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MAMMALS
Endothermic vertebrate with hairWarm-bloodedPermits high level of activity at night and
year-round (regardless of outside temperature)
Females have mammary glands Function: make/secrete milk for young
About 5000 species Ex: cats, dogs, humans, dolphins,
elephants, kangaroo, whale, bat, rabbit, beaver, wolf, seal, mouse, platypus, chimpanzee, tiger
GENERAL CHARACTERISTICS
High degree of parental care Body covered by hair
In some, hair is reduced in size – like humans
All have an integument (external covering) Contains: sweat, scent, sebaceous and
mammary glands
GENERAL CHARACTERISTICS
Breathe using lungs Excrete using kidneys Separate sexes Young nourished by milk (made by
the mammary glands) Many have territories
These are areas from which individuals of the same species will reside
Will often resort to violence to protect these territories
GENERAL CHARACTERISTICS
Rodents Ex: mice, squirrels, rats, woodchucksHave two razor sharp incisors for
gnawing Lagomorpha
Ex: rabbits, hares, pikasAll are herbivores
Hominids Ex: humans, gorilla, orangutan, chimps
Insectivora Ex: moles, shrewsDiet consists of insects
CLASSIFICATION
Carnivora Ex: weasels, seals, walruses, dogs,
wolves, cats, bearsHighly predatory animals, Contain teeth for tearing flesh
Proboscidea Ex: elephantsLargest of living land animals
CLASSIFICATION
Perissodactyla Ex: horses, donkeys, zebras, rhinosOften referred to as ungulates or the
hoofed animals Cetacea
Ex: dolphins, whales, porpoisesLimbs are modified into flippersLive in aquatic environments only
CLASSIFICATION
Skeleton Skeletal/bone make-up allows for:
High-speed running Swimming climbing trees Movement of digits (fingers/toes) to help
grasp objectsJoints allow for a greater range of
motion
MOVEMENT AND RESPONSE
Hair:Has become a modified sense
“organ”Purpose of hair:
Spines of porcupines—protectionHair of most animals—insulationVibrissae (whiskers)—provide
tactile sense Slightest movement indicates minimal
space available (cat/dog)
MOVEMENT AND RESPONSE
Moveable eyelids Fleshy external ears Well-developed brain
The largest brain in animal kingdomCerebrum—processes info for thinking
and learningHigh evolved brain allows for highly
developed memory and capacity to learn topics/developmental milestones quicker
MOVEMENT AND RESPONSE
Highly elaborate sensory organsProvide mammals with a high level of
environmental awareness and responsiveness
Senses: taste, smell, hearing, sightMost have great eyesight Many can’t see colorMany will use echolocation to
communicate and/or navigate Ex: Bats, dolphins
MOVEMENT AND RESPONSE
TeethMammalian teeth are both more
complicated and more efficient than in other vertebrates
Mammals are heterodonts (some of our teeth are different)
Specialized for variety of functions: Includes: grind, stab, scissor, dig, chisel,
sieve and lift (elephants tusks)
DIGESTION AND EATING
Teeth, cont.Teeth in mammals come in four different
sorts: Incisors, Canines, Premolars and Molars. Not all mammals have all
Use this variety to eat a wide variety of food
Most placental mammals have between 20 and 40 teeth, while most marsupials have 30 to 50.
As a general rule animals that feed on insects have more teeth than either herbivores or the larger carnivores.
DIGESTION AND EATING
Contain a secondary palateSeparates air passageway from the
food passageway Allows mammals to hold (and
partially break down food) in mouths without interrupting breathing
DIGESTION AND EATING
Have many feeding adaptations Insectivores are often smallHerbivores have two groups
Groups: browsers and grazers Have large molars adapted for grinding
Carnivores have large canines Adapted for ripping/tearing meat
Other adaptations:Ruminants (cattle, bison, goats) have a
four-chambered stomach
DIGESTION AND EATING
Energy and WastesRequire much energy to keep a
constant body tempProduce a variety of waste products
(uric acid, urine, feces, etc) Digestive tract
If mammals eats only plants, longer digestive tract Why? takes longer to digest
plants/celluloseIf eat only meat, shorter digestive tract
DIGESTION AND EATING
Require a large amount of oxygen for respiration
2 organ adaptations for this:Diaphragm:
Muscle that contracts and therefore, allows for more rapid/controlled breathing
Four-chambered heart: Separates blood into
oxygen-rich/oxygen-poor
RESPIRATION
All have internal fertilization All have mammary glands 3 groups of Mammal life cycles:
1. Placental:2. Marsupials:3. Monotremes:
LIFE CYCLE
Placental:Develop inside mother’s body 95% of mammals are thisPlacenta—organ which allows for
nutrients, oxygen, carbon dioxide and wastes to be exchanged
LIFE CYCLE
Placental, cont.:Gestation period—time that
embryo stays in the mother’s body Humans: 9 months, Elephants:
27 months, Mice: 21 daysMammary gland—young continue
to feed by sucklingEx: humans, dolphin, elephant,
most mammals
LIFE CYCLE
Marsupials:Give birth to small, immature young that
develop in a mother’s external sac (kangaroo)
Mothers can move around and look for food while baby develops in the pouch
Ex: kangaroo, koala, panda Monotremes:
Mammals that give birth by laying eggs Incubate using her heatEx: platypus
LIFE CYCLE