Chordates

Chordates are a diverse group of animals characterized by having a notochord (a flexible, rod-like structure supporting the body), a dorsal nerve cord, and pharyngeal slits at some stage of development. This group includes vertebrates like mammals, birds, reptiles, amphibians, and fish, as well as some invertebrates like tunicates and lancelets. These features are key for their body support, nervous system development, and feeding. Chordates typically have a segmented body plan and bilateral symmetry, and many develop a backbone or similar structure, making them an essential group in understanding animal evolution and biology.