DOI: 10.5061/dryad.1q389
title: Data from: Latitudinal patterns of phenology and age-specific thermal performance across six Coenagrion damselfly species

description: Using a combination of computer simulations and laboratory experiments we
 test if the thermal sensitivity of growth rates change during ontogeny in
 damselfly larvae and if these changes can be predicted based on the
 natural progression of average temperature or thermal variability in the
 field. The laboratory experiment included replicated species from
 Southern, Central and Northern Europe. Although annual fluctuations in
 temperature represent a key characteristic of temperate environments, few
 studies of thermal performance have considered the ecological importance
 of the studied traits within a seasonal context. Instead, thermal
 performance is assumed to remain constant throughout ontogeny and reflect
 selection acting over the whole life cycle. The laboratory experiment
 revealed considerable variation among species in the strength and
 direction of ontogenetic performance shifts. In four species from Southern
 and Central Europe, reaction norms were steepest during early ontogeny,
 becoming less steep during later ontogenetic stages (indicative of
 low-temperature acclimation). In one Northern European species, the slope
 of reaction norms did not change during ontogeny. In the other North
 European species, reaction norms became steeper during ontogeny
 (indicative of high-temperature acclimation). We had expected
 high-latitude species to show strong low-temperature acclimation
 responses, because they have a short flight season and inhabit a strongly
 seasonal environment. Instead, we found the reversed pattern low-latitude
 species displayed strong low-temperature acclimation responses and
 high-latitude species displayed weak, or even reversed, acclimation
 responses to low temperatures. These findings suggest that low-temperature
 acclimation may be less beneficial and possibly more costly in habitats
 with rapid seasonal transitions in average temperature. We conclude that
 thermal performance traits are more dynamic than typically assumed and
 caut ion against using results from single ontogenetic stages to predict
 species' responses to changing environmental conditions.
description: Changes in
 temperature-specific growth rates across ontogeny in damselfly
 larvaeGrowth rates
 ("gr") of larvae of six species of damselflies reared in the
 laboratory at three or four temperatures ("temp"). Growth rates
 represent size-corrected relative growth rates (in the unit off mm
 increase in headwidth/day; the size-correction was done using Equation 8
 in the corresponding article) estimated during early (day 0-42),
 intermediate (day 42-84) and late ontogeny (day
 84-126)("period").NilssonOrtman_RGRdata.xlsxPhenological data on the start and end of the flight season of European damselfliesData on the day of the year when the flight season of 15 European species of damselfies start ("Spring") and end ("Fall") based on literature records. Literature refererence IDs ("Ref") correspond to numbers used in Appendix B of the corresponding article and the records are graded from 1 to 4 based on their quality ("Quality"), with 4 being the most reliable.Phenologydata.xlsx