Class Mammalia

1. Class Mammalia

2. Characteristics Mammary glands Hair Diaphragm Three middle ear ossicles

3. Characteristics Heterodont dentition Sweat, sebaceous, scent glands Four chambered heart Large cerebral cortext

4. Mammary Glands

5. Hair Regulate body temperature Protection

6. Ossicles

7. Dentition

8. Heterodont Dentition

9. Human teeth

10. Large Cerebral Cortex

11. Types of Mammals Monotremes Marsupials Placental

12. Monotremes Duck-billed Platypus Echidna (Spiny Anteater)

13. Marsupials Pouched mammals Not well develop young

14. Placental Mammals Gives birth to young that remain inside the mother’s body until their body system are able to function independently.

15. Gestation Period The time the young spend inside the mother’s uterus.

16. Animal Gestation Period (days) Animal Gestation Period (days) Camel 406 Hyena 110 Cat 62 Kangaroo 40 Cow 280 Lion 108 Chimpanzee 237 Mink 50 Dog 62 Monkey, rhesus 164 Dolphin 276 Mouse 21 Elephant, African 640 Opposum 13 Ferret 42 Orangutan 245-275 Fox 52 Pig 113 Giraffe 395-425 Rabbit 32 Goat 151 Rat 21 Guinea pig 68 Reindeer 215-245 Hamster 16 Seal, northern fur 350 Hedgehog 35-40 Sheep 148 Horse 337 Skunk 62 Human 266 Squirrel, grey 44

17. Decrease of Metabolic Rates Torpor -time of decreased metabolism and lowered body temperature that occurs daily in bats, humming birds and some other small birds and mammals. Hibernation -decrease metabolism and lowered body temperature that may last for weeks or months. Winter Sleep-occurs in some large mammals. Sustain mammals through periods of winter inactivity no dropping of temp. substancially . Aestivation -period of inactivity in some animals that must withstand extended periods of drying. Common in invertebrates, reptiles, and amphibians.