DOI: 10.5061/dryad.5x69p8db7
title: An experimental test of the evolutionary consequences of sympatry in Drosophila subquinaria

description: Prezygotic isolation is often stronger between sympatric as opposed to
 allopatric taxa, but the underlying cause can be difficult to infer from
 comparative studies alone. Experimental evolution, where evolutionary
 responses to treatments manipulating the presence/absence of
 heterospecific individuals are tracked, can provide a powerful
 complementary approach. We used experimental evolution to investigate a
 naturally occurring pattern of reproductive character displacement in the
 mushroom-feeding fly, Drosophila subquinaria. In nature, female D.
 subquinaria from populations sympatric with the closely related D. recens
 discriminate more strongly against heterospecific males than do females
 from allopatric populations. Starting with 16 replicate allopatric
 populations of D. subquinaria, we manipulated the presence/absence of D.
 recens during mating (experimental sympatry vs. control) and, when
 present, we allowed hybrids to live or killed them each generation. Across
 12 generations, heterospecific offspring production from no-choice mating
 trials between D. subquinaria females and D. recens males declined in both
 experimental sympatry treatments relative to the control, suggesting
 increased sexual isolation. Male cuticular hydrocarbon profiles also
 evolved, but only in the hybrids killed treatment. Our results strongly
 imply that the existing reproductive character displacement in wild D.
 subquinaria populations was an evolutionary response to selection arising
 from secondary contact with D. recens.
description: # An experimental test of the evolutionary consequences of sympatry in
 Drosophila subquinaria \[Access this dataset on Dryad]
 Uploaded data for a
 multi-generation evolution experiment testing the effect of artificial
 sympatry between two drosophila species. Data includes measures of mating
 rates and CHCs (cuticular hydrocarbons, a kind of contact pheromone) at
 each generation in each population. ## Description of the data and file
 structure data_cons.csv &lt;- contains conspecific mating rates from
 no-choice mating trials conducted in each population at each sampling
 generation (0,6, and 12). Columns are as follows: generation (sampling
 generation), block (experimental block where populations were placed in
 block 1 or block 2), blockXgen (factor for statistical methods
 concatonating block and generation), treatment (experimental treatment;
 Allo treatment = control, Str reinforcement = Hybrids killed, Wk
 reinforcement = Hybrids live), popID (population ID), male mated with
 (indicating conspecific or heterospecific mating rate, N mated (number of
 successful matings), N not mated (number of failed matings), N total
 trials (total number of matings), fraction mated (mating rate).
 data_hetero.csv &lt;- contains heterospecific mating rates from no-choice
 mating trials conducted in each population at each sampling generation
 (0,6, and 12). Columns are as follows: generation (sampling generation),
 block (experimental block where populations were placed in block 1 or
 block 2), blockXgen (factor for statistical methods concatonating block
 and generation), treatment (experimental treatment; Allo treatment =
 control, Str reinforcement = Hybrids killed, Wk reinforcement = Hybrids
 live), popID (population ID), male mated with (indicating conspecific or
 heterospecific mating rate, N mated (number of successful matings), N not
 mated (number of failed matings), N total trials (total number of
 matings), fraction mated (mating rate). dm.csv &lt;- contains male CHC
 data from each sampling generation. Columns are as follows: sampleID (CHC
 sample ID), block (experimental block where populations were placed in
 block 1 or block 2), population (label for population number within a
 treatment and block), popID (population ID), Popgen (factor for
 statistical methods concatonating population and generation), blockXgen
 (factor for statistical methods concatonating block and generation),
 treatment (experimental treatment; Allo treatment = control, Str
 reinforcement = Hybrids killed, Wk reinforcement = Hybrids live),
 generation (sampling generation), sex (male or female), clr1:clr24
 (centered log ratio transformed relative CHC concentrations, numbers
 indicate compound numbers from Curtis 2013, see methods for details)
 df.csv &lt;- contains female CHC data from each sampling generation.
 Columns are as follows: sampleID (CHC sample ID), block (experimental
 block where populations were placed in block 1 or block 2), population
 (label for population number within a treatment and block), popID
 (population ID), Popgen (factor for statistical methods concatonating
 population and generation), blockXgen (factor for statistical methods
 concatonating block and generation), treatment (experimental treatment;
 Allo treatment = control, Str reinforcement = Hybrids killed, Wk
 reinforcement = Hybrids live), generation (sampling generation), sex (male
 or female), clr2:clr20 (centered log ratio transformed relative CHC
 concentrations, numbers indicate compound numbers from Curtis 2013, see
 methods for details) Additional data used can be found in Dyer et al. 2014
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