This is a force that acts perpendicularly to the wing.
What is lift?
100
This tends to slow the object down by acting parallel to and in the opposite direction from motion.
What is drag?
100
This represents the distance traveled forward for every distance descended. It typically corresponds directly with the animal's lift-to-drag ratio.
What is glide ratio?
100
This is the ability of wingless animals to experience the joy of flight using "orienting-during-a-fall" behavior.
What is directed aerial descent?
100
This is the number of times gliding evolved in mammals.
What is 6 or more times?
200
This occurs when the leading edge of the wing exceeds a threshold angle that causes a loss of lift and increased drag.
What is stall?
200
Smaller, slower animals feel more of this while flying due to the effects of drag.
What is viscosity?
200
This is a form of gliding that takes advantage of quickly rising air so that a bird can ascend while gliding.
What is soaring?
200
These (2-4) are other species that use directed aerial descent.
What are snakes, frogs, spiders, and other insects?
200
These animals are among the largest modern gliders and are the most aerodynamically sophisticated due to their large wings and maneuverability.
What are colugos?
300
This type of wing reduces drag and produces more lift. To do this, it must have an angle of attack other than zero.
What is a streamlined wing?
300
This is the key measure of wing effectiveness. It's typically higher for longer, narrower wings.
What is the lift-to-drag ratio?
300
These phases (2) allow the animal to accelerate toward the ground and then decelerate as it approaches its target point.
What are the ballistic phase and the aerodynamic phase?
300
This is the (lousy) glide angle that worker ants experience when gliding from tree to tree.
What is 75 degrees?
300
These species is the oldest known glider that supported its wings using struts of dermal bone separate from the ribs.
What is Coelurosauravus elivensis?
400
These variables (4) increase lift.
What are increased wing area, speed, angle of attack, camber?
400
Wingspan divided by the average distance from the front to the back of the wing provides this measurement.
What is aspect ratio?
400
Gliders have this because the body parts that make up their wings, like ribs and legs, function in other ways outside of flying.
What is low aspect ratio?
400
Yanoviak's discovery of directed aerial descent led to these two important implications.
What are survival benefits and sensory and neural mechanisms?
400
This species did not develop longer legs to increase its aspect ratio because it spends more time crawling than gliding.
What are flying squirrels?
500
This is a type of airfoil that produces curvature of the wing surface and unsymmetrical wing shape. These airfoils experience more lift in general and are common to flying vertebrates.
What is camber?
500
This number indicates whether pressure drag or viscous drag is dominant. When high, pressure drag is dominant; when low, viscous drag is dominant.
What is Reynold's number?
500
Quetzalcoatlus would likely have done this due to its large size and wingspan.
What is soar?
500
These (4) are some of the survival benefits conferred by directed aerial descent.
What are ability to return to home tree, reduced risk of injury upon impact, avoiding exposure to terrestrial predators, energy conservation?
500
These structures provide increased wing area and better steering for gliders.