Using 3D printed eggs to examine the egg-rejection behaviour of wild birds

Loading...
Thumbnail Image

Authors

Igic, Branislav
Nunez, Valerie
Voss, Henning U.
Croston, Rebecca
Aidala, Zachary
Lopez, Analia V.
Van Tatenhove, Aimee
Holford, Mandë E.
Shawkey, Matthew D.
Hauber, Mark E.

Issue Date

2015

Type

Article

Language

Keywords

Artificial egg , Turdus migratorius , Brood parasitism , 3D printing , Egg rejection , American robin , Cowbird , Experimental techniques , Molothrus ater

Research Projects

Organizational Units

Journal Issue

Alternative Title

Abstract

The coevolutionary relationships between brood parasites and their hosts are often studied by examining the egg rejection behaviour of host species using artificial eggs. However, the traditional methods for producing artificial eggs out of plasticine, plastic, wood, or plaster-of-Paris are laborious, imprecise, and prone to human error. As an alternative, 3D printing may reduce human error, enable more precise manipulation of egg size and shape, and provide a more accurate and replicable protocol for generating artificial stimuli than traditional methods. However, the usefulness of 3D printing technology for egg rejection research remains to be tested. Here, we applied 3D printing technology to the extensively studied egg rejection behaviour of American robins, Turdus migratorius. Eggs of the robin's brood parasites, brown-headed cowbirds, Molothrus ater, vary greatly in size and shape, but it is unknown whether host egg rejection decisions differ across this gradient of natural variation. We printed artificial eggs that encompass the natural range of shapes and sizes of cowbird eggs, painted themto resemble either robin or cowbird egg colour, and used them to artificially parasitize nests of breeding wild robins. In line with previous studies, we show that robins accept mimetically coloured and reject non-mimetically coloured artificial eggs. Although we found no evidence that subtle differences in parasitic egg size or shape affect robins' rejection decisions, 3D printing will provide an opportunity for more extensive experimentation on the potential biological or evolutionary significance of size and shape variation of foreign eggs in rejection decisions. We provide a detailed protocol for generating 3D printed eggs using either personal 3D printers or commercial printing services, and highlight additional potential future applications for this technology in the study of egg rejection.

Description

Citation

Igic, B., Nunez, V., Voss, H. U., Croston, R., Aidala, Z., López, A. V., … Hauber, M. E. (2015). Using 3D printed eggs to examine the egg-rejection behaviour of wild birds. PeerJ, 3, e965. doi:10.7717/peerj.965

Publisher

License

Creative Commons Attribution 4.0 International

Journal

Volume

Issue

PubMed ID

ISSN

2167-8359

EISSN

Collections