DOI: 10.5061/dryad.3xsj3tx9v
title: Repeated evolution of terrestrial lineages in a continental lizard radiation

description: The ‘early-burst’ model of adaptive radiation predicts an early increase
 in phenotypic disparity concurrent with lineage diversification. Although
 most studies report a lack of this coupled pattern, the underlying
 processes are not identified. The continental radiation of
 &lt;i&gt;Hemidactylus&lt;/i&gt; geckos from Peninsular
 India includes morphologically diverse species that occupy various
 microhabitats. This radiation began diversifying ~36 Mya with an early
 increase in lineage diversification. Here, we test the ‘early-burst’
 hypothesis by investigating the presence of ecomorphs and examining the
 pattern of morphological diversification in a phylogenetic framework. Two
 ecomorphs— terrestrial and scansorial species— that vary significantly in
 body size and toepad size were identified. Unlike the prediction of the
 ‘early-burst’ model, we find that disparity in toepad morphology
 accumulated more recently ~14 Mya and fit the OU model. Ancestral state
 reconstruction of the two ecomorphs demonstrates that terrestrial lineages
 evolved independently at least five times from scansorial ancestors, with
 the earliest diversification in terrestrial lineages 19–12 Mya. Our study
 demonstrates a delayed increase in morphological disparity as a result of
 the evolution of terrestrial ecomorphs. The diversification of terrestrial
 lineages is concurrent with the establishment of open habitat and
 grasslands in Peninsular India, suggesting that the appearance of this
 novel resource led to the adaptive diversification.
description: This dataset includes 42 morphological measurements from
 preserved specimens. Data on 33 specimens were included from published
 literature (Agarwal, Giri, & Bauer, 2011; Gaikwad, Kulkarni,
 Bhambure, & Giri, 2009; Giri, 2008; Giri & Bauer, 2006;
 Giri & Bauer, 2008; Mirza & Sanap, 2014; Murthy, Bauer,
 Lajmi, Agarwal, & Giri, 2014). The following traits were measured
 to capture the differences in size, body shape, head shape and shape of
 the lamellar pad size: snout to vent length (SVL); body
 shape: trunk length (TRL), body width (BW), tail length (TL), width at
 tail base (TW), height of the tail at the base (TD), head length (HL),
 head width (HW), head height (HH), crus length (CL) and forearm length
 (FL); head shape: orbital diameter (OD), distance from eye to nostril
 (NE), distance from eye to tip of snout (OrbS), distance between eye and
 ear (OrbEar), length of the ear opening (EarL), distance between the
 nostrils (IN), intraorbital distance (IO), distance between ear and snout
 (EarS), length and width of the rostral scale (RosL and RosW), and length
 and width of the mental scale (MenL and MenW); and shape of the lamellar
 pad: length of the forelimb and hindlimb toepads (LFL1, LFL2, LFL3, LFL4,
 LFL5, LHL1, LHL2, LHL3, LHL4, LHL5) and width of the forelimb and hindlimb
 toepads (WFL1, WFL2, WFL3, WFL4, WFL5, WHL1, WHL2, WHL3, WHL4, WHL5). The
 toepad measurements were taken under a Leica stereomicroscope using a
 scale and later measured using the software ImageJ. Museum specimens were
 measured using photographs of the toepads along with a scale.