The files invasionexperiment1.csv and invasionexperiment2.csv contain the data from our first and second invasion experiment, respectively. Entries are separated by commata. Explanation of column headings: day: day since the introduction of D. lumholtzi unit: number of experimental container number_native: number of native Daphnia counted in the sample number_lumholtzi: number of Daphnia lumholtzi counted in the sample (The number on day 0 is obtained by multiplying the introduced 25 individuals with the fraction counted.) fraction_counted: fraction of the total volume in the container (25L in the first experiment, 10 in the second experiment) that was sampled (Thus, to obtain the volume of the sample multiply the fraction_counted with 25 or 10, respectively.) temperature: in °C predation: whether or not a planktivorous fish (bitterling) was allowed to prey on the Daphnia (see manuscript for detailed description of predation regime) clone: introduced D. lumholtzi clone, TE = inducibly defended Texas clone, AZ = permanently defended Arizona clone The file longtermexperiment.csv contains the data from the long term experiment (TE clone introduced in the absence of predation). Entries are separated by commata. Explanation of column headings: day: day since the introduction of D. lumholtzi density.native: density of native Daphnia in individuals per L density.lumholtzi: density of Daphnia lumholtzi in individuals per L temperature: in °C density.total: total Daphnia density in individuals per L Should you have any questions, please contact Meike Wittmann (wittmann@bio.lmu.de).