1. Mammal Notes Part III

2. Circulation, Gas Exchange, and Thermoregulation Circulation: Mammals have a 4 chambered heart. http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookcircSYS.html Blood flow: heart– lungs– heart—body– heart

3. http://www.jcu.edu/biology/RESP1.HTM Gas Exchange Inhalation: ribs and diaphragm expand - negative pressure draws air into the lungs.

4. Thermoregulation Maintaining endothermy Heat producing mechanisms: Metabolic heat: heat produced by general cellular metabolism Shivering: heat produced from the muscle contractions that result from shivering.

5. Thermoregulation: Heat Conservation Insulation: of body by fur and or layers of fat Shunting: (limiting) blood flow to extremities or outer tissue. Outer tissue cools while the body core w/ vital organs stays warm.

6. http://www.cartage.org.lb/en/themes/Sciences/Earthscience/Oceanography/OceanLife/MarineMammals/Adaptation/CounterCurrent.jpg Thermoregulation Heat conservation Countercurrent Heat Exchange e.g. Caribou Dolphins Other inhabitants of the cold

7. Thermoregulation Heat conservation Behavior: Mammals use heat conserving postures. Wolves w/ nose tucked in tail http://www.harrison-keller.com/wolves/quiet_moment.jpg http://www.y2012.de/pictures/wolves/sleeping_wolf.jpg

8. Thermoregulation Cooling Radiation: heat lost to environment as blood travels through vessels beneath the skin. (Eg jack rabbit and elephant) Evaporative cooling: via sweat or panting Behavior: many mammals in hot desert climates spend day in burrows or limit activity during the day

9. Thermoregulation (continued) Winter sleep: some mammals will retreat to dens during winter (eg bears, raccoons). Characterized by: Reduced activity Lowered body temp. Reduced metabolic rate Animal is relatively alert, may emerge and become active for periods of time.

10. Photo: March 19, 1972. Minnesota http://www.bear.org/SlideShows/HiddenWorldOfBears/Slide_05.html 7-year-old (black bear) mother with cubs in a den under a fallen tree

11. Thermoregulation Hibernation: A period of winter inactivity Body temp drops to just 2 degrees Celsius. Respiration rate may drop by 98%. Heart Rate may drop by 94%. Rewarming takes several hours.

12. http://www.deepcreektimes.com/kids/chipmunk.jpg http://www2.ncsu.edu/ncsu/univ_relations/news_services/squirrel2.jpg Hibernation Hibernators include: Monotremes Members of Rodentia Members of Insectivora Members of Chiroptera

13. Hibernation in Groundhogs

14. Excretion and Osmoregulation Kidneys Excrete urea Requires water loss (because urea is water soluble)

15. Excretion and Osmoregulation Kidneys Ex. Kangaroo rats: Most efficient mammal kidneys – they lose very little water Do not need to drink water

16. Excretion and Osmoregulation Miller/Harvey, Zoology, 5 th Ed.

18. Excretion and Osmoregulation Miller/Harvey, Zoology, 5 th Ed. Animals with long noses can recapture some water when breathing

19. Mammal Behavior Mammals have complex behaviors that aid in survival. Body language: communication with in own species as well as to other sp. Pheromones: mammals communicate and identify one another through smell. Many mammals live in groups (bison, elk, lions etc..) Some mammals are territorial (e.g. wolves) Some mammals migrate (e.g. caribou)

20. Mammal Behavior Bison in rut Wolves greeting one another (note the position of the black wolf’s head and tail)

21. Bison in Rut

22. Elk in Rut

24. Caribou Migration

25. Tool Use In Chimpanzees