Urban environments promote adaptation to multiple stressors

Anthropogenic activities have drastically changed environmental conditions worldwide, negatively impacting biodiversity and ecosystem services. At the same time, the majority of the human population lives in urban areas that are greatly altered from natural habitats. Nevertheless, many species thrive in urban environments. To improve our knowledge of evolution and adaptation in these anthropogenically impacted habitats, we conducted the widest series of stress experiments to date with three marine taxa: one mussel and two gammarid species. We compared intraspecific populations from protected and human-altered habitats to determine their tolerance to salinity, temperature and partial pressure of CO2 in water (pCO2) regimes. Populations from impacted habitats typically outperformed protected habitat populations, with individuals from the most impacted habitat being the most robust. We propose that urban populations are adapting to life in disturbed environments — this adaptation concurren..., Populations of one mussel (i.e., Mytilus sp.) and two gammarid species (i.e., Gammarus locusta and G. salinus) were collected in protected and human-altered habitats (i.e., impacted) in the Baltic Sea in Germany. The protected habitat was Schleimünde (Maasholm), while the human-altered habitat was the Kiel fjord, with three locations: i) downtown Kiel; ii) Kiel canal; and iii) Falckenstein beach. Species were collected from May 2016 until January 2021, depending on when a particular species/population experiment was conducted as well as sampling logistics. Two different types of experiments were conducted for each population of each species, with two crossed stressors: i) temperature – pCO2 experiments; and ii) temperature – salinity experiments. In both types of these multiple-stressor experiments with factorial stressor arrangements, following the acclimatization period to laboratory environment, the stress tests were conducted using ten mean-size adult individuals per replicate; exce..., , # Urban environments promote adaptation to multiple stressors

[https://doi.org/10.5061/dryad.3tx95x6qx](https://doi.org/10.5061/dryad.3tx95x6qx)

## Description of the data and file structure

There are two files: the first one containing data of the temperature – pCO2 experiments, and the second one containing data of the temperature – salinity experiments. The files contain information for the ambient and treatment experiments by providing data on survival of tested individuals in manipulated temperature, pCO2 and/or salinity conditions. Records of temperature, pCO2 and/or salinity are included as well.

### Files and variables

#### File: Temperature\_-\_pCO2.xlsx

**Description:** Each excel sheet (i.e., Mytilus sp. Schleimünde, Mytilus Kiel Fjord, G. locusta Schleimünde, G. locusta Falckenstein, G. salinus Schleimünde, G. salinus Kiel Kanal, and G. salinus Kiel Fjord) represents one experiment for one population of Mytilus sp., Gammarus locusta and Gammarus salinus, respectively. ...