The origin and evolution of social insect queen pheromones: Novel hypotheses and outstanding problems.
Queen pheromones, which signal the presence of a fertile queen and induce daughter workers to remain sterile, are considered to play a key role in regulating the reproductive division of labor of insect societies. Although queen pheromones were long thought to be highly taxon-specific, recent studies have shown that structurally related long-chain hydrocarbons act as conserved queen signals across several independently evolved lineages of social insects. These results imply that social insect queen pheromones are very ancient and likely derived from an ancestral signalling system that was already present in their common solitary ancestors. Based on these new insights, we here review the literature and speculate on what signal precursors social insect queen pheromones may have evolved from. Furthermore, we provide compelling evidence that these pheromones should best be seen as honest signals of fertility as opposed to suppressive agents that chemically sterilize the workers against their own best interests.
Department of Biology, Laboratory of Socioecology & Social Evolution, University of Leuven, Leuven, Belgium.
Cintia A
CA
Oi
Department of Biology, Laboratory of Socioecology & Social Evolution, University of Leuven, Leuven, Belgium.
Jelle S
JS
van Zweden
Department of Biology, Laboratory of Socioecology & Social Evolution, University of Leuven, Leuven, Belgium.
Ricardo C
RC
Oliveira
Department of Biology, Laboratory of Socioecology & Social Evolution, University of Leuven, Leuven, Belgium.
Annette
A
Van Oystaeyen
Departamento de Biologia da Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Brazil.
Fabio S
FS
Nascimento
Department of Biology, Laboratory of Socioecology & Social Evolution, University of Leuven, Leuven, Belgium.
Tom
T
Wenseleers
D000818:Animals; D005075:Biological Evolution; D007301:Insect Hormones / Q000502:physiology*; D007313:Insecta / Q000502:physiology*; D012098:Reproduction; D012724:Sex Attractants / Q000502:physiology*
D007301:Insect Hormones; D012724:Sex Attractants
cuticular hydrocarbons; fertility signals; queen pheromones; reproductive conflict; reproductive division of labour; social Hymenoptera; social evolution