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PAGE 1 CONTENTS HEARING SIGHTPage 2 contents SMELL TOUCH COMMUNICATION WEIGHTLIFTING Chameleons prefer to LICK the dew off of leaves over drinking still water. They have been known to lick the branches, or to be more accurate, taste test the branch with their tongue to determine if the territory is occupied. A male chameleon will rub its cloaca (vent) on branches after defecating, it is thought to mark their territory. This "taste test" or smelling of the branch is a substitution for their inability to smell. Their Jacobson's organ, located in the mouth of most reptiles, (used to "smell" particles picked up by the tongue) is virtually non-functioning, however, taste buds have been found in their tongues. Very little research has been done on this because it is considered to be an unimportant issue. I think there must be something important about taste to the chameleons. They tend to reject the same foods after a while, and seem to get excited about others. See Myths -Tongue
literature cited (2,
Chameleons have very limited hearing, tuning in to frequencies between 200 and 600 Hz as compared to most other lizards from 100 to 4000 Hz, and to humans 20 to 20,000 Hz. Most snakes can pick up sound waves between 100 to 700 Hz. Chameleons ears have degenerated over time, are covered with scales, and possess no eardrums. Female C. Oweni, and C. Johnstoni are known to produce low purring sounds when being handled by humans or approached by males of their species. Male veiled chameleons have been recorded (see LINKS PAGE - interesting sites to hear this) "hooting" during the pre-mating rituals.
literature cited (2, Chameleons have one of the most sophisticated eyes in the animal kingdom. They are described as binocular (each eye moves independently of the other) and are probably the chameleon's greatest sense. Combined they provide nearly 360 degree vision without turning the head, and allow the chameleon to see in front of and behind him When searching for prey, the eyes are constantly moving in independent directions. when the meal is spotted BOTH eyes lock on the target and the tongue ZAPS it (see TONGUE on MYTHS PAGE). When the tongue is released, the eyes are closed for protection from projectile damage. More protection for these irreplaceable assets is exercised when the animal sleeps. Their eyelids close, and the eye rolls down until the pupil is behind a protective bone. Still even more insurance against damage comes in the form of scale covered eye lids. They completely cover the entire eye except for a small opening for the pupil. The first time a chameleon is observed cleaning its eye can cause great stress to the chameleon owner. It appears that their eye is about to pop out of the socket. They will "blow up" their eye turret and rub it on something to clean it or to knock off loose skin during shedding. NEGATIVELY POWERED LENS IN THE CHAMELEON'S EYES According to a paper published in the 23 February 1995 issue of Nature, research done by Matthias Ott and Frank Schaeffel of the University Eye Hospital, Department of Experimental Ophthalmology in Tubingen, Germany has shown that chameleon's eyes have a negatively powered lens. This negatively powered lens gives the chameleon a fast-focus telephoto eye that can judge distance much like a reflex camera, unlike other vertebrates whose eyes must triangulate on an object using binocular vision to get a distance bearing. In the paper, Ott and Schaeffel also show that the image that forms on the retina of the chameleon is 15% larger than it would be for other vertebrates. The following is the introduction of the published paper.
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