Download Chapter 15—Birds and Mammals

Chapter 15—Birds and
Mammals
Or Hair, Feathers and Flight
I. Characteristics of Birds
A. Very diverse group of
animals—many types and
habitats
B. Varied diets between
species—herbivores,
carnivores, scavengers
Parakeet—
herbivore
Vulturescavenger
Red-tailed hawk—predator
C.Lay eggs, have scales and
feathers—feathers are
unique to birds
D.Endotherms—warmblooded animals; birds have
a steady body temperature
E. Bird Eggs
1.Amniotic eggs like the type
reptiles have
2.Egg is fertilized internally
before the shell forms
3.The hard shell protects the
developing embryo
Membrane
Embryo
Shell
Yolk sac
Allantois—holds
wastes
II. Bird Body Systems
A. Digestive system
1. Birds need large amounts
of high energy food
2. Complete digestion can
take less than an hour
(humans can take more
than a day)
3. Food is stored in an organ called
the crop before it goes to the
stomach, then the gizzard that
physically breaks down the food
4. Nutrients are then absorbed into
the bloodstream from the
intestine
B.Respiratory system
1.2 lungs and air sacs that
extend into other parts of
the body including some
bones
2.Get oxygen from the air as
they inhale and exhale—
unique to birds
C.Closed circulatory system
1.Arteries carry blood from
heart, to capillaries where
oxygen and nutrients are
delivered; the blood then
returns to the heart through
veins
2.Four-chambered heart
a.2 chambers collect blood, 2
chambers pump blood
b.Relatively 4 times the size
of a human heart
c.Very high rate keeps body
supplied with oxygen-rich
blood
Hummingbird—heart can beat up to 1,000 times a minute—the average
human heart rate is about 80 times a minute
III. Flight Adaptations
A. Lightweight, but strong
skeleton
B. Bones are hollow, but often
fused together and have
cross braces
C.Large breastbone supports
strong chest muscles that
beat the wings
D.Last bones of the spine are
attached to the tail feathers
E. Feathers
• Contour feathers give bird its
shape, and allow the bird to
steer
• Down feathers—soft and fluffy
act as an insulation layer to keep
birds warm
• An oil gland is used for
preening—the oil conditions the
feathers and keeps them
waterproof
F.Wings
• Attached to powerful chest
muscles
• Provide the thrust and lift
necessary for flight
IV. Characteristics of Mammals
A. Vertebrates
B. Endothermic—warmblooded animals
C.Skin and Glands
1.Skin produces hair and can
be adapted to produce horns,
claws, nails, or hooves in
some species
2.The skin contains various
glands, including sweat
glands and mammary glands
3.Mammary glands produce
milk in female mammals, this
is where we get the name
mammal
4.Many species also have
scent glands used for
attracting a mate, marking
territory, or as a type of
defense
D.Hair
1.At some point in their lives all
mammals have hair
2.Hair can be adapted to
become fur that helps keep
an animal warm
3.Whiskers are specialized
hairs that help many
mammals sense their
environment
Whiskers are about
twice as thick as normal
hairs.
Scientific name
for whiskers
E. Teeth
1.Many types of teeth exist in
mammals
2.The type of teeth vary by
what the diet of the mammal
is
3.Four types of teeth—incisors,
canines, premolars, and
molars
4.Carnivores will have only
incisors and canines
5.Herbivores have only
premolars and molars
6.Omnivores like humans
and bears have all 4 types
F. Body systems
1.Systems vary between
mammals, adapted to each
species typical type of activity
2.Closed circulatory system
including 4-chambered heart
3.Lungs made of millions of
tiny sacs that allow them to
hold more air
Human Brain
Human Heart
4. Mammals have highly developed
brains, especially in the areas of
learning, remembering and
problem-solving
5. Digestive systems vary
depending on diet—herbivores
can have 4-chambered
stomachs because plants take
longer to digest
G.Reproduction
1.Reproduction is sexual
2.Most mammals give live
birth
H.Mammals care for their young
1.This is one of the defining
characteristics of mammals
2.Young mammals develop at
different rates, but many are
not capable of taking care of
themselves at birth