MAMMALS
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RESOURCES
3 VIDEO CLIPS
MARSUPIALS
RAT DISSECTION
TEXT Chap 808-829
Class Mammalia kangaroo, bat,
rodents, whales, monkey, giraffe,
man, horse, dog
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Incredible variety in size
1.5 g bat to 100 ton whale
FEATURES
young born live after
gestation in the female
mammary glands (sweat, oil,
pheromone glands)
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lung breathing throughout life
diaphragm separates abdominal and
thoracic cavities
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body covered
with hair
4 chambered
heart
 warm blooded
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7 neck vertebrae in
most species
2 pairs of limbs for
locomotion
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care for few young
internal fertilization
internal development
ORDER MONOTREMATA
Australia, New Guinea, Tasmania
 ie. platypus, echidna
 most reptile like
 lay eggs
 echidna lays egg right into pouch
 don't control body temperature well
 cloaca
 no nipples but have mammary glands
Platypus
echidna (spiny anteater) juvenile
called “puggle”
ORDER
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MARSUPALES
Australia, New Guinea, Tasmania
ie. koala, kangaroo, opossum, wombat
250 species
pouched mammals
Show Koala video here
Koala Bear
Tasmanian Devil
Flying Phalangers
Wombat
opossum
Kangaroo
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young born very helpless after a short
gestation in the female
must crawl to the pouch
nipples in the pouch
Assign reading and text questions
(914-919)
Why are they so isolated in
Australia?
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Continents separated 60 million years
ago and left Australia with no placentals
and only marsupials and monotremes.
marsupials were out competed by
placentals else where in the world
DEFINE convergent evolution
adaptive radiation
PLACENTAL MAMMALS (draw
the placenta)
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14 orders
95% of all mammals
placenta- organ in the uterus that
connects mothers circulatory system to
that of the baby
ORDERS of interest
Ungulates
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-some of the largest mammals
Why? Need a large stomach to digest
coarse food (like the …….)
(cellulose primary component in the diet)
many are built for speed
long light legs, flexible spine, missing
clavicle
leg joints lack rotation, basically pendulum
movement
CLASSIFICATION
(based on feet,
teeth and skulls)
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2 Types
Perrissodactyla- horse, rhino, tapir
(odd toed)
the “Ungulates”
Perissodactyla
the “Ungulates”
Perissodactyla
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Formerly the most successful order
(How do we measure success?)
Number of species, # individuals, land
area, number of habitats
Artiodactyla
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- camel, antelope, hippo, sheep,
cow, pig, giraffe (even toed)
(currently the most successful)
Order Artiodactyla
suborder Suiformes
Order Artiodactyla
suborder Suiformes
Digestion
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Bacteria in the gut aid in digestion,
produces enzymes necessary to break
down cellulose
(chemical digestion)
Repeated chewing of regurgitated veg.
Matter continues mechanical digestion
in some species
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Cows have a RUMEN = a chamber off
the stomach for bacteria
Horse food flows through in 45 hours
Cow’s food flows through in 100 hrs
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More efficient at extracting nutrients
from food may explain this group’s
success!!!!
PIGS (an even toed ungulate)
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Terminology
GiltSowBoarBarrow-
Virgin female
Female that has given birth
Male
Castrated male
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Farrow = giving birth
Gestation 3 m 3w 3d
Female puberty reached in 4-8 months,
breed with in 1 year, heat 1-5 days, 2
½ litters per year
COWS ARE EVIL
(notes in honor of Mr. Bangert)
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-require half the world’s useable land area
-methane gas production “green house
gas”
-poor source of nutrition (high fat, cancer
agents, antibiotics)
-protein available from other sources
-wasteful use of energy and water
ORDER
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RODENTIA
RAT DISSECTION
Rats, mice, porcupine, beaver
Chisel like front teeth
40% of placental mammals
relatively small, adaptive, high
reproductive rate, intelligent
MARINE MAMMALS
(several orders)
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Pinnipedea- seals, sea lions, walrus,
otters
Related to carnivores
Predators
Blubber
Breed on land
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Seal (cat face)
Can’t move back legs
Rear flippers
Hunted for skin
and meat
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sea lion (dog face)
walks like a quadrupeds
tricks in shows
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Walrus
Feeds off inverts
from bottom
Whiskers for feeling
Tusks for digging
Sireniamanatee, dugongs
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Italian for mermaidrelative of the elephant
Highly endangered
Only vegetarian
Skin, oil, meat (like veal)
Front flippers and fluke
Cetaceans- whales, dolphins,
porpoises
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90 species only 5 fresh water
Whales
toothed- predators narwhal, killer,
dolphin
Whales
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baleen – filter feeders
a
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broad flat tails (fluke), front
limbs modified into flippers,
blow hole in nostril
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social animals
songs, pod, breaching
harem- may have 40 females
defense and sex exhausts defending
male in 1-2 years
bachelor groups
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ambergrisindigestible
squid beaks in
sticky mess,
used in
perfumes
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Humpback whale- feed in the arctic
Breed in Hawaii
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Gray whale migration- summer in the
arctic Ocean feeding on schools of krill
Breed in Baja California
EASY
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1. The lower chambers of the heart are called
2. Marsupials and Monotremes composes what % of
mammals?
