MammalsKingdom Animalia---Phylum Chordata------Subphylum Vertebrata---------Class Mammalia

What do you get when you cross an elephant with a fish?

swimming trunks

Characteristics

1. Hair (some marine mammals have very little)

2. Specialized Teeth3. Endothermic (warm-blooded)4. Mammary Glands5. Placenta (most)6. Diaphragm - muscle that aids breathing

What kind of animal is this?

Evolution of MammalsMammals did not come to dominate until the CENOZOIC ERA, after the dinosaurs became extinct

Early mammals were probably rodent-like and nocturnal

How do mammals stay warm?

Hair insulates most mammals

Some marine mammals have a layer of subcutaneous fat (blubber)

What is the placenta?Attached to the wall of the uterus , it provides the fetus with nourishment.

The Birth of a Giraffe

What are mammary glands?Only found in mammals, produce milk to feed young.

How the Diaphragm Works

Specialized Teeth●Incisors – biting●Canines - stabbing, holding●molars - crushing, grinding

Different types of mammals have different types of teeth - depending on their diet

Predators have large canines Herbivores have large flat molars

The canines of predators are very large and sharp, used for tearing flesh

DigestionMammals have diverse diets. Herbivores often have an extra stomach chamber called a RUMEN to help them digest plants

This chamber holds bacteria that can digest plant material

CirculationMammals have a 4 – chambered heart and double loop circulation.

What other animals have a double loop?

MovementMammals are a diverse group. Some…

●Run●Climb●Dig●Fly●Swim

Legs are adapted to a particular job

Mammals are TETRAPODS, meaning they have four limbs. These limbs can be adapted to different functions, such as the wings of bats or the flippers of whales.

An animal that is BIPEDAL walks on two legs.

Whales do not have hind limbs, but they do have VESTIGIAL pelvic bones.

Quick Check

1. What attaches to the uterus wall and nourishes an embryo? _____________________

2. What muscles helps mammals breathe? _______

3. Which type of tooth is used for grinding? _____4. What part of a cow helps them digest plants? _____

5. The structure of the jaw and teeth can give you information about about a mammal’s: a. habitat b. age c. diet

6. Mammals have [ double / single ] loop circulation.7. Diversity refers to a. different kinds b. the way animals evolved

Reproduction

Most mammals give birth to live young. There are two groups that are exceptions…

1.Monotremes (lay eggs)2.Marsupials (develop young in a pouch)

Order Monotremata●Egg laying mammals found only in Australia●Have reptilian characteristics

(cloaca & egg laying)●Have mammalian features

(hair, mammary gland)

Examples: Duck Billed Platypus Echidna (Spiny Anteater)

http://www.youtube.com/watch?v=QNoQvjlmGdk

Order Marsupiala●Mammals bear their young in an immature

state, babies develop in a pouch●Majority are found on Australia, opossums

are found on other continents

Marsupial Examples

Can you name these animals?

Kangaroo Birth

Placental MammalsPlacental Mammals have a gestation period (length of time in uterus)

Placenta

Watch the birth of Mia’s First Puppy!

Domesticated animals have been kept and bred by people - cows, dogs, pigs, horses..etc

Biogeography of Mammals

Why do animals on different continents look alike?

Flying Squirrel and Sugar Glider

Answer:

Convergent Evolution

Unrelated species are adapted to similar environments and similar NICHES

Austin’s Sugar Glider

Quick Check

1. Mammals that lay eggs are called: ____________

2. Mammals that carry young in a pouch are called: _________________

3. The length of time a mammal grows in the uterus is called: __________

4. This structure attaches the fetus to the uterus and provides nourishment: _____

5. Name a mammal that has a cloaca. _____

6. Why do unrelated animals resemble each other? __________________ evolution