Evolution: Fangtastic Venoms Underpin Parasitic Mimicry

Abstract

DispatchEvolution: Fangtastic Venoms Underpin Parasitic Mimicry Venomous teeth are rare in fishes, which typically utilise spines for defence. A new study reveals the evolutionary origins of fangs and venom in the Nemophini blennies and shows that in contrast to snakes and lizards, the fangs pre-date the venom. Some groups such as the snakes and the spiders have evolved oral delivery systems (fangs), whereas others have evolved stingers (wasps and scorpions), modified venomous legs (centipedes) or stinging tentacles (cnidarians). In many cases, these venoms are also used for self-defence. Scorpions for example, can inject two different venoms -one for self-defence, which is painful but metabolically cheap and one for prey incapacitation, which is protein rich and metabolically expensive [3]. Other organisms have evolved venoms solely to deter attacks on themselves. For example, many fishes have venomous fin spines or barbs, echinoderms (starfish and sea urchins) have venomous spines, ants have venomous stings or sprays and some moth and butterfly larvae have modified setae (urticating hairs).

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