Eating Habits of Reptiles (Part 7)© Janat Khatoon
Mar 24, 2001
The chameleon is as fully committed to living in trees as any reptile in the world and its tongue is a trap for small tree-dwelling creatures. The tongue trap would not work very well on the ground. There are generally too many obstructions close to the ground for such long-range shooting; moreover, the tongue sags at the end of the trajectory and its sticky surface would pick up dirt. In any case, chameleons are arboreal and their whole structure is adjusted to living in trees. Their twig-grasping feet look like the jaws of pliers. Their eyes roll about freely; wholly independent of one-another, hidden in the depths of windowed turrets that shield their glint would generally come too late.
The famous chameleon color-changes range through a variety of hues and shifts of pattern. Most chameleons are able to assume colors and patterns that blend into their surroundings. The dwarf chameleons of the genus Brookesia have more or less fixed patterns and a body form that in silhouette suggests a leaf.
Adaptations are neither acquired nor used in a vacuum. From the start, and increasingly as they are perfected, new structures and functions are bound to affect and be affected by whole organization of the animal. A modification occurs, and there follows a whole organization of the animal. A modification occurs, and there follows a whole system of other changes to compensate for it or to exploit it. The idea is beautifully shown in some of the ramifications of venom production in reptiles, which is clearly related to the basic snake specialty of going after over-sized food too active to be merely seized and swallowed.
Of all the feeding adaptations of reptiles, the ability of certain snakes and of the lizards, the Gila monster and its close relative the Mexican beaded lizard, to kill prey by the injection of poison seems the most dramatic. The poison of snakes fascinated men long before Cleopatra clutched the famous asp to her bosom, and it has probably inspired as much myth and folklore as any adaptation in the animal kingdom. Humans, of course, experience it primary as a defensive weapon used by the snakes, since man is not a part of any poisonous reptile’s food plan; but man has a way of making these things his own, forgetting the main and original purpose which such adaptations serve-in this case, the procuring of food. Thus the lore and legend of snake venom usually revolves around human experience, and the rabbit or rat or other small mammal that is the normal victim of a poison snake dies and is eaten in obscurity.
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