What is a vertebrate fish?

Vertebrate fish are animals that have backbones; the term is usually used in reference to fish or fish-like vertebrates that live underwater. These aquatic creatures have paired fins that help them move quickly in the water, gills to acquire oxygen for breathing, and skeletons made up of bone or cartilage. The vertebrae provide the structural support needed for movement, and some species carry bony scales that make up their exoskeletons. Additionally, they contain internal organ systems and a closed circulatory system that pumps blood throughout their bodies. Many species also possess sensory organs including eyes, ears, and even some types of sensors for navigating their environment. They come in numerous colors, sizes, and shapes including bony fishes, sharks, and rays among others. Some live their entire lives in rivers, lakes, and oceans while others migrate for the purpose of hunting and breeding. It is a diverse group of organisms that fill essential roles within their marine habitats around the world.