Ecological, genetic and geographical divergence explain differences in sunbird (Nectariniidae) colouration
Data files
May 08, 2024 version files 8.26 MB
Abstract
Bird plumages are among the most elaborate ornaments, displaying almost all colours of the rainbow. Why and how birds are so colourful remains an open question with multiple and sometimes competing hypotheses. Different colours in different patches might have different functions and thus result from different forms of selection (e.g., natural vs. sexual selection). Here we test three hypotheses that might explain colour differences: (1) species isolation, (2) light environment, and (3) Brownian motion. We show that both natural and sexual selection affect the evolution of sunbird colouration, but that their extent and direction differs between sexes, by species interactions, and for different patches across the body. Even though overlap in the light environment explains part of colour differences in species, no colour metric (brightness and chroma) correlates to the light environment. It is likely that these results, where multiple forms of selection influence colouration in different ways, are more general across birds, highlighting the need to investigate bird colouration as a network of individual but inter-connected colour patches.
README: Ecological, genetic and geographical divergence explain differences in sunbird (Nectariniidae) colouration
This dataset comprises the following files:
- An R file called coldist_vs_sympatry_final.R calculates how colour divergences relate to allopatry/sympatry, ecological overlap and genetic distances.
- This file requires an:
- input tree (beautifile_v3_uncorrelated_MCC) (see below)
- input file distances3 which contains species names (sp1/2), the degree of overlap, whether or not they are sympatric and then colour distances for CR, MA, TH, BA, BD, and BE (all in JND units), as well as genetic distances (in my), NDVI (Normalized Difference Vegetation Index) overlap and minimal distances between distributions (in km).
- This file requires an:
- Two R files called habitat_type, which look at the relationship between colour metrics and NDVI and this for female (dataset called habitat_type_F2) and male colours (dataset called habitat_type2).
- This file requires an:
- input tree (beautifile_v3_uncorrelated_MCC) -- see https://doi.org/10.5061/dryad.7h44j0zxp
- input colour data sunbirds_ave.csv (see below)
- input habitat data habitat_2 (see below)
- This file requires an:
- Phylogenetic tree of sunbirds (beautifile_v3_uncorrelated_MCC).
- A file (distances.txt) containing geographic distances (km), colour distances (JND), NDVI overlap, genetic distances (mya) and geographic overlap between species pairs.
- A file (habitat_2.csv) with average NDVI values per species.
- A file (sunbrids_ave.csv) with raw colour measurements.
- Several output files that were created by the code (coldist_vs_sympatry.txt, NDVI_col_x_M/F.txt). These are added to easily compare results.
In all files, NAs/? correspond to missing data. In all files CR, MA, TH, BA, BD, and BE stand for Crown, Mantle, Throat, Breast 1, Breast 2 and Belly.