The ecology and evolution of fly dispersed dung mosses (Family Splachnaceae): Manipulating insect behaviour through odour and visual cues
- Cite this article as:
- Marino, P., Raguso, R. & Goffinet, B. Symbiosis (2009) 47: 61. doi:10.1007/BF03182289
The use of sensory attractants is central to most animal-mediated pollination and seed dispersal interactions. Approximately half the 73 species of mosses’ in the family Splachnaceae are entomophilous (have their spores dispersed by flies) and are coprophilous (grow on feces and carrion). When mature, entomophilous species often produce brightly coloured, scented sporophytes which, for several species, have been shown to attract flies. In a number of cases, sporophyte colours and odours, as well as the flies that visit them, have been shown to be species-specific, suggesting that the mosses co-exist by signal diversification, just as flowering plants are thought to reduce competition for pollinators. Analyses of scent chemistry identified an odour contrast between generations; gametophytes were either unscented or weakly scented in most species, whereas sporophyte odours were universally stronger per unit mass and much more chemically complex. Sporophyte odours of North and South American species sampled were both complex and diverse, with an apparent inverse relationship between the size and showiness of the apophysis and its odour complexity. Furthermore, phylogenetic evidence suggests that fly dispersal of spores through visual and olfactory signals has evolved multiple times in the Splachnaceae and that modifications of sporophyte morphology may have followed, rather than triggered, the transitions to coprophily and entomophily. We review the ecological and evolutionary aspects ofentomophily, with particular emphasis on the chemistry of sporophyte odours and the means by which they mimic decaying organic matter.