What use is half a wing? A leg evolving into a wing would be a bad leg
long before it was a good wing.
Source:
Brown, Walt, 1995. In the beginning: Compelling evidence for creation
and the Flood. Phoenix, AZ: Center for Scientific Creation, p. 7.
http://www.creationscience.com/
Response:
Half a wing can have any of several uses:
In insects, half a wing is useful for skimming rapidly across the
surface of water (Marden and Kramer 1995; Kramer and Marden 1997;
Thomas et al. 2000).
In larger animals, half a wing is useful for gliding. Airfoils for
gliding appear in several different forms in many different animals,
including
skin between legs on flying squirrels (Petauristinae),
scaly-tailed squirrels (Anomaluridae), flying phalangers, and
flying lemurs
flattened body of the flying snake (Chrysopelea)
large webbed feet on gliding tree frogs (Rhacophorus and
Polypedates)
fins on flying fish (Exocoetidae) and flying squid
(Onychoteuthis)
expanded lateral membranes supported by elongated flexible ribs
on gliding lizards (e.g., Draco)
expanded lateral membranes supported by elongated jointed ribs
on the Kuehneosauridae from the late Triassic
lateral membrane supported by bones separate from the rest of the
skeleton on Coelurosauravus jaekeli, an Upper Permian flying
reptile (Frey et al. 1997)
even an ant (Cephalotes atratus), when it falls, uses its hind
legs to direct its aerial descent back to its home tree's trunk
(Yanoviak et al. 2005).
In immature chickens, wing-flapping enhances hindlimb traction,
allowing the chickens to ascend steeper inclines. This function
could be an intermediate to the original flight of birds. (Dial
2003)
In some flightless birds (e.g., penguins), wings are used for
swimming.
In some flightless birds, wings are probably used for startling
potential predators.
Black herons use their wings to shade the water in which they fish.
Some owls use their wings to hold their prey against the ground.
Nighthawks, woodcocks, riflebirds, and several species of manakins
make noises with their wings as part of sexual displays.
Partial wings may have other useful functions that nobody has
thought of yet.
Dial, K. P. 2003. Wing-assisted incline running and the evolution of
flight. Science 299: 402-404. See also: Pennisi, E., 2003. Uphill
dash may have led to flight. Science 299: 329.
Frey, Eberhard, H-D. Sues, and W. Munk. 1997. Gliding mechanism in the
Late Permian reptile Coelurosauravus. Science 275:
1450-1452.
Kramer, M. G. and J. H. Marden. 1997. Almost airborne. Nature 385:
403-404.
Marden, J. H. and M. G. Kramer. 1995. Locomotor performance of insects
with rudimentary wings. Nature 377: 332-334.
Thomas, M. A., K. A. Walsh, M. R. Wolf, B. A. McPheron and J. H.
Marden. 2000. Molecular phylogenetic analysis of evolutionary trends
in stonefly wing structure and locomotor behavior. Proceedings of the
National Academy of Science USA 97:
13178-13183.
Yanoviak, Stephen P., Robert Dudley, and Michael Kaspari. 2005.
Directed aerial descent in canopy ants. Nature 433: 624-626.
Further Reading:
Brodsky, A. K., 1994. The Evolution of Insect Flight. Oxford
University
Press.