Evolutionary mismatch along salinity gradients in a Neotropical water strider
Data files
Feb 28, 2022 version files 54.22 KB
-
Castill&DeLeon_fitness_data.csv
-
Castill&DeLeon_LC50_data.csv
-
Castill&DeLeon_survival_by_sex.csv
Abstract
The evolution of local adaptation is crucial for the in situ persistence of populations in changing environments. However, selection along broad environmental gradients could render local adaptation difficult, and might even result in maladaptation. We address this issue by quantifying fitness trade-offs (via common garden experiments) along a salinity gradient in two populations of the Neotropical water strider Telmatometra withei – a species found in both fresh (FW) and brackish (BW) water environments across Panama. We found evidence for local adaptation in the FW population in its home FW environment. However, the BW population showed only partial adaptation to the BW environment, with a high magnitude of maladaptation, along naturally-occurring salinity gradients. Indeed, its overall fitness was ~ 60% lower than that of the ancestral FW population in its home environment, highlighting the role of phenotypic plasticity, rather than local adaptation, in high salinity environments. This suggests that populations seemingly persisting in high salinity environments might in fact be maladapted, following drastic changes in salinity. Thus, variable selection imposed by salinization could result in evolutionary mismatch, where the fitness of a population is displaced from its optimal environment. Understanding the fitness consequences of persisting in fluctuating salinity environments is crucial to predict the persistence of populations facing increasing salinization. It will also help develop evolutionarily informed management strategies in the context of global change.
Methods
This dataset corresponds to experimental estimates of salinity tolerance based on LC50 (the salinity concentration at which 50% of the sampled population exhibit mortality) in both fresh and brackish water populations of the Neotropical water strider Telmatometra withei in Panama. It also contains estimates (based common garden experiments) of variation in four fitness correlated traits (survival, fecundity, oviposition and number of immatures) along a salinity gradient in populations of T. withei. It also contains data on survival by sex in T. withei from both fresh and brackish water populations.
Usage notes
There are no missing values, and column names are self-explanatory.