DOI: 10.5061/dryad.6m905qg86
title: Data from: Climate mediates the tradeoffs associated with phenotypic plasticity in an amphibian polyphenism

description: Polyphenisms occur when phenotypic plasticity produces morphologically
 distinct phenotypes from the same genotype. Plasticity is maintained
 through fitness tradeoffs which are conferred to different phenotypes
 under specific environmental contexts. Predicting the impacts of
 contemporary climate change on phenotypic plasticity is critical for
 climate sensitive animals like amphibians, but elucidating the selective
 pressures maintaining polyphenisms requires a framework to control for all
 mechanistic drivers of plasticity. Using a 32-year dataset documenting the
 larval and adult histories of 717 Arizona tiger salamanders (Ambystoma
 mavortium nebulosum), we determined how annual variation in climate and
 density-dependence explained the maintenance of two distinct morphs
 (terrestrial metamorph vs. aquatic paedomorph) in a high-elevation
 polyphenism. The effects of climate and conspecific density on morph
 development was evaluated with piecewise structural equation models (SEM)
 to tease apart the direct and indirect pathways by which these two
 mechanisms affect phenotypic plasticity. Climate had a direct effect on
 morph outcome whereby longer growing seasons favored metamorphic outcomes.
 Also, climate had indirect effects on morph outcome as mediated through
 density-dependent effects, such as long overwintering coldspells
 corresponding to high cannibal densities and light snowpacks corresponding
 to high larval densities; both of which promoted paedomorphic outcomes.
 Both climate and density-dependence serve as important proxies for growth
 and resource limitation, which are important underlying drivers of the
 phenotypic plasticity in animal polyphenisms. Our findings motivate new
 studies to determine how contemporary climate change will alter the
 selective pressures maintaining phenotypic plasticity and polyphenisms.
description: See published manuscript for detailed methods.
description: **README FOR THE CSV DATA FILE (Salamander SEM_Data)** * **Data on the
 adult and larval histories of 717 salamanders** Unique ID's Unique
 identifier of individual salamanders based on toe clips or PIT tags Pond
 Origin Pond of larval development Morph Adult developmental (Meta, Paedo)
 Morph1 Binary expression of adult morph development (1, 0) Cohort Year of
 birth Sex Male or Female Age First Repro Age of first known reproduction
 Max. Age Longevity No. Breeding Years Number of years the animal was
 observed in a breeding state Larval.Age Age of the larvae when captured
 (years) Larval.SVL SVL of the larvae when captured (mm) Pond.SVL Average
 SVL of all larvae in a pond (mm) Relative.SVL SVL of the larvae when
 captured relative to the SVL of all other larvae in the pond (mm)
 Larval.Cond Body condition (mass/SVL) of the larvae when captured
 Larval.Year Year that the larvae was captured * **Environmental conditions
 experienced by the 717 salamanders during their larval lifetime
 development** Average.Coldspell.Corrected Average annual coldspell
 conditions experienced by a salamander during it's larval development
 Average.Cannibal.Density Average annual cannibal densities experienced by
 a salamander during it's larval development Average.Larval.Density
 Average annual larval densities experienced by a salamander during
 its's larval development Average.GDD.Corrected Average annual number
 of growing degree days during the summer season experienced by a
 salamander during it's larval development Average.CumSnow.Corrected
 Average annual snowpack levels experienced by a salamander during
 its's larval development