons. Unlike humans, whose bones are inside their bodies, crustaceans have a tough outer shell made of chitin. This exoskeleton protects them from predators and gives their bodies structure. But because it doesn’t grow with them, crustaceans must shed their shells in a process called moulting. When a crustacean outgrows its old shell, it cracks it open and wriggles out. For a short time, its new shell is soft, making it vulnerable to predators until it hardens again.There are over 67,000 species of crustaceans, and they can be found in all sorts of environments. Some, like crabs and lobsters, live in the ocean, while others, such as freshwater shrimp, are found in rivers and lakes. Some even live on land, like woodlice, which are often spotted hiding under rocks or logs in gardens. They all share common features—jointed legs, segmented bodies, and antennae, which help them sense their surroundings.One of the most famous crustaceans is the crab. With its sideways walk and massive pincers, it’s hard to miss. Crabs use their claws for defence, hunting, and even communication. Some species, like the fiddler crab, have one claw much larger than the other, which they wave around to attract mates. Hermit crabs, on the other hand, don’t grow their own shells. Instead, they search for abandoned snail shells to live in, swapping them out for bigger ones as they grow.Lobsters are another well-known type of crustacean, and they can live for a surprisingly long time—some over 100 years! They are expert hunters, using their strong claws to catch prey like fish and small sea creatures. But did you know that lobsters aren’t always red? They only turn that colour when cooked. In the wild, they can be blue, yellow, or even spotted.Shrimp may be small, but they play a huge role in the underwater food chain. They help keep the ocean clean by feeding on tiny particles of dead plants and animals. Some shrimp, like cleaner shrimp, even act as underwater dentists, picking parasites off fish in a fascinating symbiotic relationship. There are also pistol shrimp, which have one claw larger than the other. When they snap it shut, it creates a sound so loud that it can stun prey or even break glass in aquariums!Not all crustaceans are found in the ocean. Woodlice, also known as pill bugs or roly-polies, are land-dwelling crustaceans that love damp, dark places. They might look like insects, but they’re actually more closely related to crabs and lobsters. Unlike their ocean relatives, woodlice breathe through gills, which is why they need to stay in moist environments.Crustaceans are an important part of the ecosystem. They help keep the environment clean by eating decaying plants and animals, and they are a crucial food source for many larger animals, including fish, birds, and even humans. In many countries, crabs, shrimp, and lobsters are considered delicacies and are a major part of the seafood industry.However, crustaceans face challenges in the modern world. Pollution, climate change, and overfishing threaten their populations. Many crustaceans rely on coral reefs or mangrove forests for survival, but these habitats are disappearing due to human activities. Scientists and conservationists are working to protect these incredible creatures by preserving their environments and promoting sustainable fishing practices.Crustaceans may not always get the same attention as other sea creatures, but they are some of the most extraordinary animals on Earth. Whether it’s the clever hermit crab swapping shells, the powerful lobster snapping its claws, or the tiny shrimp cleaning up the ocean, these creatures are full of surprises. The next time you visit the beach, look closely—you might just spot one of these fascinating animals hiding in the sand or scuttling across the rocks!.Crustaceans can regrow lost limbsIf a crab or lobster loses a claw or leg in a fight or accident, it doesn’t have to worry too much—it can grow a new one! This process, called regeneration, helps them survive in the wild even after losing a body part.The world's smallest crustacean is microscopicWhile we often think of crabs and lobsters, some crustaceans are so tiny that they can only be seen under a microscope. The smallest known crustacean, Stygotantulus stocki, is less than 0.1 millimetres long—that’s smaller than a grain of sand!.Some crustaceans have see-through bodiesCertain shrimp, like glass shrimp, are almost completely transparent, helping them hide from predators. Their glass-like appearance makes them nearly invisible in the water, which is a great survival trick!Crabs communicate by drumming and wavingSome crabs, like fiddler crabs, don’t use sound to communicate. Instead, they wave their oversized claws or drum on the ground to send messages to other crabs—especially when trying to impress a mate!Barnacles are actually crustaceansAlthough they look more like tiny rocks stuck to ships and piers, barnacles are related to crabs and lobsters. They start life as free-swimming larvae before attaching themselves permanently to a surface, where they spend the rest of their days filtering food from the water..Some crustaceans glow in the darkDeep-sea crustaceans like certain shrimps have bioluminescence, meaning they can glow in the dark! This helps them scare away predators or communicate in the pitch-black depths of the ocean.Crabs have teeth in their stomachsInstead of chewing food with their mouths, crabs have special structures in their stomachs called gastric mills, which work like teeth to grind up food. Some even make growling noises by rubbing these structures together!Coconut crabs can crack open coconutsThe mighty coconut crab is the world’s largest land-dwelling crustacean and has powerful pincers that can snap open coconuts—hence the name! Some say their claws are as strong as a lion’s bite.Some lobsters can live for over 100 yearsLobsters don’t just grow old—they keep growing bigger, too! Some have been found to be over 100 years old, and unlike most animals, they don’t show signs of ageing in the same way humans do.Mantis shrimps have the world’s fastest punchMantis shrimps, a type of crustacean, have punches as fast as a speeding bullet. Their club-like claws strike with such force that they can break aquarium glass and even create tiny explosions of heat and light underwater!
