ENCORE  We all get defensive sometimes.  For some animals, evolution has provided a highly effective mechanism for saying “back off!”.  A puncture by a pair of venom-filled fangs gets the point across nicely.  But one animal’s poison may be another’s cure.  Some dangerous critters churn out compounds that can be synthesized into life-saving drugs. Meet the spiny, fanged, and oozing creatures who could help defend us against such illnesses as hypertension and kidney disease.  Plus, the King of Pain - a scientist who has been stung by more than 80 species of insects in his pursuit of a better understanding of venom’s biochemistry.  Find out which winged stinger scored the highest on his pain index.    And, why the drug we need most may come from the quietest members of the biosphere: turning to plants for a new generation of antibiotics.  Guests: Owen Maercks – Co-owner, East Bay Vivarium, Berkeley, California  Justin Schmidt – Entomologist, University of Arizona, author of “The Sting of the Wild: The Story of the Man Who Got Stung for Science” Christie Wilcox – author of “Venomous: How Earth’s Deadliest Creatures Mastered Biochemistry”  Cassandra Quave – Ethnobotanist, assistant professor of dermatology, herbarium curator, Emory University