Chickens bob their heads while walking. So do cranes, magpies
and quails. In fact, head bobbing is a unique feature in birds
and occurs in at least 8 of the 27 families of birds.
There are a few theories why some birds bob their heads when they
walk:
1. Assists with balance
2. Provides depth perception
3. Sharpens their vision
However, most studies suggest that birds in motion bob their heads
to stabilize their visual surroundings. In comparison, we rely
more on our eye movements, not our head movements, to catch and
hold images while in motion.
Picture a pigeon on a moving treadmill. What do you think would
happen as the pigeon walks with the speed of the treadmill and
its environment remains relatively the same? Dr. Barrie J Frost
(1978) did this experiment and the pigeon’s head did not
bob.
Dr. Mark Friedman (1975) also conducted a series of experiments
to test the head bobbing actions of birds, using doves. His research
demonstrated that the head movement is controlled more by visual
stimulation than movement of the body.
Scientists continue to research head bobbing in birds. For example,
scientists are currently investigating question such as “Why
do some birds exhibit head bobbing, while other do not?” For
more information on this topic see the related Web sites section.
Related
Web Sites |
- Animal
Diversity: Family Columbidae (pigeons and doves) -
Animal Diversity Web is an online database of animal
natural history, distribution, classification, and
conservation biology at the University of Michigan.” Information
about the pigeon and dove family is presented.
- Avian
Visual Cognition - A cyberbook edited by Robert
C. Cook about visual cognition in birds.
- PigeonWatch:
An International Study of Feral Pigeon Colors - "PigeonWatch
participants observe pigeons and send their data to
the Cornell Lab of Ornithology …” Instructions
and data forms, videos, pigeon color morphs, pigeon
courtship behavior, and cool pigeon facts are some
of the information presented on this Web site.
- Biomotion
Lab: The Functional Significance of Head-Bobbing in
Birds - The Biomotion Lab, directed by Dr. Nikolaus
Troje and in collaboration with Dr. Barrie Frost, researches
visual perception and cognition. A brief summary on
head bobbing in birds is presented.
- Visual
and Auditory Neuroscience Laboratory - Dr. Barrie
Frost directs this laboratory, which studies “brain
mechanisms for processing visual and auditory information” in
animals. You can find information about his research
and a bibliography of his publications through the
Lab’s Web site.
|
Further
Reading |
- Friedman,
Mark. Visual control of head movements during avian locomotion. Nature,
v. 255, May 1, 1975: 67-69.
- Frost,
B. J. The optokinetic basis of head-bobbing in the pigeon.
Journal of experimental biology, v. 74, June 1, 1978:
187-195.
http://jeb.biologists.org/cgi/reprint/74/1/187
- Jackson,
John. Pigeons. Danbury, CT, Grolier, c2004.
48 p. (Juvenile literature)
- Physiology
and behaviour of the pigeon. Edited by Michael
Abs. London, New York, Academic Press, c1983. 360 p.
- Rodieck,
R.W. The first steps in seeing. Sunderland,
MA, Sinauer Associates, c1998. 562 p. .
- Troje,
Nikolaus F. and Barrie F. Frost. Head-bobbing in pigeons:
how stable is the hold phase? Journal of experimental
biology, v. 203, March 1, 2000: 935-940.
http://jeb.biologists.org/cgi/reprint/203/5/935
- Vision,
brain, and behavior in birds. Edited by H. Philip
Zeigler and Hans-Joachim Bischof. Cambridge, MA, MIT
Press, c1993. 415 p.
|
For
more print resources...
Search on "birds
-- behavior," "birds -- physiology," "columbidae," "pigeons," or "visual
pathways"
in the Library of Congress Online
Catalog. |
Domestic pigeon. Photo:
The Washington Department of Fish and Wildlife.
Bavarian
pigeon fleet with tiny cameras. From the online Remote
Sensing Tutorial (NASA)
"The Pigeon of Passage." From the Special Collections
of the National Agricultural Library
Extinct
passenger pigeon. Photo: National Conservation Training Center.
The
sun can effect the navigational abilities of homing pigeons
during geomagnetic storms. From the National Aeronautics and
Space Museum (NASA)
This
woman has been feeding the pigeons in Lafayette Park, D.C., almost
daily
for
thirteen
years. Prints & Photographs
Division, Library of Congress.
Vincent Price
and three women holding and feeding pigeons, Italy. Prints & Photographs
Division, Library of Congress.
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