Coral snakes hold a special place in snake biology studies
Coral snakes hold a special place in snake biology studies because a number of non venomous or mildly venomous colubrid snakes as well as at least one caterpillar species, mimic the bright, striking coral snake colour scheme - alternating bands of red, yellow (or white), and black. In Costa Rica alone, at least 10 types (genera) of colubrid snakes imitate - to varying degrees - the colour patterns
of coral snakes (see Plate 14 for examples).
The function of the mimicry apparently is to take advantage of the quite proper respect many predatory animals show toward the lethal coral snakes. Ever since this idea was first proposed more than a hundred years ago, the main argument against it has been that it implied either that the predators had to be first bitten by a coral snake to learn of their toxicity and then survive to generalize the experience to all snakes that look like coral snakes, or that the predators were born with an innate fear of the coral snake colour pattern.
It has now been demonstrated experimentally that several birdpredators on snakes (motmots, kiskadees, herons, and egrets) need not learn that a coral snake is dangerous by being bitten - they avoid these snakes instinctively from birth. Thus, many snakes have evolved as defensive mechanisms colour schemes that mimic that of coral snakes. (However, some biologists argue that this explanation falls apart because, they say, the alternating colour bands of the coral snake's body function as camouflage and not to warn predators away, and also because the snakes' mammalian predators lack colour-vision and therefore could not make use of the patterns to avoid the mimics.)
Non venomous snakes also mimic some of the behaviour of poisonous snakes, the most obvious example being that a good many snakes, when threatened, coil up and wiggle the tips of their tails, as do rattlesnakes and some other vipers.
If you want to read about Eco-Tourism, Ecology, Behavior, Breeding and more of Costa Ricas' Fauna, we recommend to buy the Travelers' Wildlife Guide of Costa Rica by Les Beletzky (or Belesky) with beautiful illustrations by Davis Dennis. This priceless guide is our constant companion, when we travel around Costa Rica, Panama and Nicaragua.
To buy the complete book visit Interlink Books
The team of FlamingoLink, S.A. wishes you the best of times in our little paradise called Costa Rica.
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