An Antiaphrodisiac in Heliconius melpomene Butterflies

Abstract

Gilbert (1976) suggested that male-contributed odors of mated females of Heliconius erato could enforce monogamy. We investigated the pheromone system of a relative, Heliconius melpomene, using chemical analysis, behavioral experiments, and feeding experiments with labeled biosynthetic pheromone precursors. The abdominal scent glands of males contained a complex odor bouquet, consisting of the volatile compound (E)-beta-ocimene together with some trace components and a less volatile matrix made up predominately of esters of common C16- and C18-fatty acids with the alcohols ethanol, 2-propanol, 1-butanol, isobutanol, 1-hexanol, and (Z)-3-hexenol. This bouquet is formed during the first days after eclosion, and transferred during copulation to the females. Virgin female scent glands do not contain these compounds. The transfer of ocimene and the esters was shown by analysis of butterflies of both sexes before and after copulation. Additional proof was obtained by males fed with labeled D-13C6- glucose. They produced 13C-labeled ocimene and transferred it to females during copulation. Behavioral tests with ocimene applied to unmated females showed its repellency to males. The esters did not show such activity, but they moderated the evaporation rate of ocimene. Our investigation showed that beta-ocimene is an antiaphrodisiac pheromone of H. melpomene.

The Functional Basis of Wing Patterning inHeliconiusButterflies: The Molecules Behind Mimicry

“…The nutritional benefit provided by pollen feeding has significant impacts on many aspects of Heliconius biology, such as cyanogenesis, reproduction, and longevity (Dunlap-Pianka et al 1977;Brown et al 1991). Other notable aspects of Heliconius biology include home-range behavior (Mallet 1986 a,b;Gilbert 1991), male production of specialized "anti-aphrodisiac" compounds (Gilbert 1976;Schulz et al 2007Schulz et al , 2008, the unique pupal-mating behavior of some Heliconius species (Deinert et al 1994;, and their pronounced visual acuity (Zaccardi et al 2006), which is in part a product of a Heliconius-specific UV opsin duplication Yuan et al 2010).…”

Chromatography with silver nitrate: part 2

“…Schulz et al discovered that the male Heliconius melpomene butterfly relies on 43 as an anti-aphrodisiac pheromone during courtship. 45 To confirm the structure of 43 a 7:3 mixture of (Z)-and (E)-ocimene was prepared, with the amount of (E)-isomer being elevated to a 4:6 Z/E ratio using SNIS. A later report from the same group disclosed an E selective route to 43 starting from 44 (Scheme 2).…”

The benefit of being a social butterfly: communal roosting deters predation

“…Although the adaptive consequences of roosting remain unclear, it is unlikely that aggregations are involved with thermoregulation [10], kin selection [13] or mating (females usually mate once in their lifetime, within hours or days after eclosion) [30,31]. The favoured explanations have been narrowed to two major hypotheses: information sharing and/or anti-predator defence.…”