Colourful urban birds: Urban-tolerant birds have more elaborate colours, more blue and less brown

Urbanization, one of the most extreme and rapidly-expanding human-induced landscape changes, imposes multiple challenges to wildlife. Studies in urban ecology have explored how urbanization affects organisms. However, still little is known about the relationship between urbanization and animal coloration, even though colours fulfil key functions such as camouflage, signalling, and thermoregulation. We use a global bird database on urban tolerance and combine it with quantitative colour estimates to test whether urban-tolerant species differ in colour from less urban-tolerant ones. Our interspecific comparative analyses revealed that urban-tolerant birds are more likely to have blue, dark grey and black colours and less likely to have brown or yellow colours. However, after statistically accounting for phylogenetic relatedness, only the effects of blue and brown colours remained significant. Overall, urban-tolerant species have more elaborated colours, but we found no association between..., , , # Global dataset of bird coloration and traits

[https://doi.org/10.5061/dryad.jq2bvq8jg](https://doi.org/10.5061/dryad.jq2bvq8jg)

This dataset contains variables separated in two different Excel sheets: species level and assemblage level with the readme containing the information of the different variables in each file.

## Description of the data and file structure

**Variables and Description**

phylo.name: scientific name matching taxonomy of www.birdtree.org

urban.slope: urban success index: slope of regression, log(Abundance+0.1)~urbanization level

urban.diff.maxmin: urban success index: log(Abundance at maximum level of urbanization +0.1) - log(Abundance at minimum level of urbanization +0.1) [Note that in this case the maximum or minimum levels of urbanization are not always 5 and 1 respectively]

urban.diff.12vs345: urban success index : mean(log(Abundance at level of urbanization 5 +0.1), log(Abundance at level of urbanization 4 +0.1), log(Abundance at level of urbanizatio...