鸟龙, or "Bird," refers to a group of warm-blooded vertebrates characterized by feathers, wings, and beaks. They belong to the class Aves and are known for their ability to fly, although some species are flightless. Birds are found in diverse habitats around the world, from forests to deserts, and they play essential roles in ecosystems, such as pollination and seed dispersal. Birds exhibit a wide range of sizes, colors, and behaviors. They lay eggs, which are often incubated in nests. Many species, like the Bald Eagle and Hummingbird, have unique adaptations that help them survive in their environments. Their songs and calls are also important for communication and mating.