Wrong poison

Natural History, Dec, 2005 by Daniel Levitis, Robert George Sprackland

In his article "Toxic Treasure" [10/05], Robert George Sprackland writes that tetrodotoxin "also turned up in the feathers of two genera of birds.... The source of the toxin turned out to be bacterial." My doctoral research focuses on those two genera; the birds carry batrachotoxin, not tetrodotoxin, a very different chemical. Tetrodotoxin is produced by various organisms, including bacteria, but there is no evidence that bacteria produce batrachotoxin. In fact, no one yet knows where the birds get their toxins.

Daniel Levitis

Berkeley, California

ROBERT GEORGE SPRACKLAND

REPLIES: Daniel Levitis is correct: the toxin that occurs in the two bird genera is batrachotoxin, which is commonly found in the skin of some Central and South American flogs. My main point remains, nonetheless, that many toxins can be found across a very broad and disparate range of creatures.