nature A Mangrove Pit-Viper, one of the world's deadliest snakes, deciding whether to attack
They’re Coming to Get You… WE HAVE LOOKED AT POISONOUS PLANTS A NUMBER OF TIMES IN OUR ARTICLES. LET’S LOOK AGAIN AT SOME OF THE POISONOUS ANIMALS THAT ARE OUT THERE … WAITING …!
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n fact, there aren’t really that many of them, especially in this lovely part of France. Even worldwide, the list is fairly brief. First, though, we must decide exactly what we mean by “poisonous”. Venomous or Poisonous? Some animals use their toxic products to enable them to catch prey more effectively. In these cases, the toxins must be introduced into the prey’s body, so a form of injection is required. This can be active injection, by means of a hollow or grooved tooth that delivers the toxin into the prey’s body directly, or passive perfusion, in which the toxin mixes with the predator’s saliva and enters a wound produced by the otherwise quite normal teeth of the predator. Animals that do this are venomous. Others use their poison defensively, either secreting it onto their
bodies or storing it in certain of their body-tissues, so that if they are threatened by a potential predator, the unpleasant or harmful effect of the toxin will deter the predator and perhaps save the prey animal’s life. Such animals are poisonous. The extreme examples of this are the Poison Dart (or ‘Arrow’) frogs of South America, whose toxin, exuded onto the skin of the frog in time of danger, can kill a human, though this is not the frog’s intention. Indeed, killing the attacker is counter-productive; a poisonous animal wants the attacker to live, so it learns not to attack again, and may even pass this knowledge on to its fellows. This is complicated by the fact that venomous creatures sometimes reserve their envenomating skills for self-defence and will, if provoked, attack if they
By Mik
e Geo r ge
Mike George is our regular contributor on wildlife and the countryside in France. He is a geologist and naturalist, living in the Jurassic area of the Charente
perceive a threat. Honey-bees, wasps etc. come into this category. Sometimes the envenomating system is dual-purpose. The most spectacular examples of this are the Spitting Cobras, which have hollow fangs that can envenomate normally, but also are so arranged that they can release a jet of venom into the eyes of a threatening predator from up to 2 metres distant, an action which produces intense pain and rapid blindness in the attacked animal, effectively putting it out of the fight. However, all venomous snakes will reserve
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