1. KINGDOM ANIMALIA Phylum Chordata Subphylum Vertebrata Class Mammalia

2. Vertebrate Classes

3. Characteristics of Mammals
Hair – composed of keratin for insulation, sensation, appearance, and protection. (other keratinized structures – horns, antlers, etc.)
Mammary Glands – modified sweat gland that, in females, produce milk to nourish their offspring.
3 Middle Ear Bones – malleus, incus, and stapes (hammer, anvil, and stirrup); the first two derived from the ancestral jaw.

4. Other mammal structures
Question
Hair is made out of a protein called
lactose.
keratin.
mammalin.
hemoglobin.
Other mammal structures
made of keratin:

5. Characteristics of Mammals
Highly differentiated teeth
2 sets of teeth
Single lower jaw bone
4 chambered heart
Secondary palate
Muscular diaphragm
Highly developed brain
Endothermy and homeothermy
Separate sexes (XX or XY)
Internal fertilization

6. Question Which of the following is NOT a characteristic of mammals?
4-chambered heart
Internal fertilization
Muscular diaphragm
Multiple lower jaw bones
Although mammals have only one lower jaw bone, they have three inner ear bones. The three mammalian ear bones were originally jaw bones, but have changed in size and function.  The reduction in number of lower jaw bones is easily traced through fish, amphibian and reptile. 

7. Mammalian Teeth Heterodont teeth – different types of teeth
2 sets of teeth - Diphyodont
Dental Formula – shorthand way of describing teeth
Diastema – toothless gap
Carnassial apparatus
Incisors chisel shaped for gnawing and nipping (1 root)
Canines long conical for catching, killing, and tearing (1 root)
Premolars and Molars broad for chewing (1-2 or 2-3 roots)

8. Question Mammals have “diphyodont” teeth. What does this mean?
They have two sets of teeth.
They have different types of teeth.
They have a toothless gap in their teeth.
They have more than two sets of teeth.
All mammals are born with a temporary
set of teeth that are lost and replaced by a
permanent set as they mature into adults.

9. Mammalian Glands
Glands are an epidermal tissue that secrete substances.
Sudoriferous – sweat for evaporative cooling and elimination of waste.
Sebaceous – secrete oil for waterproofing of hair.
Scent – secrete pheromones for defense, sex recognition, and territorial behavior.

10. Cold Weather Adaptations
Endothermy – the generation of internal heat
Homeothermy – the maintenance of constant temperature
Winter Sleep – the organism is less active, alert, and easily aroused (Bears and raccoons)
Hibernation – the organism slows metabolism, and heart and respiratory rates (monotremes, and some insectivora, rodentia, and chiroptera)

11. Bears hibernate in the winter.
Question
True or False
Bears hibernate in the winter.
Hibernation involves a slowing of heartbeat and respiration and usually a significant drop in body temperature. In contrast, bears enter a state of sedation referred to as “torpor.” Their metabolism slows down during the long winter sleep so that they do not need to eat, drink, urinate, or defecate until they emerge from their dens.

12. Mammalian Classification
Prototheria (Monotremes): oviparous (egg-laying).
Metatheria (Marsupials): viviparous with a short gestation, further development occurring in a pouch.
Eutheria (Placentals): viviparous with a long gestation.

13. Question Which group of mammals is oviparous? Monotremes Marsupials
Placentals
All of the above
“Monotreme” is from the Greek “monos” meaning “single” & “trema” meaning “hole.” This refers to the fact that they possess a cloaca, through which a single egg is laid.

14. Terrestrial Placental Orders
Order Artiodactyla
Order Perissodactyla
Order Carnivora
Order Insectivora
Order Lagomorpha
Order Rodentia
Order Chiroptera
Order Primates
Order Xenartha
Order Proboscidea

15. Order Artiodactyla (Even-Toed Ungulates)
Specialized for distance running with long hoofed legs
Number of teeth is variable but they all have a diastema
Chambered stomachs for microorganisms to decompose cellulose into digestible components
Males often sport antlers or horns
Include deer, sheep, antelope, cows, hippopotamuses, camels, & giraffes

16. Order Perissodactyla (Odd-Toed Ungulates)
Simple stomachs
Middle toe is larger than the others
Horses, Rhinos, Tapirs

17. Order Carnivora
Although not all current carnivora are carnivorous, the ancestors were meat eaters
Recognizable carnassial apparatus for shearing meat and tendons
Keen senses and large brains
3 upper and 3 lower incisors
Dogs, cats, bears, raccoons, mustelids

18. Order Insectivora
Third largest order of mammals and possibly the most primitive group of placental mammals
Insectivorous
Taxonomy is currently being revised
Moles, shrews, and hedgehogs

19. Order Lagomorpha Resemble large rodents with short tails
Flaps of skin can close behind the incisors so that chewing can happen with the mouth closed
Flaps of skin can also close the nostrils
2 upper incisors, one behind the other
Produce two types of fecal material, one that is wet and eaten again for further nutrient absorption, and one that is dry and discarded
Rabbits

20. Order Rodentia Largest mammalian order (40% of species)
Individual upper and lower incisors that are rootless and grow throughout life for a gnawing life style
Squirrels, chipmunks, rats, mice, beavers, and porcupines

21. Order Chiroptera Second largest mammalian order (20% of species)
Bat wings are modified forelimbs with the flight surface covered with skin and supported by four fingers
The flight membrane usually extends down the sides of the body and attaches to the hind legs
Bats

22. Order Primates Originally adapted as tree-dwellers
Shortened nose and forwardly directed eyes, associated with stereoscopic vision
Most live in the tropics or subtropics
Lemurs, Tarsiers, Monkeys, Gibbons, and Apes

23. Order Primates

24. Order Xenarthra Incisors and canines absent
Xenarthra means "strange joints", and was chosen because their vertebral joints are unlike those of any other mammals
Placed in a separate group from all other eutherians
Anteaters, sloths, and armadillos

25. Order Proboscidea
Have a long, muscular trunk that functions almost as a fifth limb
Have a pair of huge tusks derived from upper incisors
Their cheek teeth are uniquely adapted to their highly abrasive diet
Elephants

26. Order Proboscidea

27. Question
Which group of placental mammals has a name that literally means “strange joints?”
Primates
Xenarthra
Proboscidea
Artiodactyla
Their vertebral joints have extra articulations and are unlike those of any other mammals.

28. Aquatic Placental Orders
Order Carnivora – Otters, Weasels, Seals, Walruses, Sea Lions
Order Cetacea – Whales, Dolphins, Porpoises
Order Sirenia – Manatees, Sea Cows