DOI: 10.5061/dryad.30893
title: Data from: Potential for adaptation to climate change: family-level variation in fitness-related traits and their responses to heat waves in a snail population

description: Background: On-going global climate change poses a serious threat for
 natural populations unless they are able to evolutionarily adapt to
 changing environmental conditions (e.g. increasing average temperatures,
 occurrence of extreme weather events). A prerequisite for evolutionary
 change is within-population heritable genetic variation in traits subject
 to selection. In relation to climate change, mainly phenological traits as
 well as heat and desiccation resistance have been examined for such
 variation. Therefore, it is important to investigate adaptive potential
 under climate change conditions across a broader range of traits. This is
 especially true for life-history traits and defences against natural
 enemies (e.g. parasites) since they influence organisms’ fitness both
 directly and through species interactions. We examined the adaptive
 potential of fitness-related traits and their responses to heat waves in a
 population of a freshwater snail, Lymnaea stagnalis. We estimated
 family-level variation and covariation in life history (size,
 reproduction) and constitutive immune defence traits [haemocyte
 concentration, phenoloxidase (PO)-like activity, antibacterial activity of
 haemolymph] in snails experimentally exposed to typical (15 °C) and heat
 wave (25 °C) temperatures. We also assessed variation in the reaction
 norms of these traits between the treatments. Results: We found that at
 the heat wave temperature, snails were larger and reproduced more, while
 their immune defence was reduced. Snails showed high family-level
 variation in all examined traits within both temperature treatments. The
 only negative genetic correlation (between reproduction and antibacterial
 activity) appeared at the high temperature. However, we found no
 family-level variation in the responses of most examined traits to the
 experimental heat wave (i.e. largely parallel reaction norms between the
 treatments). Only the reduction of PO-like activity when exposed to the
 high temperature showed family-level variation, suggesting that the cost
 of heat waves may be lower for some families and could evolve under
 selection. Conclusion: Our results suggest that there is genetic potential
 for adaptation within both thermal environments and that trait evolution
 may not be strongly affected by trade-offs between them. However, rare
 differences in thermal reaction norms across families indicate limited
 evolutionary potential in the responses of snails to changing temperatures
 during extreme weather events.
description: DataData is saved as a tab
 delimited text file (data.txt). Data file has the following columns: 1)
 temp - temperature treatment (15C, 25C); 2) fam - snail family (15
 families); 3) block - block of the experiment (6 blocks); 4) size - shell
 length (mm); 5) rep - reproduction during the experiment (0 = no, 1 =
 yes); 6) eggs - number of produced eggs; 7) haemo - haemocyte
 concentration of haemolymph (cells/ul); 8) A - antibacterial activity of
 haemolymph; 9) PO - PO-like activity of haemolymph.data.txt