| Title: | Signaling from below: rodents select for deeper fruiting truffles with stronger volatile emissions |
| Author(s): | Stephens RB; Trowbridge AM; Ouimette AP; Knighton WB; Hobbie EA; Stoy PC; Rowe RJ; |
| Address: | "Natural Resources and the Environment, University of New Hampshire, 114 James Hall, 56 College Road, Durham, New Hampshire, 03824, USA. Department of Entomology, University of Wisconsin, Madison, Wisconsin, 53706, USA. Earth Systems Research Center, University of New Hampshire, Morse Hall, 8 College Road, Durham, New Hampshire, 03824, USA. Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana, 59717, USA. Department of Biological Systems Engineering, University of Wisconsin, Madison, Wisconsin, 53706, USA" |
| ISSN/ISBN: | 1939-9170 (Electronic) 0012-9658 (Linking) |
| Abstract: | "Many plant and fungal species use volatile organic compounds (VOCs) as chemical signals to convey information about the location or quality of their fruits or fruiting bodies to animal dispersers. Identifying the environmental factors and biotic interactions that shape fruit selection by animals is key to understanding the evolutionary processes that underpin chemical signaling. Using four Elaphomyces truffle species, we explored the role of fruiting depth, VOC emissions, and protein content in selection by five rodent species. We used stable isotope analysis of nitrogen (delta(15) N) in truffles to estimate fruiting depth, proton-transfer-reaction mass spectrometry to determine volatile emission composition, and nitrogen concentrations to calculate digestible protein of truffles. We coupled field surveys of truffle availability with truffle spore loads in rodent scat to determine selection by rodents. Despite presumably easier access to the shallow fruiting species, E. americanus (0.5-cm depth) and E. verruculosus (2.5-cm depth), most rodents selected for truffles fruiting deeper in the soil, E. macrosporus (4.1-cm depth) and E. bartlettii (5.0-cm depth). The deeper fruiting species had distinct VOC profiles and produced significantly higher quantities of odiferous compounds. Myodes gapperi (southern red-backed vole), a fungal specialist, also selected for truffles with high levels of digestible protein, E. verruculosus and E. macrosporus. Our results highlight the importance of chemical signals in truffle selection by rodents and suggest that VOCs are under strong selective pressures relative to protein rewards. Strong chemical signals likely allow detection of truffles deep within the soil and reduce foraging effort by rodents. For rodents that depend on fungi as a major food source, protein content may also be important in selecting truffles" |
| Keywords: | Animals;Animals *Ascomycota Fruit Rodentia *Volatile Organic Compounds Elaphomyces chemical ecology communication fungal interactions fungal volatiles fungivory mammal truffle volatile organic compounds; |
| Notes: | "MedlineStephens, Ryan B Trowbridge, Amy M Ouimette, Andrew P Knighton, W Berk Hobbie, Erik A Stoy, Paul C Rowe, Rebecca J eng 0229197 & 1006881/New Hampshire Agricultural Experiment Station/International DE-SC0010845/U.S. Department of Energy Office of Science (BER)/International North American Truffling Society/International Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. 2019/12/25 Ecology. 2020 Mar; 101(3):e02964. doi: 10.1002/ecy.2964. Epub 2020 Jan 23" |
