DOI: 10.5061/dryad.70rxwdbvp
title: Datasets for Mixed support for gene flow as a constraint to local adaptation and contributor to the limited geographic range of an endemic salamander

description: Understanding mechanisms that underlie species range limits is at the core
 of evolutionary ecology. Asymmetric gene flow between larger core
 populations and smaller edge populations can swamp local adaptation at the
 range edge and inhibit further range expansion. However, empirical tests
 of this theory are exceedingly rare. We tested the hypothesis that
 asymmetric gene flow can constrain local adaptation and thereby species’
 range limits in an endemic US salamander (Ambystoma barbouri) by
 determining if gene flow is asymmetric between the core and peripheries of
 the species’ geographic distribution and testing whether local adaptation
 is swamped at range edges with a reciprocal transplant experiment. Using
 putatively neutral loci from populations across three core-to-edge
 transects that covered nearly the entire species’ geographic range, we
 found evidence for asymmetric, core-to-edge gene flow along western and
 northern transects, but not along a southern transect. Subsequently, the
 reciprocal transplant experiment suggested that northern and western edge
 populations are locally adapted despite experiencing asymmetric gene flow
 yet have lower fitness in their respective home regions than center
 populations do. Conversely, southern populations exhibit low deme quality,
 experiencing high mortality regardless of where they were reared, likely
 due to harsher edge habitat conditions. Consequently, we provide rare
 species-wide evidence that local adaptation can occur despite asymmetric
 gene flow, though migration from the core may prohibit range expansion by
 reducing fitness in edge populations. Further, our multi-transect study
 shows that multiple, non-mutually exclusive mechanisms can lead to range
 limits within a single species.
description: Data originate from field notes. Contained within are detailed
 measurements and observations from four transplantation cites in Kentucky
 and Ohio, US.
description: dTable1: Diversity and genetic measurements for each collection
 stream using a subset of invidividuals. N = number of individuals, AR =
 allelic richness, Ho = observed heterozygosity, He = expected
 heterozygosity, ID = geo identification, Fis = inbreeded coefficient (+
 highest and lowest value). dTable2: Details of each
 metamorph collected from the experiment. Region = transplantation regions
 (Center, South, North, West), Position = block position, Cont. ID =
 container ID, Mass (g) = dry metamorph mass, Date = date of metamorphosis,
 TL = total length of metamorph, SVL = snout-vent length of metamorph, Gape
 = gape of metamorph. dTable3: Water and air logger data
 from each site. Each transplantation site has the water temperature, light
 intensity, and air temperature for the entirety of the
 experiment.  dTable4: Randomized block experiment
 design. Mapping of blocks and experimental setup for each transplantation
 site (tabs). dTable5: Raw field notes for each visit to
 transplantation sites. Date of visit, transplantation site, block,
 remaining salamanders in container, total dissolved solutes, water pH,
 number of Dead salamanders observed, picture of salamanders, Notes, mass
 of salamanders. dTable6: Input data for survival
 analysis. Each row indicates a dead salamader, obs is the number of days
 until death, treatment = transplantation treatment (center in center,
 south in center, west in center, etc.).