Data from: Many-to-one form-to-function mapping weakens parallel morphological evolution
Thompson, Cole J., The University of Texas at Austin
Ahmed, Newaz, The University of Texas at Austin
Veen, Thor, The University of Texas at Austin
Peichel, Catherine Lynn, University of Bern
Hendry, Andrew P., McGill University
Bolnick, Daniel I., The University of Texas at Austin
Stuart, Yoel E., The University of Texas at Austin
Published Aug 18, 2017 on Dryad.
Cite this dataset
Thompson, Cole J. et al. (2017). Data from: Many-to-one form-to-function mapping weakens parallel morphological evolution [Dataset]. Dryad. https://doi.org/10.5061/dryad.5b1k0
Evolutionary ecologists aim to explain and predict evolutionary change under different selective regimes. Theory suggests that such evolutionary prediction should be more difficult for biomechanical systems in which different trait combinations generate the same functional output: “many-to-one mapping”. Many-to-one mapping of phenotype to function enables multiple morphological solutions to meet the same adaptive challenges. Therefore, many-to-one mapping should undermine parallel morphological evolution, and hence evolutionary predictability, even when selection pressures are shared among populations. Studying 16 replicate pairs of lake- and stream-adapted threespine stickleback (Gasterosteus aculeatus), we quantified three parts of the teleost feeding apparatus and used biomechanical models to calculate their expected functional outputs. The three feeding structures differed in their form-to-function relationship from one-to-one (lower jaw lever ratio) to increasingly many-to-one (buccal suction index, opercular 4-bar linkage). We tested for (1) weaker linear correlations between phenotype and calculated function, and (2) less parallel evolution across lake-stream pairs, in the many-to-one systems relative to the one-to-one system. We confirm both predictions, thus supporting the theoretical expectation that increasing many-to-one mapping undermines parallel evolution. Therefore, sole consideration of morphological variation within and among populations might not serve as a proxy for functional variation when multiple adaptive trait combinations exist.
Main R script to run first, to load packages, and set up directory structure, along with other housekeeping.
Contains functions for analysis. Is sourced by main.cole
Contains figure functions. Is sourced by main.R
analysis code, used to generate the statistics, analyses, and output in the manuscript. requires main.cole to be run first.
Calculates Kinematic Transmission for the Opercular 4-bar system.
Code for the simulation that compares levels of many-to-one mapping across biomechanical systems.
Gut content data.
Biomechanical trait measurements.
National Science Foundation, Award: DEB-1144773 and DEB-1144556