By Susan Milius
A South African scorpion economizes as it stings, injecting a simple mix first, followed by a venom that’s more complicated to produce.
The first droplet from the stinger of the Parabuthus transvaalicus scorpion consists mostly of a strong, toxic solution of potassium, says Bruce Hammock of the University of California, Davis. Only afterward does the scorpion release a cocktail of proteins and some 100 peptides, Hammock, Bora Inceoglu, and their UC-Davis colleagues report in an upcoming Proceedings of the National Academy of Sciences.