CHIRAL SEX CUES

Abstract

FOR SEVERAL MONTHS EACH year, male elephants emit a message-laden chemical secretion from glands above their cheeks. It's part of an annual social phase known as musth, a time of pumped-up aggression and sexual activity for males at or beyond their teen years. Animal communications researcher L. Elizabeth L. Rasmussen of Oregon Health & Science University, Beaverton, has for years been teasing apart the musth messages in Asian elephants, and now she and her colleagues have uncovered a chemical subtlety with powerful social consequences ( Nature 2005, 438 ,1097). Males in musth emit mirror-image forms, or enantiomers, of the pheromone known as frontalin, which was first identified in 1969. Rasmussen's team has found that male Asian elephants, as they mature and as they progress through musth each year, emit frontalin enantiomers in changing ratios. The researchers harvested musth secretions from more than 100 elephants at different locations by gently pressing on the cheeks ...