Zoology
8 definitions in this category
Amphibian A cold-blooded vertebrate that typically begins life in water with gills, then metamorphoses into an air-breathing adult... Arthropod An invertebrate animal with an exoskeleton, segmented body, and jointed appendages. Arthropods include insects, spiders,... Cephalopod A class of mollusks including octopuses, squids, cuttlefish, and nautiluses, characterized by bilateral symmetry, a prom... Crustacean A large group of arthropods including crabs, lobsters, shrimp, barnacles, and copepods, typically having a hard exoskele... Invertebrate An animal without a backbone. Invertebrates include insects, spiders, worms, mollusks, and crustaceans—comprising over 9... Mammal A warm-blooded vertebrate characterized by hair or fur, mammary glands that produce milk, and typically live birth. Abou... Reptile A cold-blooded vertebrate with scaly skin that typically lays eggs on land. Includes snakes, lizards, turtles, and croco... Vertebrate An animal with a backbone (spinal column). Vertebrates include fish, amphibians, reptiles, birds, and mammals—about 70,0...