title: It's Not Easy Being Blue: Are There Olfactory and Visual Trade-Offs in Plant Signalling?
abstract: Understanding the signals used by plants to attract seed disperses is a pervasive quest in evolutionary and sensory biology. Fruit size, colour, and odour variation have long been discussed in the controversial context of dispersal syndromes targeting olfactory-oriented versus visually-oriented foragers. Trade-offs in signal investment could impose important physiological constraints on plants, yet have been largely ignored. Here, we measure the reflectance and volatile organic compounds of a community of Malagasy plants and our results indicate that extant plant signals may represent a trade-off between olfactory and chromatic signals. Blue pigments are the most visually-effective--blue is a colour that is visually salient to all known seed dispersing animals within the study system. Additionally, plants with blue-reflecting fruits are less odiferous than plants that reflect primarily in other regions of the colour spectrum.
authors.affiliation: Department of Anthropology, McGill University, Montreal, Quebec, Canada.
authors.forename: Kim
authors.initials: K
authors.lastname: Valenta
authors.affiliation: Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Kevin A
authors.initials: KA
authors.lastname: Brown
authors.affiliation: Department of Anthropology, Campus Box 1114, One Brooking Drive, Washington University, St. Louis, Missouri, United States of America.
authors.forename: Amanda D
authors.initials: AD
authors.lastname: Melin
authors.affiliation: Department of Biology, York University, Toronto, Ontario, Canada.
authors.forename: Spencer K
authors.initials: SK
authors.lastname: Monckton
authors.affiliation: Leibniz Institute for Tropospheric Research, Leipzig, Germany.
authors.forename: Sarah A
authors.initials: SA
authors.lastname: Styler
authors.affiliation: Department of Chemistry, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Derek A
authors.initials: DA
authors.lastname: Jackson
authors.affiliation: Department of Anthropology, McGill University, Montreal, Quebec, Canada.
authors.forename: Colin A
authors.initials: CA
authors.lastname: Chapman
mesh_terms: D000818:Animals; D005075:Biological Evolution; D003116:Color; D017753:Ecosystem; D005638:Fruit / Q000033:anatomy & histology / Q000145:classification / Q000502:physiology; D008270:Madagascar; D009812:Odorants; D010775:Photic Stimulation; D010802:Phylogeny; D010860:Pigments, Biological / Q000378:metabolism; D018521:Plant Physiological Phenomena; D010944:Plants / Q000033:anatomy & histology / Q000145:classification; D058614:Seed Dispersal / Q000235:genetics; D015398:Signal Transduction; D012903:Smell / Q000235:genetics; D055549:Volatile Organic Compounds / Q000032:analysis*
chemical_list: D010860:Pigments, Biological; D055549:Volatile Organic Compounds