1. Ch Birds
Class  Aves
No other vertebrate is as well adapted to life on land, air, & water.
The study of birds  Ornithology
Archaeopteryx was the 1st reptile-like bird fossil known.

2. Characteristics of Birds
1. Feathers
2. Endothermic – warm-blooded
3. 4-chambered heart
4. All lay eggs
5. Most without teeth (beaks)
6. Hollow bones (most)
7. Forelimbs modified into wings
8. Hind limbs for walking, swimming, or perching

3. These are modified scales in a bird.
Feathers
The 2 main types of feathers are contour & down feathers.
Parts of a Feather: Quill Shaft Vane (made up of barbs)  Barbules with hooks
Draw a feather

4. Each barb on the vane is attached to the next barb by the barbules’ hooks.
A bird uses a preening technique to repair any split vanes by rehooking the barbules with its beak.
The down feathers are the fluffy short feathers close to a bird’s skin.

5. Most water fowl use their tail gland to spread oil on their feathers to keep them water proof.
What’s the term for birds replacing their feathers?
A grown feather is a dead structure that eventually breaks off through shedding.

6. 2 Types of Molts
1. Serial molt – feathers are lost in series; flight is still possible.
2. Eclipse molt – contour feathers are all lost a once; the bird can’t fly. Examples???
Birds usually molt during late summer after nesting season before migration.

7. Skeleton Hollow bones that have struts.
Long neck with a atlas and axis vertebrae that rotate the bird’s head.
Sternum or breastbone that is fused to the clavicle.

8. Metabolism
All birds undergo endothermy, which is the maintanance of a constant body temperature.
Birds need a high metabolism in order to sustain flight.
A bird’s body temperature is between 104 –107 F.
This is one of many reasons why human can’t fly

9. Digestive System
Enters an elastic esophagus  crop  stomach ( proventriculus & gizzard)  intestine  cloaca
Most birds swallow gravel for their gizzard to grind food.
Birds of prey form pellets of indigestible materials that are regergetated as owl pellets.

10. Respiratory System 2 cycle system
Mouth  trachea  syrinx  brochii (2)  lungs  posterior air sac {1st cycle is complete}
2nd cycle: back to the lungs  anterior air sac  back out through the mouth (exhale)
This allows the bird to have air in its body at all times.

11. Circulatory System How many chambers? Draw the heart Heart Beats
Turkey  93 beats/min
Chicken  250 beats/min
Black-capped chickadee  1,000 beats/min

12. Nervous System Birds have large brains for their size 3 main parts
1. Cerebellum – balance & mov’t
2. Cerebum – controls all intelligence
3. Optic lobes – for vision
Rods  for dim vision
Cones  for color vision

13. Reproductive System
The male bird produces sperm in the 2 testes, which travels through the vas deferens to be released.
The female bird usually have 1 ovary on the left side, which releases an egg into the oviduct where it is fertilized.

14. The eggs are then incubated with a featherless patch of skin on their abdomen called a brood patch.
Can you name some different types of nests?
Some birds lay their eggs in others nest.
Cuckoo, starling, & cowbird

15. Hatchlings (2 types) 2. Altricial Birds born naked & helpless
1. Precocial
Birds born with down feathers
Ex. Ducks, quail, geese (water birds)
2. Altricial
Birds born naked & helpless
Demand a lot of food
Ex. Most birds
Which one of these is incubated longer?

16. Migration Greatest adventure & risk for a bird. Do all birds migrate?
Many birds migrate back to the same spot each year.
Several male bird species undergo courtships to display their colors and dominance. This is called a lek. Examples?

17. Ratites  Flightless Birds
1. Ostrich
Africa, 2 toes, very fast (35 mph)
2. Rhea
S. America, 3 toes, smaller than the ostrich
3. Emu
Australia

18. 4. Cassowary
Australia, very tem0permental bird
Known to attack humans with long dagger-like claws
5. Kiwi
New Zealand, smallest ratite
Lays a 5 in. egg that is about 1/3 its body weight.

19. Penguins are also flightless, but they had flying ancestors that lost the use of their wings; flight was no longer useful to their mode of life.
Binocular vision
Overlapping vision
Owls have the best binocular vision (flat face)
Sparrows have very little; eyes near their sides
Woodcocks have little if any.