Mammals

1. Mammals

2. Class Mammalia • Includes 4000 species • Most dominant land animals on earth. • Two identifying characteristics: • Hair/fur • Mammary glands which produce milk

3. Origin Fossil skeletons show that early mammals had large eye sockets, which may have meant that they were active at night. Mammals did not compete with dinosaurs for food, for the would feed on insects.

4. Origin Mammals were not abundant during the Mesozoic era. Fossils of the first mammals are scarce thus indicating that they were not as abundant. The Cenozoic era is named the age of mammals, for this is the time which mammals rapidly started to increase

5. Evolution •Animals evolved from the group of reptiles called Therapids. •Therapids have both reptilian and mammalian characteristics. •Therapids have a jaw bone composed of 5 bones rather than a simple jaw bone. .

6. Evolution •Like mammals, Therapids have specialized teeth adapted for specialized functions. •The earliest mammalian fossil found is from the early Mesozoic era, 200 million years ago

7. Characteristics of Mammals • Endothermic • Well-developed brains

8. Characteristics of Mammals • Heart has 4 chambers • Diaphragm (muscle) aids in breathing

9. Characteristics • Mammals have single lower jaw • Most species have 4 different types of teeth: Incisors, canines, cuspids, and bicuspids • Various types of teeth for different diets

10. Characteristics • Mostly viviparous (live birth) • Females secrete milk from mammary glands to feed newborn young.

11. Distinguishing Features Two features distinguish them from other invertebrates: hair and production of milk.

12. Class Mammalia • Subclass Prototheria- extinct mammals with unique skull structure • Subclass Theria- Living mammals distinguished by skull • Infraclass Ornithodelphia- Monotremes • Infraclass Metatheria- Marsupials • Infraclass Eutheria- Placentals

13. Order Monotremata • Oviparous or egg laying mammals • Only 3 in existence • Duck-billed platypus and two species of spiny anteaters called echidna. • Not completely endothermic (their body temperature is lower and fluctuates more than other mammals) • Mammae without nipples • Edentulous as adults • Limbs modified for swimming or digging • Australia and New Guinea

14. Duck-Billed PlatypusOrnithorhynchus anatinus • Only member of the mammal family Ornithorhynchidae • Greek platys meaning broad and pous meaning foot • Several reptilian characteristics: same opening for reproduction and eliminating waste products, the ability to lay eggs • The world's only venomous furred animal • Spur on hind foot • Females loose after one year • Bill contains an electro-receptor system

15. Echidna (Spiny Anteater)Tachyglossus aculeatus • "Echidna" derives from the Latin word for "viper” • Tongue protrudes like a snake • Nocturnal • Terrestrial and burrowing • Females normally lay only one egg

16. Monotremata Duck-billed platypus Spiny anteater

17. Infraclass Metatheria(Marsupials) • Old classification placed all marsupials in a single order • More recent classifications have recognized the diversity and radiation of Marsupials • Marsupials now separated into seven orders • Range, North America, Central America, South America, Australia, New Guinea, adjacent islands

18. Subclass TheriaInfraclass Metatheria (Marsupialia) Order Didelphimorphia OpossumsOrder Paucituberculata Rat OpossumsOrder Microbiotheria Monito del monteOrder Dasyuromorphia Thylacines, numbats, dasyuresOrder Peramelemorphia BandicootsOrder Notoryctemorphia Marsupial moleOrder Diprotodontia Koalas, wombats, kangaroos, etc

19. 250 species of marsupial species exist in Australia, New Guinea, Tasmania, And the Americas • . Tasmanian Devil

20. Marsupials • Give birth to tiny immature young that crawl to a pouch on the mothers belly immediately after they are born. • Marsupium- Fold of skin protecting nipples

21. They attach themselves to milk secreting nipples nursing until they are mature enough to survive outside the pouch.

22. Syndactyly

23. American Marsupial Order Didelphimorphia- Opossum

24. Order Paucituberculata • Rat Opossums

25. Order Microbiotheria- Monito del Monte

26. Order Dasyuromorphia • Thylacine • Numbat Dasyure

27. Order Peramelemorphia- Bandicoots

28. Order Notoryctemorphia- Marsupial Moles

29. Order Diprotodontia Wombats Kangaroos

30. Placental Mammals

31. Characteristics of Placentals • 95% of all mammals • Carry unborn young in the uterus until young can survive in the wild. • Oxygen and nutrients are transferred from mother’s blood to baby’s blood

32. Placental Characteristics • The placenta is a membrane providing nutrients and waste & gas exchange between the mother and developing young • Gestation period-is the time which mammals develop in mother’s uterus

33. Mammals are a diverse group living on land and in water. Some mammals can fly! Malaysian Fruit Bat

34. Order Insectivora • Consists of 400 species • Includes shrews and moles Shrew Mole

35. Order Insectivora • Small animals with high metabolic rate and found in North America, Europe, and Asia. • Most have long pointed noses that enable them to grub for insects, worms, and invertebrates. • Live on ground, trees, in water, and underground.

36. Order Rodentia • Largest mammalian order having over 2,400 species. • On every continent except for Antarctica • Includes squirrels, marmots, chipmunks, gophers, muskrats, mice, rats, and porcupines. Chipmunk

37. Marmot Porcupine Squirrel

38. Only two incisors in each jaw, grow as long as rodent lives, and used for gnawing

39. Order Lagomorpha • Includes rabbits, hares, and small mountain mammals called pikas. • Found worldwide • Warrens- families of rabbits Hare Pika

40. Rabbits vs. Hares • Rabbits are smaller and slower • Shorter ears and hind legs with smaller feet • Solid colored fur • A young rabbit is a bunny • Altricial • Hares are generally larger and faster • Hares have longer ears, longer hind legs, and larger feet • Hares have black markings on their fur • A young hare is called a leveret • Precocial

41. Order Lagomorpha Double row of incisors, large front teeth backed with two smaller ones, adaptation for herbivorous diet.

42. Order Edentata/Xenarthra • Made up of 30 living species including anteaters, armadillos, and sloths. • The name edentate means “without teeth” • Those with teeth have single root with teeth and no enamel

43. Anteater Sloths

44. Edentates have adaptations for insectivorous diets, including a long, sticky tongue and clawed front paws Anteater feeding at a Termite mound

45. Sloths, on the other hand have continuously growing teeth as an adaptation for grinding plants

46. Chiroptera • Made up of over 900 species of bats • Live throughout the world except in polar environments

47. A bat’s wing is modified front limb which skin membrane between extremely long finger bones • Bats use thumbs for climbing, walking, or grasping

48. Order Chiroptera • Most bats are active at night and have a special way to navigate using echolocation (bouncing off high-frequency sound waves) • Frequency of returning sound waves with the size, distance, and rate of movement of different objects

49. Order Chiroptera • Bats that use echolocation have small eyes and large ears. • Feed on insects and have teeth specialized for such diets

50. Some feed on fruit and flower nectar and do not use echolocation. • These bats are sometimes called flying foxes, have large eyes and keen sense of smell.