DOI: 10.5061/dryad.k3836
title: Data from: Differences in rheotactic responses contribute to divergent habitat use between parapatric lake and stream threespine stickleback

description: Migration among populations is widely thought to undermine adaptive
 divergence, assuming gene flow arises from random movement of individuals.
 If individuals instead differ in dispersal behavior, phenotype-dependent
 dispersal can reduce the effective rate of gene flow or even facilitae
 divergence. For example, parapatric populations of lake and stream
 stickleback tend to actively avoid dispersing into the adjoining habitat..
 However, the behavioral basis of this non-random dispersal was previously
 unknown. Here we show that lake and stream stickleback exhibit divergent
 rheotactic responses (behavioral response to currents). During the
 breeding season, wild-caught inlet stream stickleback were better than
 lake fish at maintaining position in currents, faced upstream more, and
 spent more time in low-current areas. As a result, stream fish expended
 significantly less energy in currents than did lake fish. These divergent
 rheotactic responses likely contribute to divergent habitat use by lake
 and stream stickleback. Although rheotactic differences were absent in
 non-breeding fish, divergent behavior of breeding-season fish may suffice
 for assortative mating by breeding location. The resulting reproductive
 isolation between lake and stream fish may explain the fine-scale
 evolutionary differentiation in parapatric stickleback populations.
description: Jiang_Data.csvMetadata for Jiang et al 2015 Evolution. The file Jiang_Data.csv contains all data required to recreate analyses for Jiang, Torrance, Peichel, and Bolnick 2015, Differences in Rheotactic Responses Contribute to Divergent Habitat Use Between Parapatric Lake and Stream Threespine Stickleback. Evolution. The data columns are as follows: Group: source population, Fish_ID: a unique identifier, Flow_Direction: The direction that the water pump power heads pointed to generate flow, whether or not flow was actually initiated by plugging in the power heads. That is, we assign a flow direction randomly whether or not we turned on the pumps to actually generate flow. First_trial: whether a given fish (see Fish_ID) was tested first in still or flowing water. Randomly assigned. Current: Flow presence/absence (Flow/still) for the particular trial in the data row. Group: Whether the fish was wild-caught (Field), or Lab-raised. Subgroup: Whether the fish came from near or in the inlet stream, or outlet stream. Origin: Whether the fish came from the lake or stream. Location: A categorical summary of where the fish spent most of its time in the flow tank. Distance.total: Net upstream movement. Distance.up.total: Cumulative upstream movement. Per.upstream: Percentage of time spent facing upstream. Location: Score representing the relative use of inner,middle, and outer concentric areas of the flow tank. The numbers presented here are obtained by digitizing videos of each fish (2 videos per fish, flow and still water), and converting the videos into data tables (one per fish) representing the fish’s location and orientation in ~1 second time intervals. These very large tables are available from the authors upon request: email danbolnick@austin.utexas.edu.