18.1 birds

18.1 Birds
Page 367

Bird Characteristics
Vertebrates
ENDOTHERMs
Organisms with a constant internal body temp.
Cells of body stay warm & work normally all the time
Only animals w/ feathers
Beaks, not teeth
Have wings
*Not all can fly!
Lay eggs w/ shells

Origin of Birds
Earliest fossil of a bird found in 1861
Like a reptile: scales, jaws with teeth, claws on front limbs
Imprint of feathers
Evidence birds evolved from reptiles

Diversity of BIRDS
Over 9,000 species of birds
4 Groups
Birds of prey
Perching birds
Water birds
Flightless birds
Each bird is adapted to eating a certain kind of food & living in a certain habitat
Lifestyle reflected in its:
Beak
Wings
Feet

Birds of Prey
Eat mammals, fish, other birds
Sharp, hooked beaks to tear flesh
Claws for grasping
Examples:
Eagles
Hawks
Owls
Falcons
Vultures
Osprey

Perching Birds
Insect eaters
Long, pointed beaks work like tweezers
Used as drills for boring into wood in search of insects
Examples:
Woodpeckers
Swifts
SEED EATERS
Thick, strong beak for cracking seeds
Examples: cardinal, blue jay, robin

Flightless Birds
Lost ability to fly
Lifestyle makes flight unnecessary
Many are fast runners
Examples:
Ostrich
Rhea
Penguin

Water Birds
Have a variety of beaks, wings, and feet
Many have webbed feet (swimming)
Some have long legs for wading
Some have long wings
Examples:
Flamingos
Storks
Swans

Flight Adaptations
Streamlined
Lightweight bones
Require large amounts of fuel
Bird’s body releases energy stored in food quickly & efficiently
Cells do this at much quicker rate than other animals
This process creates heat (ENDOTHERMS)

Flight Adaptations
Vision
Avoid flying into things
See food from far away
Large eyes
Sharp vision
Muscles
Flying requires great muscular effort
Powerful flight muscles attached to large breastbone

Flight Adaptations
Bones
Hollow, lightweight bones
Cross-supports inside bones for support

Bird skeleton

Flight Adaptations
Digestive System
Must take in large and steady amount of food
High Energy needs
CROP stores the food and releases it in steady stream for digestion
GIZARD grinds up food for easy digestion

Bird digestion system

Flight Adaptations
Air Supply
Special breathing system – provide blood with blood
In addition to lungs, birds have air sacks to increase amount of oxygen
Heart
4 chambered: keeps low and high oxygen blood separate
Provides flight muscles with oxygen

Feathers
Needed to fly
Most feathers: CONTOUR feathers
Interlocking barbs
DOWN feathers: fluffier, traps layer of air next to body – heat, insulation

Physics of flight
Flying made easer b/c wings provide LIFT
Wing shape is key
Upper surface of wing is rounded
Air takes longer to go around curved upper part than bottom flat surface

Physics of flight
Air takes longer to go around curved upper part than bottom flat surface
Air above wing must move faster to cover distance in same amount of time
The different air speed above & below creates difference in air pressure
Pressure under wing HIGHER
Thus, more force pushing UP (under wing) than DOWN (on top of wing)
Results in lift

migration
Why? Cold & shortage of food
MIGRATE: move to different place during part of every year
Many travel same routes every year

reproduction
Similar to reptiles
Eggs fertilized in female body
Eggs must stay warm – have to INCUBATE
Many species - male & female take turns
one finds food, one incubates
Attachment b/n male & female called Pair-Bonds

Bird eggs
Hard shell
Keeps embryo from being crushed during incubation
Bird egg contains:
ALBUMEN & YOLK – provides food for embryo

18.1 birds

by Colfax

Accessibility

Categories

Upload Details

Usage Rights

Statistics

18.1 birds Presentation Transcript