In some cases, the animal who serves as the receiver of the warning signal reacts by means of an innate system that exists independently of experience. Generally, however, a predator must learn the significance of the warning signal through experience. If the predator is a slow learner, or if the warning signal is not sufficiently distinct to avoid confusion with beneficial sensory impressions that the predator receives, several experiences may be necessary. Natural selection, therefore, will favour warning systems that are devoid of ambiguity. Experimentation has shown that certain birds and mammals, at least, are capable of acquiring and retaining knowledge of some aposematic mechanisms from a single experience.
An-active-trap-of-the-sundew-Sensitive-tentacles-topped-withAn active trap of the sundew (Drosera capensis). Sensitive tentacles topped with red …[Credits : © Thomas C. Boyden]
Passive-traps-of-the-slender-pitcher-plant-The-leaf-bladePassive traps of the slender pitcher plant (Nepenthes gracilis). The leaf blade narrows into …[Credits : © Robert and Linda Mitchell]
The-labellum-of-the-mirror-ophrys-The-colouring-so-closelyThe labellum of the mirror ophrys (Ophrys speculum). The colouring so closely resembles that …[Credits : E.S. Ross]
An anglerfish (order Lophiiformes) luring and capturing prey.[Credits : Encyclopædia Britannica, Inc.]
Some fishes have adapted unusual structures and behaviours to catch prey and to avoid becoming prey.[Credits : Encyclopædia Britannica, Inc.]
Leaf katydids (subfamily Pseudophyllinae) precisely mimic the form of leaves. The green leaf …[Credits : Encyclopædia Britannica, Inc.]
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