“Correct. But look deeper. Look at the legs themselves. What are they made of?”
To be classified as an arthropod, an animal must possess a specific set of physical features. Beetles check every single box on this biological checklist. 1. An Exoskeleton is a beetle an arthropod
“You’ve found something good,” the old man said, pulling out a thick magnifying lens on a swiveling arm. “But you look confused. Let’s ask the beetle itself.” “Correct
“Exactly. An external skeleton,” Grandfather said. “A suit of armor on the outside . That’s the second great mark of an arthropod. We have bones inside. A beetle wears its skeleton like a coat of mail. It’s made of a tough material called chitin—the same stuff in mushroom stems and crab shells.” What are they made of
Unlike mammals, which have internal skeletons made of bone, arthropods wear their skeletons on the outside. This hard outer shell is made of a tough, nitrogen-based sugar called chitin. In beetles, this exoskeleton is particularly robust, providing a suit of armor that protects them from predators and prevents dehydration. 2. Segmented Bodies
The word "arthropod" literally means "jointed foot." Beetles have legs and antennae that are made of distinct segments connected by joints, allowing for complex movement.