DOI: 10.5061/dryad.mv2tk97
title: Data from: Getting chased up the mountain- high elevation may limit performance and fitness characters in a montane insect

description: 1. Climate change is expected to shift species distributions as
 populations grow in favorable habitats and decline in harsh ones. Montane
 animals escape warming conditions at low elevation by moving upslope, but
 may be physiologically constrained by conditions there. Effects of
 elevation were studied for montane populations of the leaf beetle
 Chrysomela aeneicollis, where allele frequencies at nuclear genes and the
 mitochondrion vary along latitudinal and altitudinal gradients. 2. A
 population presence survey conducted along a steep altitudinal transect
 (1600-3800 m) from 1981 to 2018 revealed that populations expand to low
 elevation following wet winters and retreat during drought. Quantitative
 surveys of a 45-site population network conducted from 2012-2018 along
 multiple altitudinal transects shows that when beetles are abundant,
 population size peaks at 3135 m, highest altitude populations are at the
 southern edge of the range, and populations decline and extirpate during
 drought, especially at low elevation. 3. To examine effects of elevation
 on measures of performance and fitness, beetles from a
 genetically-introgressed population (Bishop Creek- BC) were examined. In
 nature, fecundity of females transplanted along natural altitudinal
 transects was measured, as was thorax cytochrome c oxidase (CytOx)
 activity. To examine effects of environmental hypoxia independent of other
 factors limiting persistence at high elevation, development rate and
 activity of malate dehydrogenase (MDH) were measured for larvae reared
 under otherwise common garden conditions at low (1250 m) and high (3800 m)
 elevation. 4. In nature, fecundity declined with increasing elevation,
 independent of air temperature. CytOx activity was higher at high than low
 elevation, especially for individuals possessing genotypes of southern
 origin. Laboratory-reared larvae with southern mitochondrial haplotypes
 developed equally well at both elevations, but larvae with northern
 haplotypes developed more slowly at high elevation. MDH activity showed a
 similar pattern, suggesting that slower development rates at high
 elevation may be due to reduction in metabolic rate. 5. These findings
 suggest that physiological effects of environmental hypoxia may contribute
 to other factors known to restrict insects’ ability to persist at high
 elevation, ultimately disrupting associated ecological communities.
 However, some populations may possess genetic variation that allows for
 local adaption to high elevation.
description: FIG 1. Beetle elevation
 limits and site snow depthThis is an Excel file
 that contains data from Fig 1. Fig 1A data were determined from long-term
 population surveys in Big Pine Canyon. 1B data was obtained from
 California's Department of water resources website for the snow
 logger nearest these sites.FIG 1 data Dahlhoff et al.
 FE.xlsxFIG 2. Beetle abundance
 by elevationExcel file with 2 tabs.
 First tab is maximal abundance by site in 2012. Second tab shows
 statistical output of final analysis.FIG 2
 data.xlsxFIG 3. Abundance over
 time during droughtExcel file. Tab 1- raw
 data. Tabs 2 and 3 for conversion to analysis by Permanova. Tab 4
 permanova output.FIG 3
 data.xlsxFIG 4. Fecundity by
 elevationExcel file. Tab 1 is
 final data used in figure. Tab 2 is Jmp output. tab 3 is models used to
 ascertain importance of temperature. Tab 4 is complete raw data with
 behavior.FIG 4
 data.xlsxPhysiological and lab
 data reported in Figs 5 and 6These are raw data and
 Jmp outputs for CytOx data, development rate data, and MDH data reported
 in paper.Physiological and lab data (Fig
 5-6).xlsx