DOI: 10.5061/dryad.qfttdz0mw
title: Plasticity and associated epigenetic mechanisms play a role in thermal evolution during range expansion

description: Due to global change many species are shifting their distribution and are
 thereby confronted with novel thermal conditions at the moving range
 edges. Especially during the initial phases of exposure to a new
 environment, it has been hypothesized that plasticity and associated
 epigenetic mechanisms enable species to cope with environmental change. We
 tested this idea by capitalizing on the well-documented southward range
 expansion of the damselfly Ischnura elegans from France into Spain where
 the species has invaded warmer regions in the 1950s in eastern Spain (old
 edge region) and in the 2010s in central Spain (new edge region). Using a
 common garden experiment at rearing temperatures matching the ancestral
 and invaded thermal regimes, we tested for evolutionary changes in
 (thermal plasticity in) larval life history and heat tolerance in these
 expansion zones. Through the use of de- and hypermethylating agents we
 tested whether epigenetic mechanisms play a role in enabling heat
 tolerance during expansion. We used the phenotype of the native sister
 species in Spain, I. graellsii, as proxy for the locally adapted
 phenotype. New edge populations converged towards the phenotype of the
 native species through plastic thermal responses in life history and heat
 tolerance while old edge populations (partly) constitutively evolved a
 faster life history and higher heat tolerance than the core populations,
 thereby matching the native species. Only the heat tolerance of new edge
 populations increased significantly when exposed to the hypermethylating
 agent. This suggests that the DNA methylation machinery is more amenable
 to perturbation at the new edge and shows it is able to play a role in
 achieving a higher heat tolerance. Our results show that both (evolved)
 plasticity as well as associated epigenetic mechanisms are initially
 important when facing new thermal regimes but that their importance
 diminishes with time.
description: Methods are fully described in the associated manuscript.
description: # Dataset associated with manuscript "Plasticity and associated
 epigenetic mechanisms play a role in thermal evolution during range
 expansion" --- Due to global change many species are shifting their
 distribution and are thereby confronted with novel thermal conditions at
 the moving range edges. Especially during the initial phases of exposure
 to a new environment, it has been hypothesized that plasticity and
 associated epigenetic mechanisms enable species to cope with environmental
 change. We tested this idea by capitalizing on the well-documented
 southward range expansion of the damselfly Ischnura elegans from France
 into Spain where the species has invaded warmer regions in the 1950s in
 eastern Spain (old edge region) and in the 2010s in central Spain (new
 edge region). Using a common garden experiment at rearing temperatures
 matching the ancestral and invaded thermal regimes, we tested for
 evolutionary changes in (thermal plasticity in) larval life history and
 heat tolerance in these expansion zones. Through the use of de- and
 hypermethylating agents we tested whether epigenetic mechanisms play a
 role in enabling heat tolerance during expansion. We used the phenotype of
 the native sister species in Spain, I. graellsii, as proxy for the locally
 adapted phenotype. New edge populations converged towards the phenotype of
 the native species through plastic thermal responses in life history and
 heat tolerance while old edge populations (partly) constitutively evolved
 a faster life history and higher heat tolerance than the core populations,
 thereby matching the native species. Only the heat tolerance of new edge
 populations increased significantly when exposed to the hypermethylating
 agent. This suggests that the DNA methylation machinery is more amenable
 to perturbation at the new edge and shows it is able to play a role in
 achieving a higher heat tolerance. Our results show that both (evolved)
 plasticity as well as associated epigenetic mechanisms are initially
 important when facing new thermal regimes but that their importance
 diminishes with time. ## Description of the Data and file structure These
 datasets were used to assess the effect of temperature on life history and
 heat tolerance: **dataset_temperature_life_history.xlsx** * ID: ID of the
 larva * temp: temperature at which the larva was reared (°Celsius) * pop:
 population origin of the larva * region: region origin of the larva *
 mother: ID of the mother of the larva * PopMother: combination of
 population and mother * date_f0: day the larva reached the last larval
 stage (F0) * sex: sex of the larva (m: male; f: female; NA: not available)
 * mass_day2: mass in mg of the larva one day after reaching F0 *
 mass_day8: mass in mg of the larva 7 days after reaching F0 *
 seperation_date: data at which the individual was seperated into an
 individual cup * development_time: days untill reaching F0
 **dataset_temperature_heat_tolerance.xlsx** * ID: ID of the larva * temp:
 temperature at which the larva was reared (°Celsius) * pop: population
 origin of the larva * region: region origin of the larva * mother: ID of
 the mother of the larva * PopMother: combination of population and mother
 * date_f0: day the larva reached the last larval stage (F0) * sex: sex of
 the larva (m: male; f: female; NA: not available) * treatment: the
 treatment allocation of the larva one day after reaching F0 (control:
 control conditions; zeb: zebularine treatment; 3-ab: 3-aminobenzamide
 treatment) * mass_day2: mass in mg of the larva one day after reaching F0
 * mass_day8: mass in mg of the larva 7 days after reaching F0 * CTmax: the
 temperature at which the larva become immobile during the CTmax experiment
 (°Celsius) * Grid: the grid in which the larva was present during the
 CTmax experiment * Machine_set: the machine set used for this larva during
 the CTmax experiment (three identical thermocyclers were used: A; B; C)
 ### These datasets were used to assess the effect of the drug treatment on
 heat tolerance and global DNA methylation levels:
 **dataset_drug_treatment_heat_tolerance.xlsx** * ID: ID of the larva *
 temp: temperature at which the larva was reared (°Celsius) * pop:
 population origin of the larva * region: region origin of the larva *
 mother: ID of the mother of the larva * PopMother: combination of
 population and mother * date_f0: day the larva reached the last larval
 stage (F0) * sex: sex of the larva (m: male; f: female; NA: not available)
 * treatment: the treatment allocation of the larva one day after reaching
 F0 (control: control conditions; zeb: zebularine treatment; 3-ab:
 3-aminobenzamide treatment) * mass_day2: mass in mg of the larva one day
 after reaching F0 * mass_day8: mass in mg of the larva 7 days after
 reaching F0 * CTmax: the temperature at which the larva become immobile
 during the CTmax experiment (°Celsius) * Grid: the grid in which the larva
 was present during the CTmax experiment * Machine_set: the machine set
 used for this larva during the CTmax experiment (three identical
 thermocyclers were used: A; B; C)
 **dataset_drug_treatment_DNA_methylation_levels.xlsx** *
 5MedCyd_concentration: Log10 of the 5MedCyd concentration in ul that was
 used as a proxy for the global methylation level of the larva * pop:
 population origin of the larva * mother: ID of the mother of the larva *
 region: region origin of the larva * treatment: the treatment allocation
 of the larva one day after reaching F0 (control: control conditions; zeb:
 zebularine treatment; 3-ab: 3-aminobenzamide treatment) * sex: sex of the
 larva (m: male; f: female; NA: not available) * CTmax: the temperature at
 which the larva become immobile during the CTmax experiment (°Celsius) *
 extraction_method: DNA extraction method that was used to extract DNA
 (dna_kit: Qiagen's DNA extraction kit; dnarna_kit: Qiagen's
 DNA/RNA extraction kit). This DNA was afterwards used in the ELISA
 analysis ## Sharing/access Information Links to other publicly accessible
 locations of the data: none Was data derived from another source? no