Читать книгу The Circle of Knowledge: A Classified, Simplified, Visualized Book of Answers - Various - Страница 284

In the American rattlesnakes, at each periodical casting of the skin or slough, a little knob remains at the end of the tail. A series of these loosely united together make up the “rattle,” used for the production of warning sounds. The “hissing” of a snake has the same purpose. Venomous snakes also commonly assume a warning attitude, raising the front part of the body from the ground and, in some cases, as illustrated by the cobra, inflating a kind of hood—in this particular instance bringing a black, spectacle-shaped mark into prominence.

But in these and other animals it must not be supposed that the “warning” is for the benefit of the prey, but may be taken as a hint to aggressive birds and mammals that discretion is the better part of valor. The success of this device is shown by the terror with which all monkeys regard serpents.