title: Functional mismatch in a bumble bee pollination mutualism under climate change.
abstract: Ecological partnerships, or mutualisms, are globally widespread, sustaining agriculture and biodiversity. Mutualisms evolve through the matching of functional traits between partners, such as tongue length of pollinators and flower tube depth of plants. Long-tongued pollinators specialize on flowers with deep corolla tubes, whereas shorter-tongued pollinators generalize across tube lengths. Losses of functional guilds because of shifts in global climate may disrupt mutualisms and threaten partner species. We found that in two alpine bumble bee species, decreases in tongue length have evolved over 40 years. Co-occurring flowers have not become shallower, nor are small-flowered plants more prolific. We argue that declining floral resources because of warmer summers have favored generalist foraging, leading to a mismatch between shorter-tongued bees and the longer-tubed plants they once pollinated.
authors.affiliation: Biological Sciences Department, Natural Sciences Building Rm NS247, SUNY College at Old Westbury, Old Westbury, NY 11568, USA. Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA. nmillstrutt@gmail.com.
authors.forename: Nicole E
authors.initials: NE
authors.lastname: Miller-Struttmann
authors.affiliation: Department of Biology, Appalachian State University, Boone, NC 28608, USA.
authors.forename: Jennifer C
authors.initials: JC
authors.lastname: Geib
authors.affiliation: Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA.
authors.forename: James D
authors.initials: JD
authors.lastname: Franklin
authors.affiliation: School of Environmental Sciences, University of Guelph, Guelph, ON, Canada N1G 2W1.
authors.forename: Peter G
authors.initials: PG
authors.lastname: Kevan
authors.affiliation: Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA.
authors.forename: Ricardo M
authors.initials: RM
authors.lastname: Holdo
authors.affiliation: Department of Plant Biology, Michigan State University, East Lansing, MI 48824, USA.
authors.forename: Diane
authors.initials: D
authors.lastname: Ebert-May
authors.affiliation: Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA.
authors.forename: Austin M
authors.initials: AM
authors.lastname: Lynn
authors.affiliation: Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA. Department of Biological Sciences, Zoology Program, North Carolina State University, Raleigh, NC 27695, USA.
authors.forename: Jessica A
authors.initials: JA
authors.lastname: Kettenbach
authors.affiliation: Department of Life and Physical Sciences, Lincoln University, Jefferson City, MO 65101, USA.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Hedrick
authors.affiliation: Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA.
authors.forename: Candace
authors.initials: C
authors.lastname: Galen
mesh_terms: D000818:Animals; D001516:Bees / Q000033:anatomy & histology / Q000502:physiology*; D005075:Biological Evolution; D057231:Climate Change; D035264:Flowers / Q000033:anatomy & histology / Q000502:physiology*; D054817:Pollination; D013559:Symbiosis; D014059:Tongue / Q000033:anatomy & histology / Q000502:physiology*