https://doi.org/10.5061/dryad.rfj6q57ht

We tested a widespread species of Livebearing fish from the Dominican Republic, Limia perugiae for male preferences for larger female body size. We found that males indeed prefer larger females. However, there were no differences between the populations we used, although the populations differed in environmental variables, such as salinity.

Description of the data and file structure

Our data is raw data reporting typical data from binary choice tests. There are four data sheets in the Excel file. The first column of sheet 1, “Experiment” provides a unique identifier for each male used. The second column “Fish” provides the order in which males were tested. The file is sorted by population, consequently the order seems random. The third column refers to the population of males used. See main text and sheet 2 for population info, but note that alb refers to the Gold variant, gh46 to Balneario La Zurza, and coco to Los Cocos. The next column, “SVL” gives the standard length of the fish in mm. Standard length is measured as the distance from the snout to the end of the spinal column. The column “Date” provides the day of the test. The column “Trial #1 (TSOL)” refers to the time in seconds spent on the left side of the choice tank during the first half of the choice test. The three columns to the right give times in seconds for the time on the right side during trial one and – after switching the stimuli – the same information for the second trial. The next two columns show the combined times as total times spent with the larger and the smaller female. The column “Small female (mm)” gives the standard length of the smaller female, and the next gives the standard length of the larger female. The final two columns identify trials that showed side biases (see main text for discussion) and miscellaneous notes.

The second sheet, “Clean Data” provides the same data as sheet 1 but amended with populations classified as either having salinity or not (Column 2, “Salinity”. The Column “Size” refers to the relative size of the male in the size distribution of the population (see main text for context). Furthermore, the column “SOP” reports the strength of the male preference as a corrected percentage with 0 meaning that the male spent all his time with the smaller female.

Sheet 3 contains sex and size information for all fishes used in the study. See sheet 1 for column description.

Sheet 4 provides summary data for the whole study, organized by population.

Finally, sheet 5 (“Coordinates”) contains the coordinates for the sampled populations.