Transcript Birds
Birds February 24, 2011 Objectives • Identify the characteristics of birds • Identify the adaptations birds have for flight • Explain how birds reproduce and develop Bird characteristics • Feathers • Scales • Lay eggs Bird eggs • Amniotic eggs with shells • Shell made of calcium carbonate (same material as seashells, limestone, and marble) • Egg fertilized internally before shell forms • Female lays eggs in some form of nest • Group of eggs is called a clutch • One or both parents incubate eggs and young birds are cared for by one or both parents Flight adaptations • • • • • • • Hollow but strong skeleton Wings Feathers Strong flight muscles Efficient respiratory system Well developed eyesight Tremendous amounts of energy Hollow bones • Many bones joined together to provide extra strength and stability • Hollow bones filled with air • Large sternum • Spine supports tail feathers for steering and balancing Feathers • Birds are only animals with feathers • 2 types of feathers – Contour feathers – Down feathers • Contour Feathers- strong lightweight feathers that give birds their coloring and shape and that are used for flight Feathers • Down Feathers- soft, fluffy feathers that provide an insulating layer next to the skin of adult birds and that cover the bodies of young birds • Birds are endotherms • Feathers allow birds to maintain constant internal temperature • Feathers grow from follicles Feathers • Birds have an oil gland that allows them to keep feathers healthy in a process called preening • Preening- process in which a bird rubs oil from an oil gland over its feathers to condition them Wings • Not all birds fly • Wings are attached to chest muscles • Curved on top and flat or slightly curved on bottom • Air pressure greater on bottom than on top creating lift • Penguins use wings to swim and ostrich use wings for balance Digestive System • Eat high energy foods like nuts, seeds, nectar, insects, and meat • Food is broken down quickly • Food moves into crop for storage, then to stomach, then to gizzard for grinding, then to the intestine Respiratory System • 2 lungs • Each lung connected to an air sac • Birds receive oxygen when they inhale and exhale (unique to birds) Circulatory System • Heart, arteries, capillaries, veins • 4 chambered heart which is large for their bodies • Oxygen filled blood is kept separate from carbon dioxide filled blood • Rapid heart beats Importance of birds • • • • • • Source of food Pets Control pests Flower pollinators Can be pests Carry disease Peacock Chicken Blue bird Baby chickens Sea Gull American Bald Eagle Assignment • What type of feather helps birds maintain their body temperature? • Compare and contrast birds that fly and do not fly • Why do most birds eat nuts, berries, insects, nectar or meat but not grass or leaves.