Birds

1. Birds

2. Kingdom • Kingdom= Animalia • Phylum= Chordate • Class= Aves

3. Birds • Ornithology is the study of birds. • Birds belong to the class Aves • Birds 1st appeared on the earth about 150 million years ago. • There are about 10,000 species of birds in the world. • Birds developed from reptiles. • Archeopteryx is the earliest fossil of a bird.

4. Fossil evidence shows that birds evolved from the same line as crocodiles and dinosaurs. Reptiles and Birds • Archaeopteryx was an ancient bird with a reptile-like tail, clawed fingers on the wings, teeth, and a body covered with feathers. Birds Evolution of Birds Archaeopteryx

5. Archaeopteryx had characteristics of both reptiles and birds. • There are 8 main characterisitcs of birds: • Feathers: All bird have feathers. They are made of keratin. Feathers are essential for flight. Feathers insulate a bird’s body against heat loss.

6. Reptiles and Birds Characteristics of Birds • Birds have feathers, wings, lightweight bones, and other adaptations that allow for flight.

7. Reptiles and Birds Birds Endotherms • Birds are endotherms, which means they generate body heat internally by their own metabolism. • A high body temperature enables the cells in a bird’s flight muscles to use large amounts of ATP needed for rapid muscle contraction during flight.

8. Reptiles and Birds Birds Feathers • Birds are the only living animals to have feathers. • Feathers have two main functions: • Flight • Insulation

9. Wings: Their forelimbs are modified into a pair of wings. Feathers cover most of the surface of the wing. • Lightweight skeleton: most bones are thin walled and hollow. Aids in flight. • Endothermic (warm-blooded) have a rapid metabolism needed for flight. Body temperature is 104-106 F.

10. Reptiles and Birds Birds

11. Reptiles and Birds Birds • Feathers that cover the body, wings, and tail of a bird are called contour feathers. • Contour feathers consist of a shaft with barbs that and are held together by hooks. • Down feathers are soft feathers located beneath the contour feathers. • The preen gland secretes oil that adds a waterproof coating to the feathers.

12. Reptiles and Birds Lightweight Bones • A strong, lightweight skeleton allows birds to fly. • The bones of birds are unique because they contain cavities of air. • Large, powerful muscles attach to the sternum and keel.

13. Reptiles and Birds

14. Some birds do not fly • Ostrich –Africa • Rhea- South America • Kiwi- New Zealand • Cassowary Australia • Penguin-Antartica • They have survived because of other adaptations. ie. Penguin location, Ostrich run fast and have powerful legs.

18. Reptiles and Birds • After fertilization, the amniotic egg develops and is encased within a hard shell. Birds Reproduction • All birds have internal fertilization. • Birds incubate the egg or eggs and feed the young after hatching.

19. Oviparity: • All birds lay amniotic eggs encased in a hard shell. Most birds species incubate their eggs in a nest by one or both parents. There are two types of nests. Above ground and on the ground. There are two types of hatchlings: naked and feathered.

20. Reptiles and Birds Amniotic Eggs • The amnion is a membrane that surrounds a developing embryo. • An amniotic egg is covered with a protective shell and has several internal membranes. • The leathery shell protects the internal fluids and embryo.

21. Reptiles and Birds

22. Reproductive System • Male bird sperm is produced in two testes that lie beneath the kidneys • Sperm passes through small tubes called Vasa defrentia into the males cloaca • During mating the male presses his cloaca to the females and releases sperm • Females single ovary releases eggs into a long, funnel-shaped oviduct where they are fertilized by sperm

23. Reproductive System • Reproductive System Cont. • Fertilized eggs move down the oviduct, where they receive protective covering and a shell • Unfertilized egg consists of a nucleus, cytoplasm, and a yoke • When fertilized, the embryo is suspended in albumen, the egg white • The liquid medium is supported by ropelike strands of material called chalaza that are attached to the shell membrane • Female has a shell gland that secretes a protective calcium carbonate shell to surround the egg

24. Development and Behavior

25. Incubation and Development • A female bird usually lays eggs in the nest. One or both parents will incubate or warm the eggs by sitting on them. • The cover them with a thick, featherless patch of skin on their abdomen called a brood patch. • In penguins the male emperor heats the egg by placing it on his webbed feet and enfolding it with his warm abdomen.

