Ornithology Exam 1 Quizzes 3 and 4

Bird Flight and Physiology

• To maximize distance traveled per unit of energy, a bird should fly at a speed that minimizes energy expenditure.
• The supracoracoideus muscle is responsible for lifting the bird's wing on the recovery stroke.
• Intermittent flight, characterized by periods of flapping and gliding, reduces energetic cost associated with fast airspeeds.
• A bird with low aspect ratio wings and low wing loading is likely specialized for maneuverability and lift, such as urban or forest-dwelling birds.

Forces of Flight

• A bird must overcome forces of lift, drag, and weight to fly.

Respiratory System

• Gas exchange does not occur in the air sacs of a bird's respiratory system.
• Endothermy, the ability to regulate body temperature, is true for birds, and it allows for:
  • Increased metabolic efficiency
  • Improved muscle function
  • Enhanced flexibility in activity patterns
• A bird's metabolic rate increases at ambient temperatures below the lower critical threshold and above the upper critical threshold due to the need to maintain a stable body temperature.
• The bird respiratory system is more efficient than the mammalian system because it uses air sacs, which provide a larger surface area for gas exchange, and the lungs are more efficient at extracting oxygen.

Torpor and Size

• Torpor, a state of reduced metabolic activity, is not a practical strategy for large birds because it would lead to a significant loss of body heat, making it difficult to recover.

Quizzes 3 and 4 leading up to exam 1. MIZ 2024