1. http://www.youtube.com/watch?v=b1dekS aGhlc&feature=relatedhttp://www.youtube.com/watch?v=b1dekS aGhlc&feature=related http://www.youtube.com/watch?v=VFUNh TdcNdk&feature=relmfuhttp://www.youtube.com/watch?v=VFUNh TdcNdk&feature=relmfu http://www.youtube.com/watch?v=Jq9TCb _xQ_A&feature=relmfuhttp://www.youtube.com/watch?v=Jq9TCb _xQ_A&feature=relmfu

2. Dial et al. 2008

3. WAIR Hypothesis as transition to flight Pros: Developmental stages/behaviors of modern birds may resemble ancient stages/behavioral transitions Pros: Theoretically possible that proto wings had a use, and could have led to flight in ground-based species. –Same arm stroke that keeps baby bird or plucked wing bird on incline also contributes to controlled falls –As longer, more aerodynamic feathers evolved, flight becomes feasible with these small arms and same arm stroke. Cons: Could WAIR just be an exaptation of existing adaptations for flight? Cons: others? How when did airfoil shape evolve? Perhaps a “trees-down” gliding hypothesis is better here? Are the “ground-up” and “trees-down” hypotheses mutually exclusive?

4. Bird Physiology Overview of Metabolism (Digestion and Excretion in lab) Feathers and flight are conspicuous features of birds As important but less conspicuous: metabolic adaptations

5. Endothermy ‘maintenance of a high body temperature through the production of metabolic heat’ ~40 °C On avg. 5* C higher body temperature than mammals! Advantages of high body temp: –Quick Reaction Time (doubles with 10* C increase) –Increased Muscular speed and power (triples every 10* C) –Increased muscular endurance (e.g. hours or days of flying) –Increased range of habitat Use Altitudes Climates Flying Exothermy

6. Cardiovascular System Increased metabolic demands require increased cardiovascular demands The cardiovascular system delivers oxygen to body cells (and removes metabolic waste) Also plays a key role in maintaining a bird's body temperature

7. Birds, like mammals, have a 4-chambered heart (2 atria & 2 ventricles), with complete separation of oxygenated and de-oxygenated blood lungs body

8. Avian heart Birds tend to have larger hearts than mammals (relative to body size and mass) House Sparrow's: heart 1.68% of the body weight and average pulse 460 bpm Ruby-throated Hummingbird: heart 2.37% of body weight and a pulse rate of 615 bpm Humans heart: 0.42% of body weight and pulse rate at rest averages 72 bpm

9. Blood http://www.youtube.com/watch?v=yd_w 3biT3TU Bar-headed geese, flight altitude = 9000 m Emperor Penguin—500m deep, 20 min.

10. Avian blood Plasma: –water (~85%) –protein (~9-11%); –glucose (blood glucose levels in birds are greater than in mammals) –amino acids, waste products, hormones, antibodies, & electrolytes red blood cells are elliptical and nucleated red blood cells are about 6 x 12 microns in size (mammalian RBC's 5.5 - 7.5 microns) Avian red blood cells have a lifespan of 28- 45 days (shorter than mammals, e.g., about 120 days in humans)

11. Myoglobin = high affinity for oxygen Vasoconstriction in non-essential systems

12. 9 Avian Air Sacs - Compared to mammals, birds have relatively small lungs ( + air sacs that play an important role in respiration)

13. What causes the air to move from area to area? Sternum moves forward and downward while vertebral ribs move cranially Expands thoracoabdominal cavity and expands air sacs Air pressure decreases in air sacs causing air to move in INHALATION

14. EXHALATION Sternum moves backward and upward while vertebral ribs move caudally Volume of thoracoabdominal cavity is reduced Air pressure increases in air sacs causing air to be pushed out What is this? No penalty to hyperventilation!

15. Increased basal metabolic rate also means heat stress Expose Wing Bend Panting Ruffle Crown Feathers Ruffle Back Feathers Expose Legs Wet Abdomen How does feather color affect heat loss/absorption?

16. Evaporative Cooling with Gular Fluttering

17. Specialized muscles control feather movement for insulation and exposure How birds deal with cold stress

18. Dermal Shunts Reduce Heat Loss in Feet Posture - at low temperatures, birds can withdraw feet into plumage to reduce heat loss tuck head & neck under wing to reduce heat loss Also reduces distance traveled for blood

19. Remember…Hummingbirds have the highest energy use / body mass of all birds (1600 Kcal/Kg/Day), 1200 heart beats per minute Dealing with Cold Stress: Torpor and hypothermia Chickadees can become hypothermic (body temp -6* C) Hummingbirds can go into full torpor (body temp -20* C)

20. Rico-Guevara and Rubega http://www.pnas.org/content/suppl/2011/04/28/1 016944108.DCSupplemental/SM01.movhttp://www.pnas.org/content/suppl/2011/04/28/1 016944108.DCSupplemental/SM01.mov http://www.pnas.org/content/suppl/2011/04/28/1 016944108.DCSupplemental/SM02.movhttp://www.pnas.org/content/suppl/2011/04/28/1 016944108.DCSupplemental/SM02.mov http://www.pnas.org/content/suppl/2011/04/28/1 016944108.DCSupplemental/SM03.movhttp://www.pnas.org/content/suppl/2011/04/28/1 016944108.DCSupplemental/SM03.mov http://www.pnas.org/content/suppl/2011/04/28/1 016944108.DCSupplemental/SM04.movhttp://www.pnas.org/content/suppl/2011/04/28/1 016944108.DCSupplemental/SM04.mov

21. What journal was this in? What techniques were used? Where? What species were used? Likes/Dislikes? Implications for the evolution of nectar feeding?

22. Upcoming Lab at Union Bay tomorrow, 8 AM, split class Monday—Mike Beecher Tues—Union Bay field lab weather permitting Wed—Sievert Rohwer

23. Emperor Penguins Huddle Together http://www.youtube.com/watch?v=q92situvqXM