title: The contribution of phenotypic plasticity to the evolution of insecticide tolerance in amphibian populations.
abstract: Understanding population responses to rapid environmental changes caused by anthropogenic activities, such as pesticides, is a research frontier. Genetic assimilation (GA), a process initiated by phenotypic plasticity, is one mechanism potentially influencing evolutionary responses to novel environments. While theoretical and laboratory research suggests that GA has the potential to influence evolutionary trajectories, few studies have assessed its role in the evolution of wild populations experiencing novel environments. Using the insecticide, carbaryl, and 15 wood frog populations distributed across an agricultural gradient, we tested whether GA contributed to the evolution of pesticide tolerance. First, we investigated the evidence for evolved tolerance to carbaryl and discovered that population-level patterns of tolerance were consistent with evolutionary responses to pesticides; wood frog populations living closer to agriculture were more tolerant than populations living far from agriculture. Next, we tested the potential role of GA in the evolution of pesticide tolerance by assessing whether patterns of tolerance were consistent with theoretical predictions. We found that populations close to agriculture displayed constitutive tolerance to carbaryl whereas populations far from agriculture had low naïve tolerance but high magnitudes of induced tolerance. These results suggest GA could play a role in evolutionary responses to novel environments in nature.
authors.affiliation: Department of Forestry and Natural Resources, Purdue University West Lafayette, IN, USA.
authors.forename: Jessica
authors.initials: J
authors.lastname: Hua
authors.affiliation: Department of Biological Sciences, Rensselaer Polytechnic Institute Troy, NY, USA.
authors.forename: Devin K
authors.initials: DK
authors.lastname: Jones
authors.affiliation: Department of Biological Sciences, Rensselaer Polytechnic Institute Troy, NY, USA.
authors.forename: Brian M
authors.initials: BM
authors.lastname: Mattes
authors.affiliation: Department of Biological Sciences, Southwestern Oklahoma State University Weatherford, OK, USA.
authors.forename: Rickey D
authors.initials: RD
authors.lastname: Cothran
authors.affiliation: Department of Biological Sciences, Rensselaer Polytechnic Institute Troy, NY, USA.
authors.forename: Rick A
authors.initials: RA
authors.lastname: Relyea
authors.affiliation: Department of Forestry and Natural Resources, Purdue University West Lafayette, IN, USA.
authors.forename: Jason T
authors.initials: JT
authors.lastname: Hoverman
keywords: Lithobates sylvaticus; acetylcholine esterase inhibitor; amphibian declines; genetic accommodation; phenotypic plasticity; toxicology