DOI: 10.5061/dryad.05qfttf3w
title: Data from: Can extreme climatic events induce shifts in adaptive potential? A conceptual framework and empirical test with Anolis lizards

description: Multivariate adaptation to climatic shifts may be limited by trait
 integration that causes genetic variation to be low in the direction of
 selection. However, strong episodes of selection induced by extreme
 climatic pressures may facilitate future population-wide responses if
 selection reduces trait integration and increases adaptive potential
 (i.e., evolvability). We explain this counter-intuitive framework for
 extreme climatic events in which directional selection leads to increased
 evolvability and exemplify its use in a case study. We tested this
 hypothesis in two populations of the lizard Anolis scriptus that
 experienced hurricane-induced selection on limb traits. We surveyed
 populations immediately before and after the hurricane as well as the
 offspring of post-hurricane survivors, allowing us to estimate both
 selection and response to selection on key functional traits: forelimb
 length, hindlimb length, and toepad area. Direct selection was parallel in
 both islands and strong in several limb traits. Even though overall limb
 integration did not change after the hurricane, both populations showed a
 non-significant tendency toward increased evolvability after the hurricane
 despite the direction of selection not being aligned with the axis of most
 variance (i.e., body size). The population with comparably lower
 between-limb integration showed a less constrained response to selection.
 Hurricane-induced selection, not aligned with the pattern of high trait
 correlations, likely conflicts with selection occurring during normal
 ecological conditions that favor functional coordination between limb
 traits, and would likely need to be very strong and more persistent to
 elicit a greater change in trait integration and evolvability. Future
 tests of this hypothesis should use G-matrices in a variety of wild
 organisms experiencing selection due to extreme climatic events. 
description: SVL was measured from the tip of the snout to the posterior edge
 of the anal scale (Herrel et al. 2008); femur length was measured from the
 axilla to the tip of the femur; humerus length from the base (detected by
 palpation) to the tip of the humerus; tibia length was measured from the
 femoro-tibial joint to the tibia-metatarsus joint; ulna length was
 measured from the humero-ulnar joint to the ulna-metacarpus joint;
 metatarsus length was measured from the proximal-most part of the
 metatarsus to the base of the longest toe; metacarpus length was measured
 from the proximal-most part of the metacarpus to the base of the longest
 toe; longest toe length was measured from the base to the tip of the toe
 for both the hand and the foot, not including the claw. All measurements
 were taken using digital calipers (MitutoyoCD-20DC, Japan; precision: 0.01
 mm), and were taken on the left side of the specimens. Toepad surface area
 was quantified using a Moment Macro Lens attachment on an iPhone 7. In the
 field, we took a picture of the forefoot and hindfoot of each lizard.
 Later, CMD measured the surface area of toepads on digit III on the
 forelimb and digit IV on the hindlimb to the first scale after the toepad
 widens (see Donihue et al. 2020), using ImageJ (version 1.51a; W. Rasband,
 National Institutes of Health, Bethesda, MD). All measurements are in log
 scale.
description: main_data.rda: open using function 'load' in R
 programming environment. water_data.csv: open using a
 Excel or a text editor (e.g., Notepad). pine_data.csv:
 open using Excel or a text editor (e.g., Notepad).