DOI: 10.5061/dryad.8c94g44
title: Data from: Testing the geographical dimensions of genetic diversity following range expansion in a North American snake

description: Spatial and demographic expansion can alter patterns of genetic variation
 and have predictable spatial and temporal consequences. Two-dimensional
 range expansion should result in genetic variation that is correlated with
 the geographical axis of expansion. Notably, populations across the range
 of a geographically widespread species may asynchronously experience
 expansion and contraction events. We tested for the genetic consequences
 of range expansion in the flat-headed snake, Tantilla gracilis, which
 inhabits the North American Great Plains, which has few barriers to
 terrestrial dispersal. We sequenced mitochondrial (mtDNA) and nuclear DNA
 from across the range of T. gracilis, inferred phylogenies, and
 constructed haplotype networks. We observed multiple geographically
 circumscribed mtDNA clades that varied greatly in their spatial extent,
 but little range-wide variation in nuclear DNA. Mitochondrial sequence
 variation was negatively associated with latitude across their geographic
 range, the expected pattern of northward expansion. Finally, the three
 largest mtDNA clades exhibited varying demographic patterns, with only one
 consistent with recent expansion. Despite substantial mtDNA cladogenesis,
 the predicted signature of northern range expansion was still detectable
 in T. gracilis. Our results bolster the notion that Post-Pleistocene range
 expansion was a dominant force shaping the genetic diversity of
 vertebrates in central North America.
description: Tantilla_ND4CytB_phylogeographyAlighnment file containing NADH dehydrogenase subunit 4 (ND4) and flanking tRNAs (685 bp) concatenated with cytochrome b (cyt-b, 666 bp) for Conopsis biserialis, Coluber constrictor, Tantilla nigriceps (2 samples), T. wilcoxi (2 samples), T. relicta, T. coronata (2 samples), T. planiceps, and T. gracilis (77 samples). Each sequence id has a unique numerical ID for each sample. See associated manuscript (Table 1) for additional information for each sample.Tantilla_BDNF_gracilis_prunedAlignment file containing sequence (421 bp) of brain derived neurotropic factor (BDNF) for Tantilla wilcoxi (2 samples), T. coronata (3 samples), and T. gracilis (19 samples). Each sequence id has the unique numerical id for each sample. See associated manuscript (Table 1) for additional information for each sample.Tantilla_rag1_gracilis_prunedAlignment file containing sequence (478 bp) of recombination activating gene 1 (RAG-1) for Tantilla wilcoxi, T. coronata, T. relicta, T. nigriceps (2 samples), and T. gracilis (20 samples). Each sequence id has the unique numerical id for each sample. See associated manuscript (Table 1) for additional information for each sample.Tantilla_SNCAIP_gracilis_prunedAlignment file containing sequence (261 bp) of synuclein alpha interacting protein (SNCAIP) for Tantilla wilcoxi, T. coronata (3 samples), T. nigriceps, and T. gracilis (21 samples). Each sequence id has the unique numerical id for each sample. See associated manuscript (Table 1) for additional information for each sample.