26. Incubation and Development • Embryo development begins when the zygote forms a plate of cells on the surface of the yolk. • This plate begins to form the tissues and organs • The membrane produces digestive enzymes that dissolve proteins and lipids in the yolk. • Blood vessels in the yolk sac membrane carry the nutrients to the embryo. • When hatching begins the embryo makes a star-shaped crack in the shell with a scalelike egg tooth. • The chick presses and scrapes the shell until the crack widens enough for the chick to emerge. • The egg tooth, falls off soon after the chick hatches.

27. Incubation and Development • Bird have two contrasting methods for rearing young. • Those that lay many eggs and incubate them for long periods hatch precocial young. • These birds are active as soon as they hatch, they can walk, swim, and feed themselves. For examples ducks and quail. • Birds that lay only a few eggs and hatch quickly produce altrical young. • They depend on both parents for several weeks. For ex. Woodpeckers, hawks, pigeons parrots.

28. Lungs • Unique respiratory system: birds need a lot of oxygen because of their rapid metabolism. Lungs are connected to several sets of air sacs this ensures that oxygen rich air is always in the lungs.

29. Unique respiratory system: birds need a lot of oxygen because of their rapid metabolism. Lungs are connected to several sets of air sacs this ensures that oxygen rich air is always in the lungs.

30. Reptiles and Birds Birds Respiration • Flight muscles use a large amount of oxygen. • When a bird inhales, oxygenated air moves through the trachea into posterior air sacs. • When a bird exhales, deoxygenated air leaves the respiratory system and oxygenated air is sent to the lungs.

31. A bird’s circulatory system helps it maintain high levels of energy by efficient Reptiles and Birds delivery of oxygenated blood to the body. Birds Circulation • Birds have a four-chambered heart.

32. Reptiles and Birds Birds Feeding and Digestion • Birds require large amounts of food to maintain their high metabolic rate. • Many birds have a crop at the base of the esophagus that stores food. • The gizzard contains small stones that crush food the birds have swallowed. Visualizing Feeding and Digestion

33. Reptiles and Birds Birds The Brain and Senses • The cerebellum is large because birds need to coordinate movement and balance during flight. • The cerebrum controls eating, singing, flying, and instinctive behavior.

34. Reptiles and Birds Birds • Birds have excellent vision. • Birds of prey have eyes in the front of the head, which allows them to focus easily. • Some birds have eyes on the sides, enabling them to see nearly 360 degrees. • Birds also have a good sense of hearing.

35. Digestive and Excretory system • Food passes from the mouth cavity straight to the esophagus. • Enlargement of the esophagus called the crop stores and moistens food. • In the first chamber, The proventriculus, gastric fluids begin breaking down the food. • Then passes through the gizzard, a muscular organ that kneads andcrushes the food

36. Excretory System • The avion excretory system is also efficient and light weight • The two kidneys filter a nitrogenous waste called uric acid from the blood •  highly concentrated uric acid travels by ducts called ureters to the cloaca, where along with undigested matter from the intestines, it is excreted in a semisolid, usually white mass

37. Respiratory System • Air enters through paired nostrils at base of beakDown trachea past syrinx, or song boxenters two primary bronchiito lungs75% bypasses the lungs and flows directly to posterior to sacssacs connect with air spaces in bones, filling the hollow bones with air • When bird exhales the carbon dioxide-rich air from the lungs, oxygen rich air is forced out of the posterior air sacs into lungs via small air tubes

38. Circulatory System • 4 chambered heart • Right and left sides completely separated • Right side receives deoxygenated blood from the body and pumps it to the lungs • Left side receives deoxygenated blood from the lungs and pumps it to the rest of the body • Has a single aortic arch • Most birds have a rapid heart beat compared to other vertebrates-Hummingbird-600 times a minute Chickadee

39. Reptiles and Birds Birds

40. Reptiles and Birds Birds

41. Beaks Cracker- seed eater Shredder- tears meat Chisel -woodpecker eats insects Probe- Hummingbird eats flower nectar

42. Strainer -eats water plants and animals Spear- spears fish like kingfisher Tweezer- insect eater like warblers Swiss army knife- crow multi-purpose bill. Eats anything

43. Types of feet

44. Wings: Their forelimbs are modified into a pair of wings. Feathers cover most of the surface of the wing. • Lightweight skeleton: most bones are thin walled and hollow. Aids in flight. • Endothermic (warm-blooded) have a rapid metabolism needed for flight. Body temperature is 104-106 F.

45. Grasping

46. Scratching

47. Perching

49. Grasping