DOI: 10.5061/dryad.pzgmsbcj0
title: Character displacement in the midst of background evolution in island populations of Anolis lizards: a spatiotemporal perspective

description: Negative interactions between species can generate divergent selection
 that causes character displacement. However, other processes cause similar
 divergence. We use spatial and temporal replication of island populations
 of Anolis lizards to assess the importance of negative interactions in
 driving trait shifts. Previous work showed that the establishment of
 Anolis sagrei drove resident Anolis carolinensis to perch higher and
 evolve larger toepads. To further test the interaction’s causality and
 predictability, we resurveyed a subset of islands nine years later. Anolis
 sagrei had established on one island between surveys. We found that A.
 carolinensis on this island now perch higher and have larger toepads.
 However, toepad morphology change on this island was not distinct from
 shifts on six other islands whose Anolis community composition had not
 changed. Thus, the presence of A. sagrei only partly explains A.
 carolinensis trait variation across space and time. We also find that A.
 carolinensis on islands with previously established A. sagrei now perch
 higher than a decade ago, and that current A. carolinensis perch height is
 correlated with A. sagrei density. Our results suggest that character
 displacement likely interacts with other evolutionary processes in this
 system, and that temporal data are key to detecting such interactions.
description: Please see the paper for details.
description: <strong>perch.height.southTwin.csv</strong>
 This is the 2019 perch height data set for South Twin and the
 other six islands. dstrb-yes means that the perch heigh of a lizard was
 likely changed by our presence. Tree height is the total height of the
 tree that the perch was on. as.int.sex notes whether one or more
 <em>A. sagrei</em> was "nearby" the perch and what
 their sex was/were; see main text for definition of nearby.
 <strong>101207_Mosquito Lagoon_Ecology
 Morphology_Master.csv</strong> This is the
 dataset collected in 2010 that is associated with Stuart et al (2014;
 Science). See the main text for the citation. as.int is, again, whether an
 A. sagrei was nearby. <strong>2019_toepad.csv
 & 2019_svl_mass.id.csv</strong> File 1 is
 the toepad data set for lizards captured in 2019 on South Twin and the six
 control islands. Each individual gets 2 rows, one for Left side and one
 for Right. File 2 is the mass, snout-vent length, and confirmed sex of
 every captured lizard in 2019.
 <strong>toes_male_female.csv</strong>
 This contains the lamella count and toepad area of lizards
 captured in 2010. It contains left side (".l"), right side
 (".r"), and average (".av"). Morph.good.av values of 1
 mean that the toepads were undamaged and images were collected well for
 both sides. SVL is also in this data set.
 <strong>catch.effort.southTwin.csv</strong>
 This is the result of the catch-per-unit effort survey for A
 sagrei density. One person walked islands for 1 hour in th emorning,
 noting the sex and perch height of Anolis sagrei.
 <strong>Dryad_Kamath_etal.R</strong>
 This is R script that will reproduce all tables, figures, and
 results from the paper. It calls on the data sets listed above.