3. Atridactyls are even or odd toed?
4. Gland in the region of the neck of a rat:
5. Organ that links baby to material circulatory
system.
6. A cloaca would be found in what mammal?
7. Name the sieve like structure in some whales.
8. Marsupials are found mostly where?
EASY
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1. The lower chambers of the heart are called
ventricle
2. Marsupials and Monotremes composes what 5% of
mammals?
3. Atridactyls are even or odd toed?
4. Gland in the region of the neck of a rat: thymus
5. Organ that links baby to material circulatory
system. placenta
6. A cloaca would be found in what mammal?
Monotremes platypus, echidna
7. Name the sieve like structure in some whales.
baleen
8. Marsupials are found mostly where? Australia,New
Guinea, New Zealand
MEDIUM
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1. Name 5 marsupials.
2. I’m a pinneped with great legs and a dog
like face.
3. Name two organs in the thoracic cavity.
4. Another name for vibrissae is
5. If you remove the organs in the abdominal
cavity, what organs are along the back body
wall?
6. Blood enters the heart from the body in
what chamber?
7. What structures enter and exit the
stomach?
MEDIUM
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1. Name 5 marsupials. Koala, Taz. Kangaroo
2. I’m a pinneped with great legs and a dog
like face. Sea lion
3. Name two organs in the thoracic cavity.
Heart, lungs
4. Another name for vibrissae is whiskers
5. If you remove the organs in the abdominal
cavity, what organs are along the back body
wall? kidneys
6. Blood enters the heart from the body in
what chamber? Right atrium
7. What structures enter and exit the
stomach? Esophagus ,intestines
DIFFICULT
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1. Explain the distribution of marsupials.
2. Explain embryonic diapause. What is it’s
adaptive value?
3. Name the 2 blood vessels that carry blood
to the heart from the body.
4. Birthing a pig is called ________ and the
mom is called a _______
5. List 3 reasons why “cows are evil”.
6. Describe the first mammal.
DIFFICULT
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1. Explain the distribution of marsupials.
Australian continent drifts away with no
placental mammals to compete with the
marsupials. They survive and diversify.
2. Explain embryonic diapause. What is it’s
adaptive value? Embryo in uterus will quickly
start to develop if joey in pouch dies
3. Name the 2 blood vessels that carry blood
to the heart from the body. Anterior and
posterior vena cava superior and inferior vc
DIFFICULT
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4. Birthing a pig is called __farrow______ and
the mom is called a _sow______
5. List 3 reasons why “cows are evil”.
Require much land space to raise
Poor source of protein (high fat and
cholesterol)
High antibiotic use, possible cancers from high
red meat diet.
6. Describe the first mammal. Legs out 90
degrees, reptile like, clumzy, insectivore
STUDY GUIDE FOR MAMMALS
(a copy will be handed out)
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1. Heart anatomy and blood flow
2. Rat anatomy from dissection lab
3. History and behavior of rats from lab
4. Characteristics of mammals
5. Origin and structure of the placenta
6. Diagram the placenta
7. Characterize specific orders. Monotremes, Marsupials,
Ungulates, Aquatic Mammals
8. Explain why some people consider “cows to be evil”.
9. Explain distribution of marsupials
10. Explain origin of mammals.
11. Trace the digestive system.
12.Know the function of these systems: circulatory, respiratory,
digestive, reproductive, skeletal
13. Notes from text reading