Picrotoxanes occurrence

Systematic and Geographic Occurrence of Picrotoxane-Containing Plants... 

How can this scattered taxonomic occurrence of the picrotoxanes be explained Many of the apparent chemical convergences in animal toxins have been explained as toxins received via the food chain e.g. brevetoxin, pederin, saxitoxin, tetrodo-toxin, and the toxins of the arrow-poison frogs). This may explain the occurrence of picrotoxanes in both parasitic animals and plants, but further research will be necessary for a better understanding of this phenomenon. 

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