Download internal body temperature

• Reptile-like animals that have maintained a constant
internal body temperature
• Two legs covered with scales that are used for
walking or perching
• Front limbs modified
into wings
• Outer covering of feathers: made
mostly of proteins and developed from
pits in the birds’ skin
• Contour feathers
• Down feathers
• Powder down feathers
• A dinosaur with feathers
• Archaeopteryx: first fossil
found of an early bird-like
animal
• Looked like a small, running
dinosaur with well-developed
feathers
• Unlike modern birds, it
had teeth, a bony tail,
and toes and claws on its
wings
• It is a transitional species
between dinosaurs and
birds
Adaptations for Flight
• Highly efficient: digestive system,
respiratory system, circulatory system
• Aerodynamic feathers and wings
• Strong chest muscles
• Endotherm: animal that
generates its own body
heat and controls its body
temperature from within
• Include birds, mammals
and some other animals
• High rate of metabolism
compared to ectotherms
• Metabolism produces heat
• A bird’s feather’s insulate
its body enough to
conserve most of its
metabolic energy
• Any body heat that a bird
loses must be regained by
eating food
• The more a bird eats, the
more heat energy its
metabolism can generate
• Small birds must eat more,
relative to their body size
• Birds beaks, or bills, are adapted
to the food that they eat
• Crop: structure at the lower end
of the esophagus in which food
is stored and moistened
• Gizzard: a muscular organ that
helps in the mechanical
breakdown of food
• Air sacs: one of several sacs attached to a bird’s lungs
into which air moves when a bird inhales; allows for
the one-way flow through the respiratory system
• Advantages:
– The one-way flow of oxygen-rich air helps birds maintain
their high metabolic rate
– Enables birds to fly at high altitudes where there is little
oxygen in the atmosphere
• 4 chambered hearts and 2
separate circulatory loops
• 2 ventricles
• Complete separation of oxygenrich and oxygen-poor blood
• This double-loop system ensures
that oxygen collected by the
lungs
is
distributed to the body tissue
with maximum efficiency
• Similar to that of many
reptiles
• Nitrogenous wastes are
removed from the blood
by the kidneys and
converted into uric acid
• Uric acid is sent to the
cloaca
• Water is reabsorbed into
the body
• Uric acid crystals leaving
the body are in a white,
pasty form
• Well-developed sense organs to coordinate the movements
required for flight
• Brain can quickly interpret and respond to many incoming
signals
• Brain is large for its body
• Well developed eyes
• Can hear well
• Sense of taste and smell are not well-developed; the olfactory
bulbs in the brain are small
• Some birds cannot fly
• Walk: ostriches
• Swim: penguins
• Flying birds: many large
bones are fused together
to form a sturdy frame for
flight
• Both male and female
reproductive tracts open into
the cloaca
• The sex organs are internal and
often shrink inside when birds
are not breeding
• Amniotic eggs: similar to
reptilian eggs but have hard
outer shells
•There are nearly 30 orders of birds
•Some of the better known groups:
• Perching birds:
Passerines (includes
songbirds such as larks,
sparrows and finches)
• Pelicans and their
relatives
• Birds of prey
• Parrots
• Cavity-nesting birds
• Herons and their
relatives
• Ostriches and their
relatives
• Birds interact with the natural ecosystems and
human society in many ways
• Disperse seeds, pollinate plants
• Migrate long distances
• Serve as indicators of environmental health
The earliest known bird,
Archaeopteryx
lithographica, lived about
150 million years ago
during the Jurassic Period.
Diversity Birds
The world’s only
wingless bird is the
kiwi of New Zealand.
A bird’s
feathers weigh
more than its
skeleton does.
Some of the 30 classes of birds:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
Waterfowl (ducks, geese, swans)
Perching birds, aka songbirds
(sparrows, crows, cardinals)
Gamebirds (chickens, turkeys,
peacocks, pheasants)
Woodpeckers & relatives
The strike
of the eagle
Hummingbirds & swifts
talon has
Birds of prey (condors,
twice the
hawks, falcons, eagles)
power of a
Owls
rifle bullet.
Pigeons & doves
Herons, storks, & relatives
Parrots (macaws, lovebirds, cockatoos)
Pelicans & relatives (cormorants,
frigatebirds)
Bald eagles have an
Ostriches
average wingspan
Flamingos
of 6 to 8 feet.
Penguins
The arctic
tern makes the
longest migration
each year, flying
20,000 to 25,000
miles each year
from the Arctic to
the Antarctic and
back again.
Birds


Vertebrates
Common characteristics


A hawk can
see a mouse
from a height
of one mile.

Some parrots
must fly over
500 miles a
day to forage
for food.
The only known
poisonous bird
is the pitohui
from Papua,
New Guinea





Beak with no teeth
Bipedal
Forelimbs modified
into wings
Body covered with
feathers
Endothermic
Highly efficient
respiratory system
Hard-shelled
amniotic eggs
Extremely diverse!
The largest bird
is the ostrich.
Falcons can
dive at over
200 mph.
The Australian
pelican has the
longest beak in
the world—up to
18.5 inches long!
Feathers are
unique to birds
A bird’s heart beats
400 times per
minute while resting
and up to 1000
times per minute
while flying.