Unscrambling variation in avian eggshell colour and patterning in a continent-wide study

The evolutionary drivers underlying marked variation in the pigmentation of eggs within many avian species remains unclear. The leading hypotheses proposed to explain such variation advocate the roles of genetic differences, signalling and/or structural integrity. One means of testing amongst these hypotheses is to capitalise on museum collections of eggs obtained throughout a broad geographic range of a species to ensure sufficient variation in predictors pertaining to each hypothesis. Here we measured colouration and patterning in eggs from 271 clutches of Australian Magpies (Cracticus tibicen) collected across most of their geographic range of ca. 7 million km2; encompassing eight subspecies, variation in environmental parameters, and the presence/ absence of a brood parasite. We found considerable variation in background colour, as well as in the extent and distribution of patterning across eggs. There was little evidence that this variation was explained by subspecies. However, we ...,
Correction Notice: An error in data manipulation was identified and corrected. A correction has been applied to this article (April 2024), approved by RSOS, and the data has been updated to reflect this correction. 

MagpieCode2024
Clean R Code for all Magpie analyses.
MagpieCombinedData2024
Clean and corrected colour dataset and maculation dataset.
OutlierDataset2024
Outlier dataset. 

 
, , # Data from: Unscrambling variation in avian eggshell colour and patterning in a continent-wide study

[https://doi.org/10.5061/dryad.q3b7b78](https://doi.org/10.5061/dryad.q3b7b78)

###### Correction Notice: An error in data manipulation was identified and corrected. A correction has been applied to this article (April 2024), approved by RSOS, and the data has been updated to reflect this correction. 

## Description of the data and file structure

**MagpieCode2024**

Clean R Code for all Magpie analyses (R).

**MagpieCombinedData2024**

Clean and corrected colour dataset and maculation dataset (csv).

**OutlierDataset2024**

Outlier dataset (csv).

 

## Sharing/Access information

Data was derived from the following sources:

* Distribution maps were extracted from the Directory of Australian Birds.
* Temperatures (Tmax, °C) and relative humidity (%) were downloaded from the Australian Water Availability Project via [http://www.bom.gov.au](http://www.bom.gov.au).
* Leaf area in...