Birds
Birds are reptilelike animals that maintain a constant internal body temp. They have an outer covering of feathers, two legs that are covered with scales and are used for walking or perching; and front limbs modified into wings.
Birds have a crop which is located at the lower end of the esophagus that helps digest food. They also have a gizzard that helps the mechanical breakdown of food by grinding it. Birds have a four-chambered heart and two separate circulatory loops. There is a complete separation of oxygen-rich blood and oxygen-poor blood. Some birds cannot fly like the ostrich and penguins. The have really big sternums to help keep together the breast muscles because of all the muscle it takes to fly.
Groups of Birds:
Pelicans: These birds are found in all types of aquatic ecosystems, from open ocean to lakes and rivers. All have four toes that are connected by a web. Examples: frigatebirds, boobies, pelics. Birds of Prey: These birds are fierce predators with hooked bills, large wingspans, and sharp talon. Examples: Haeks, owls, condors. Perching birds: This is by far the largest order of birds. Many are songbirds. Examples; sparrows, crows, mockingbirds, cardinals. Herons: Are adapted to wading in a variety of aquatic habitats. Examples: storks, ibises, spoonbills, heron. |