1. Soaring Flight

3. Andean Condor soaring http://www.youtube.com/watch?v=4j6qDJWiwbA

4. Flapping Flight downstroke: the wing beats down and forwards, producing lift and propulsion. upstroke: the wing flexes in towards the body (largely due to a rotation of the humerus about its long axis) and then rises and extends ready for the next downstroke. Passive aerodynamic lift provides the restoring force for the upstroke under most cruising conditions, although during takeoff the upstroke is powered.

5. Wing Stroke

6. Take-off, short flight and landing

7. There are two main flight muscles attaching to each wing. The pectoralis muscle powers the downstroke and is proportionately very large in birds (up to 35% of body weight). The supracoracoideus is much smaller and has a tendon which curves around to attach to the top of the humerus.

8. Diagram showing the large fan-shaped pectoralis muscle converging to an attachment on the humerus, and the smaller supracoracoideus deep to it at the front, attaching to the top of the humerus via a tendon passing through the foramen triosseum.

9. The supracoracoideus can provide power to the upstroke if required but more usually produces a rapid rotation of the humerus at the top of the upstroke. In addition there are 48 other muscles within the wing and around the shoulder which produce the wide range of movements of the wing and its feathers.

10. Long, narrow wings: high speed gliding in high wind - Albatross Short, rounded wings: fast takeoffs and rapid maneuvers - Grouse Slim, unslotted wings permit fast, efficient flight in open habitat - Falcon Slots in wings of intermediate dimensions increase lift and gliding ability – Buteo hawks

11. Assuming birds of same weight: Wing Loading: weight / wing area Aspect Ratio: wing length / wing breadth

12. Hummingbird Flight

13. Hummingbird Videos http://www7.nationalgeographic.com/ngm/0701/feature4/multimedia.html Especially Note Purple-crowned Woodnymph and Marvelous Spatuletail

14. Kestrel Flight – hovering http://www.youtube.com/watch?v=31Xw75hAwIc

15. Wing beats vary by type of bird as well as the speed and weight. Robert Burton in the book Bird Flight estimates this range: Gray heron2 wing beats per second Herring gull2.8 wing beats per second Starling5.1 wing beats per second Pheasant9 wing beats per second Mockingbird14 wing beats per second Tits25 - 27 wing beats per second Ruby-throated hummingbird80 wing beats per second

16. Carolina Wren