Bird Evolution

• The fossil record indicates birds evolved from Theropoda (Coelusauria: Tyranosaurus, Ornitho mimosaur and Maniraptor) during the Jurassic period, around 150–200 million years ago (Ma), and the earliest known bird is the Late Jurassic Archaopteryx lithographica, around 150–145 Ma.

Class Aves• Feathers (the

evagination of skin)• No teeth• Flexible long neck

with one condylus occipital

• Scales on legs• Bones with air spaces• Endothermic• Four chambered

heart

Adaptations for Flight

• Honey combed bones– Air cavities– Less weight

Light Weight Skeleton

• Frigate bird• 7 foot wing span• 4 ounce skeleton

Adaptations for Flight

• Enlarged sternum– Flight muscle

attachment

• Long neck– balance

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Pygostyle

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Skull

• Most bones fused• Much lighter than

reptile or mammal skull

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Adaptations for Flight

• Wing– lift

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Adaptations for Flight

• Feathers– Light weight– Strong

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Adaptations for Flight

• Reduce body weight– No teeth– No urinary bladder– No penis– Only one ovary

Beak Adaptations

• Ripping flesh

Beak Adaptations

• Eating seeds

Beak Adaptations

• Sucking nectar from flowers

Beak Adaptations

• Drilling wood

Beak Adaptations

• Catching fish

Beak Adaptations

• Basket-like bill to hold fish caught under water

Beak Adaptations

• Filtering

Digestive System

• Crop– Storage

• Proventriculus– Enzymes

• Gizzard– Grind food

• Cloaca– Waste– Reproduction

Vision

• Up to 8 times keener than human vision

• Each eye moves indendtantly

Respiratory System

• Nine air sacs– Connect to lungs and

centers of bones– Cools the bird

• Fresh air always moving– No dead ends as in

mammals

• Each wing beat moves air– Never run out of air

Benefits of Birds to Man

• Eat insects, rodents and weeds

• Spread seeds for flowers and trees

• Food • Sport• Pets

Fastest Animal

• Peregrine falcon• Strikes prey at 180

mph

Elephant Bird

• Eleven feet tall• 1100 pounds• Largest egg ever• Extinct in late 1600’s

Giant Moa

• New Zealand• Hunted to extinction

about 1600

Hummingbirds

• Fly up, down, left, right, backwards and upside down

• Wings beat 50 -200 times per second

• Heart rate =600 bpm• Eat 2/3 body weight

each day• Nectar, pollen &

insects

Chicks

• Altricial– No feathers– Cannot walk or see– Cannot feed

themselves

Precocial– Down feathers– Can walk and see– Can feed themselves

Archaeopteryx

• 147 MYA• Transitional fossil

– Characteristics of reptiles

– Characteristics of birds

Archeopteryx

• Reptile characteristics– Teeth– Boney tail– Fingers with claws

• Bird characteristics– Feathers– Furcula

Sexual Selection

Bird Classification

• 24-30 orders• 9600 species

Order StruthioniformesRatites in general have many physical characteristics in common. First, the breast muscles are underdeveloped. They do not have keeled sterna. Their wishbones /furcula are almost absent. They have a simplified wing skeletons and musculature. Their legs are stronger .Their tail and flight feathers have retrogressed or have become decorative plumes. They have no feather vanes, which means they do not need to oil their feathers, hence they have no preen gland.

This group is composed of ostriches (Struthionidae), rhea (Rheidae), cassowaries (Casuari-idae), emus (Dromaiidae), and kiwis (Apterygidae).

Order Pelecaniformes• The birds in the Pelecaniformes group are

mostly seabirds, and they are some of the most easily recognized birds in the world. All of the birds in the five families have webbing that connects all four toes

• Most of the other birds in the Pelecaniformes group have bills with serrated edges like the blade of a bread knife. These edges help the birds hold slimy fish. Almost all of the bills have a hook on the end. The hooks help tear apart the birds' prey

• Gular sac

• AnhingidaeFregatidaePelecanidaePhalacrocoracidaeSulidae

Order Ciconiiformes

• Long legs for wading• Long necks• No syrinx

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Order Anseriformes• These birds have compact bodies with

long necks and full webbing between the three forward-pointing toes. The lower bill is flat while the upper is cone-shaped with a sort of nail at the tip. Waterfowl are unable to glide but can fly quickly with their necks outstretched.

• Flat bill• Webbed feet totipalmata

Cygnus olor

Order Falconiformes

• Hooked bill

• AccipitridaePandionidaeFalconidae, Sagittariidae

They differ from other Falconiformes in killing with their beaks instead of their feet. They have a "tooth" on the side of their beak for the purpose.

The beaks of accipitrids are strong, hooked (sometimes very hooked

Order Passeriformes

• Perching foot• Songbirds• 5000 species• Mocking bird• Thrushes• Swallows• Magpie • Crow• Starling• Jays

Order Columbiformes

• Beak with ‘cera’• Short neck• Short legs• Pigeons• Doves

Geopelia striataStreptopelia chinensis

Streptopelia bitorquata

Columba liviaStreptopelia decaocto

Order Strigiformes

• Large eyes• Silent flight• Nocturnal predator• Crossed beak

Order Apodiformes

• Small bird• Rapid wingbeat• Hummingbirds

Order Galliformes

• Chicken like• Strong beaks• Heavy feet• Chicken• Turkey• Pheasants• Quail

Order Charadriiformes

• Short bill• Strong fliers• Shorebirds• Gulls

Order Psittaciformes

• Bent bill• Thick tongue• Hinged and movable

upper beak• Bright colors• Parrots• Parakeets

Order Piciformes

• Two toes forward and two toes backward

• woodpeckers

Order Sphenisciformes

• Webbed feet• Wings as used for

swimming• penquins

The End