2. Hair and Mammary Glands
Chapter 30
Mammals
30.1 Mammalian Characteristics
Hair and Mammary Glands
Two characteristics that distinguish members of class Mammalia from other vertebrate animals are hair and mammary glands.
Mammary glands: produce and secrete milk for young

3. Sensory devices (whiskers)
Chapter 30
Mammals
30.1 Mammalian Characteristics
Functions of Hair
Insulation
Camouflage
Sensory devices (whiskers)
Waterproofing
Signaling (tail color)
Defense (quills)

4. Other Characteristics
Chapter 30
Mammals
30.1 Mammalian Characteristics
Other Characteristics
Endothermic
Source of body heat is internal.
Heat is produced by a high metabolic rate.

5. 30.1 Mammalian Characteristics
Chapter 30
Mammals
30.1 Mammalian Characteristics

6. Mammals are divided into 4 trophic categories depending on diet:
1. Insectivores: feed on insects
2. Herbivores: feed on vegetation

7. 3. Carnivores: feed on herbivores
4. Omnivores: feed on plants and animals

8. Carnivores use canines to stab and premolars to slice and shear meat
Chapter 30
Mammals
30.1 Mammalian Characteristics
Teeth
Carnivores use canines to stab and premolars to slice and shear meat

9. Incisors of insectivores are long and curved, functioning as pincers

10. Teeth location

11. Excretory System

12. Excretion Liver transforms nitrogenous waste into urea
Chapter 30
Mammals
30.1 Mammalian Characteristics
Excretion
Liver transforms nitrogenous waste into urea
Kidneys filter urea from blood and combine it with other waste to form urine

13. Kidneys excrete or retain the proper amount of water in body fluids
Enables mammals to live in extreme environments

14. Respiratory System

15. Mammals are the only animals that have a diaphragm.
Chapter 30
Mammals
30.1 Mammalian Characteristics
Respiration
Well developed lungs
High levels of oxygen are required to maintain a high level of metabolism.
Mammals are the only animals that have a diaphragm.

16. Diaphragm: sheet of muscle found below the lungs that allows the chest cavity to enlarge

17. Circulatory System

18. Double looped, closed circulatory system
4 chambered heart
Double looped, closed circulatory system
One loop: blood travels between heart and lungs
Second loop: blood travels from heart to the rest of the body

19. 30.1 Mammalian Characteristics
Chapter 30
Mammals
30.1 Mammalian Characteristics
Circulation
Keeping oxygenated and deoxygenated blood separate makes the delivery of nutrients and oxygen more efficient.

20. Nervous System

21. 30.1 Mammalian Characteristics
Chapter 30
Mammals
30.1 Mammalian Characteristics
The Brain and Senses
Highly developed brains.
Cerebral cortex is responsible for coordinating conscious activities, memory, and the ability to learn.
Cerebellum is responsible for balance and coordinating movement.

22. Most mammals see in black and white
Strong sense of smell, taste, and hearing

23. Chapter 30
Mammals
30.1 Mammalian Characteristics
Glands
Glands: secretes a variety of fluids that helps to regulate a mammal’s internal environment.
Ex. Sweat glands

24. Movement
Mammals must find food, shelter, and escape from predators.

25. In mammals, the egg is fertilized internally.
Chapter 30
Mammals
30.1 Mammalian Characteristics
Reproduction
In mammals, the egg is fertilized internally.
Development of the embryo takes place in the female uterus.

26. Mammal Classification (based on reproduction)
Chapter 30
Mammals
30.2 Diversity of Mammals
Mammal Classification (based on reproduction)
Monotremes
Marsupials
Placental mammals

27. Reproduce by laying leathery eggs
Chapter 30
Mammals
30.2 Diversity of Mammals
Monotremes
Similar to reptiles
Reproduce by laying leathery eggs
Have a cloaca
Echidna

28. Examples of Monotremes
Echidna
Duck billed platypus

29. Live birth but very early stage
Chapter 30
Mammals
30.2 Diversity of Mammals
Marsupials
Live birth but very early stage
Crawl into a pouch made of skin and hair and continue development
Ex. Kangaroo, opossum, koala
Kangaroo

30. Chapter 30
Mammals
30.2 Diversity of Mammals
Placental Mammals
Give birth to live young that do not need further development within a pouch
Shrew
Humpback whale

31. Placenta: structure that provides oxygen and nutrition, removes waste