Nests are essential constructions that directly determine fitness, yet their structure can vary substantially across bird species. While there is evidence supporting a link between nest architecture and the habitat a species occupies, we still ignore what ecological and evolutionary processes are linked to different nest types. Using information on 3175 species of songbirds, we show that – after controlling for latitude and body size – species that build domed nests (i.e., nests with a roof) have smaller ranges, are less likely to colonise urban environments and have potentially higher extinction rates compared to species with open and cavity nests. Domed nests could be a costly specialisation, and we show these nests take more time to be built, which could restrict breeding opportunities. These diverse strands of evidence suggest that transition from domed to open nests in passerines could represent an important evolutionary innovation behind the success of the largest bird radiation.

The dataset presented was collated from various online resouces and comprises data on nest information and other variables for 3175 species of passerine birds. This data has been cleaned and is the ones employed in all analyses. We also attach code and files that are needed to reproduce analyses and main graphs.

Description of files:

Nests_Dryad_Jan2022.rmd: R Markdown file containing all PGLS regressions and code for main figures in the text. 

env_nest_size_total_2022.csv: Dataset with all information needed to run the analyses in PGLS models

function_pgls_dryad.R: Function needed for code above, runs a PGLS

mcc_tree10.rds: MCC tree used for main analyses, obtained from distribution of 10000 from birdtree.org

nest_building.csv: Data file with information for nest building analysis, 277 species

Model_nest_building_reduced.rds: Model results used for graph of nest building

MCC_Range_nest.logsize.lat.cont.q2.oct.cat2.R: Model results used for predictions in Figure on range size

Model_nest_building100_2021.rds: Model results for 100 trees from building analysis

Additional dataset: File with information on additional comments and sources of nest information