1. Mammals

2. Class Mammalia
The name mammalia is derived from mammary glands. These glands produce milk to nourish newborns. Females are the only sex that produce milk, but males also possess these glands. Males just don’t have certain increases of hormones that cause lactation or milk production.

3. Class Mammalia Hair Mammary glands Sweat glands Muscular diaphragm
Endothermic
Four chambered heart
Two sets of teeth
(“baby” and “adult”)
Heterodont teeth
Different shapes and functions

4. Class Mammalia
Additional characteristics (you don’t need to write these down)
Movable eyelids
Two occipital condyles
Three ear bones
Placenta
Except two groups

5. Mammals are endothermic
Mammals are endothermic. They maintain a constant internal body temperature. Hair and a subcutaneous fatty layer helps to maintain warmth, while sweat glands help cool.

6. Movement Backbone that flexes vertically and side to side
Variations in limb bones allow walking, running, climbing, burrowing, hopping, swimming, flying, etc.

7. Basic Mammal

8. Lion

9. Rhinoceros

10. Gorilla

11. Chimpanzee

12. Chimp and Human

13. Bat

14. Same bones, different stance

15. Feeding and Digestion
Mammals may be herbivores, carnivores, omnivores, or filter feeders (baleen whale).
They have specialized teeth
Some mammals that eat plant material have specialized organs to break down plant material including a rumen and cecum
The mammalian digestive system cannot break down plant material on its own. Symbioitic relationships with bacteria and fungi allow plant material to be digested in mammalian organs.

17. Incissors

18. Canine

19. Premolars

20. Molars

21. Grass eaters have different teeth than carnivores

22. SALIVARY GLANDS DIGESTION starts in the MOUTH Image from:

23. BALEEN
Thin keratin plates that hang from the roof of the mouth and screen food from water
Image from:

25. RUMEN In cud chewers like cows, sheep, goats, giraffes
First chamber of stomach containing bacteria to digest plants
Image from:

26. CECUM In non cud chewers like horses, rabbits, rodents, elephants
Small pouch off small intestine containing bacteria to digest plants

27. Human Digestive System

28. Respiration
Mammals have a large diaphragm muscle that when contracted, pulls the bottom of the chest cavity downward, increasing the volume of the chest cavity, allowing a mammal to inhale.
Air is pulled into the chest cavity and lungs when this happens.
When the diaphragm muscle relaxes, the volume of the chest cavity decreases and causes air to be pushed out—exhaling.

29. Human Respiratory system

30. Circulatory system
Mammals have a two loop closed system (pulmonary and systemic) that is very efficient at transporting oxygen to cells and removing carbon dioxide from cells.
4 chambered heart

31. Fig
Fig

32. Mammal Circulation

33. Excretory system
Mammals have highly developed kidneys that help maintain homeostasis.
Kidneys osmoregulate, maintaining water and ion concentrations, as well as removing excess urea or nitrogenous waste from the blood.

34. Human excretory system

35. Nervous system and response
Mammals have the most highly developed brain of any animal. The three main parts of the mammalian brain are the cerebrum (motor movement, sensory info), cerebellum (balance and coordination), and medulla oblongata (involuntary organ control).
Mammals have a cerebral cortex, the center for thinking and complex behaviors
Mammals have exceptional senses such as smell, hearing, and eyesight.

37. Reproduction and development
Distinct separate sexes, sexual reproduction, and internal fertilization.
Most viviparous (duck billed platypus is oviparous and lays eggs)
Young nourished by mother’s milk and usually raised for an extended period of time.

39. There are 3 general groups of mammals
There are 3 general groups of mammals. Include in notes general characteristics for each as well some common examples.

