Flight
- More than 9000 species can fly
- Those who are too heavy to fly, often “fly” underwater
- All birds have feathers, protein based structures that provide covering, insulation, and shape
- Front limbs covered with feathers - wings
- More than just wings:
- Birds bones are hollow, to reduce their weight
- Requires enormous amount of energy and lots of oxygen.
- Just two lungs, but they are connected to many sacs to multiply the volume.
- High metabolism allows them to access energy quickly
- Keeps their internal temperature at 41 degrees C (106 degrees F)
- No teeth, just a beak that makes them lighter
- All oviparous, they don’t have to carry them in their body
Feathers of Birds
- Make the birds aerodynamic
- Retains heat
- Cushion during collisions
- Camouflage & identifying a mate
- Common types of feathers:
- Down feathers: provide insulation as well as a cushion
- Contour feathers: cover the body and give it shape and color
- Flight feathers: extend from the wings and tail
Appendages of Birds
- Wings for flying (unless you are a penguin or ostrich)
- Not used to manipulate things
- Long flexible necks are substitutes for arms and hands
- Legs are thin and covered with scales with three or four clawed toes.
- Depends on the type of bird and their function
Skeleton of Birds
- Unusual features of the birds skeleton:
- Upper jaw and lower jaw are elongated and form a beak.
- Many neck vertebrae grant free movement of the head.
- The vertebrae of the tail are free moving and help to guide it in flight
- The trunk vertebrae, the flat ribs, and the sternum are fused to make the trunk a rigid framework
- The large sternum has a central ridge called a keel. It provides attachment for flight muscles
- The clavicles are enlarged and fused, forming the “wishbone.” This also provides attachment for flight muscles.
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