Birds are a group of warm-blooded vertebrates constituting the class Aves, characterized by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, and a strong yet lightweight skeleton.
Characteristics of Birds
Feathers: Birds have feathers which are unique to this class of animals and serve multiple purposes including flight, insulation, and display.
Beak: Instead of teeth, birds have beaks or bills adapted for different feeding habits such as tearing flesh, probing for nectar, or cracking seeds.
Egg-laying: Birds lay hard-shelled eggs which are incubated until hatching.
Metabolism: Birds have a high metabolic rate to support the energy demands of flying and maintaining body temperature.
Skeleton: Their skeletons are adapted for flight, being lightweight but strong.
Classification of Birds
Birds are classified into various orders and families based on their anatomical and behavioral characteristics. Some of the major orders include Passeriformes (perching birds), Falconiformes (birds of prey), and Strigiformes (owls).
From Molecules to Organisms: Structures and Processes
Students who demonstrate understanding can:
Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.
Heredity: Inheritance and Variation of Traits
Students who demonstrate understanding can:
Make and defend a claim based on evidence that inheritable genetic variations may result from: (1) new genetic combinations through meiosis, (2) viable errors occurring during replication, and/or (3) mutations caused by environmental factors.