40. Monotremes Lay eggs Transitional species Incubate 12 days
Lick milk from mothers fur

41. MONOTREMES “Egg laying”
Duckbilled Platypus
Anteater
Echidna

42. Marsupials Pouched mammals
Birth to tiny embryo that is not fully developed
Embryo crawls into mother’s pouch to complete development

43. MARSUPIALS Premature babies develop in pouch
Mostly found in Australia/ New Guinea
Kangaroo
Wallaby

44. MARSUPIALS
Only North American Marsupial
Oppossum

45. Placental Mammals Placenta nourishes embryo inside mother
Long gestation period
22 months for elephant
Most successful group of mammals

46. PLACENTAL Embryos nourished inside mother by placenta
95% of all mammals are placental
At least 18 orders

47. Placental Mammals Competitive advantage over monotremes and marsupials
Better nutrition from placenta
Less vulnerable to predators
More advanced at birth

48. Evolution of Placenta from Amniotic Egg (you don’t have to write down)
Reptile
Chorion
Oxygen from air
Amnion
Provides private pond
Yolk Sac
Food for embryo
Allantois
Store urinary waste
Mammal
Chorion
Form placenta to get oxygen & food from mothers blood
Amnion
Provides private pond
Yolk sac
Temporarily make RBCs
Allantois
Form umbilical cord

51. Mammal Classification
14 major orders
Over 4,000 species
About half are rodents
Don’t worry about writing down various order names and groups

52. Order Monotremata
Lays eggs
Young lick milk from mothers fur

53. Order Marsupiallia
Pouch

54. Order Insectivora
Sharp-snout
Small
Burrow underground
Eat insects

55. Order Chiroptera
Flying mammals
Elongated fingers
Echolocation

56. Order Xenarthra
Toothless or peg like teeth

57. Order Carnivora
Large canine teeth
Teeth adapted to shear flesh

58. Order Rodentia
Chisel-like incisor teeth

59. Order Lagomorpha
Four upper incisors
Hind legs adapted for jumping

60. Bats
Only flying mammal
Seed dispersal
Pollination
Control insects

61. Smallest Mammal
Kitti’s hog-nosed Bat
Bumble size
1.5 grams

62. ECHOLOCATION Bats can fly without eyes, but NOT without ears
Bats emit high frequency sound waves that bounce off objects
Can determine size, distance, direction, speed

63. Echolocation

65. Order Cetacea
Front limbs modified into flippers
No hind limbs
Marine

66. Whales Blue whale 100 feet long, 120 tons Loudest animal– 188 dB
9 story building
Loudest animal– 188 dB
Sound travels 100’s of miles

68. Grey Whale

69. Migrates 12,500 miles

70. Grey Whale 50 feet long 35 tons Baleen whale Endangered species
Sift mud
Endangered species

71. Killer Whale

72. Blue Whale Baleen whale Eats krill Heart weighs 1000 pounds
Tiny crustaceans
400 pounds/day
Heart weighs 1000 pounds
Size of a Volkswagen
Endangered species

73. Breaching

74. Killer Whale 12,000 pounds Eat fish, squid, seals and whales
200 pounds/day
Swim 30 mph

75. Humpback Whale

76. Order Pinnipedia
Limbs modified for swimming
Marine carnivores

77. Order Proboscidea
Tusks
Largest living land mammal

78. Order Artiodactyla
Two or four toes

79. Order Perissodactyla
One or three toes

80. Order Primates Opposable thumb Binocular vision
Write down general characteristics of primates below
Opposable thumb
Binocular vision
Well developed cerebrum
Fingers and toes, fingernails usually
Arms rotate around shoulder joint
Mammary glands reduced to one thoracic pair

81. PRIMATES Larger Brain Grasping hand with fingernails instead of claws
2 forward facing eyes
Includes:
Gorillas
Monkeys
Lemurs

82. PRIMATES
Humans are primates too!

83. The End

84. References Content and slides taken from: Seth Garrison the great
Professor Dennis Anderson at Oklahoma City Community College
Kelly Riedell and her zoology website
Prentice Hall Biology 2002
McGraw Hill Zoology 2008