DOI: 10.5061/dryad.2v6wwpzk3
title: Datasets - Evolutionary history, not ecogeographic rules, explains size variation of tropical insects along elevational gradients

description: One of the best-known biogeographic rules for ectotherms is the
 temperature-size rule, which asserts that ectotherms produce smaller
 adults at warmer temperatures. Although this is often true, it has become
 clear that there is no single process behind the pattern and many
 exceptions to the rule. To disentangle such complex temperature-size
 relationships, individual clades must be examined at ecological and
 evolutionary scales. We examined temperature-size relationships for 2106
 individuals from 64 populations and 40 species of Cephaloleia rolled-leaf
 beetles (Chrysomelidae; Cassidinae) occurring along two tropical
 elevational gradientss: Barva and the Talamanca Cordillera in Costa Rica,
 Central America. We tested whether the temperature-size rule applied to
 interspecific elevational assemblages, intraspecific elevational
 populations, or different rearing temperatures for individual populations.
 At the interspecific scale, evolutionary history, rather than elevation,
 explains body size. At the intraspecific scale, only one of seven species
 followed the temperature-size rule across elevations. When larvae were
 reared at different temperatures, only one of five populations followed
 the temperature-size rule. Most populations grew to a fixed size
 regardless of temperature. Size in Cephaloleia beetles is constrained by
 their evolutionary history and responds to factors that rarely correlate
 with temperature. As temperature increases, ectotherms will not
 universally shrink, but determining if and why their size will change will
 require further investigation. Here we provide the following datasets used
 to determine effects of temperature on insect body size at population and
 community levels: Supplement S1. Body length for 2106 individuals
 representing 64 populations from 40 species of Cephaloleia rolled-leaf
 beetle along the Barva and Talamanca elevational gradients, Costa Rica.
 Supplement S2. Intraspecific differences in length for 798 individuals
 from seven Cephaloleia species present at multiple life zone. Supplement
 S3. Effects of developmental temperatures on Cephaloleia adult size in 968
 individuals from four species and five populations reared in the
 laboratory at temperatures between 10 and 35 °C.
description: <strong>Record of <em>Cephaloleia</em>
 distributions and size</strong> We recorded elevational
 distributions of <i>Cephaloleia </i>species from 2005 to 2016.
 Beetles were collected on the Barva transect (eastern slope of the Central
 Cordillera 10° 0′–10° 26′ N, 83° 59′–84° 07′ W) and the western slope of
 the Talamanca Cordillera (8° 38′–8° 58′ N, 82° 50′–83° 05′ W). On the
 Barva transect, beetles were collected at La Selva Biological Station (50
 m a.s.l.) and transect shelters in Braulio Carrillo National Park (700,
 1070, 1500 and 2100 m a.s.l.). Collections on Talamanca were made between
 Ciudad Neily and Fila de Cal (60-400 m a.s.l.), as well as at Las Cruces
 Biological Station (1200 m a.s.l.) and in La Amistad National Park
 (1500-2100 m a.s.l.). Beetles from these sites were assigned to three wet
 forest life zones based on elevation: lowlands (0-499 m), premontane
 (500-1499 m), and montane (1500-2500 m). <i>Cephaloleia</i>
 beetles were identified using a combination of traditional taxonomy and
 DNA barcoding. The specimens were measured individually using Moticam
 software (Motic, Xiamen, China) and a calibrated Fisher digital dissecting
 microscope. <strong>Experiments testing
 the effects of temperature on body size</strong> We performed these experiments at
 La Selva Biological Station, Costa Rica from September 2017 to November
 2018. To test if temperature can directly influence adult size, we reared
 in the laboratory at multiple temperatures individuals of <i>C.
 belti</i> from lowland forests<i> </i>and<i> C.
 belti </i>from montane forests, as well as <i>C.
 </i>aff. <i>dilaticollis, C. </i>aff.
 <i>dorsalis</i>, and <i>C. placida</i> from
 lowland forests. For each population, wild males and females were
 collected, paired, fed <i>ad libitum </i>with young leaf
 tissue from each species’ most commonly used host plant, and given squares
 of mature leaf tissue for oviposition substrate. Every 48 h, eggs were
 removed from the leaf tissue, individually placed in containers lined with
 filter paper, and distributed among environmental chambers. At the
 beginning of the experiment, eggs were assigned to six temperatures: 10°C,
 15°C, 20°C, 25°C, 30°C, and 35°C. These temperatures range from the
 minimum temperature experienced in the montane forests to the predicted
 lowland maximum temperature in 2100. We measured adults the day after
 eclosion by photographing them with a digital camera (Diagnostic
 Instruments Inc. Model 3.2.0, Sterling Heights, MI, USA) attached to a
 stereoscope (Leica MZ 12s). We then estimated adult lengths from the
 photographs to the nearest 10<sup>-2 </sup>mm using the
 program SPOT V.3.5.8 (Diagnostic Instruments, Inc.).