Researchers ponder the shape of birds' eggs

Researchers ponder the shape of birds' eggs
A guillemot egg showing the typically pointed shape. Credit: TR Birkhead

The shape of birds' eggs varies considerably, for reasons that are unclear.

The peculiarly elongated and pointed shape of the Common Guillemot's egg is thought to prevent it from rolling off the narrow cliff ledge it is laid on, but new research suggests instead that the has more to do with providing resistance against impacts and protection from faecal and other contamination.

"I have studied guillemots for over forty years and have never been convinced by the rolling explanation. It has been exciting coming up with and testing them," said Dr. Tim Birkhead, lead author of the Ibis study.

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More information: Ibis, DOI: 10.1111/ibi.12458
Provided by Wiley
Citation: Researchers ponder the shape of birds' eggs (2017, February 23) retrieved 20 July 2019 from
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Mar 03, 2017
I don't even know how those little birds manage to relax their egg holes enough to even lay an egg that big. They don't seem to suffer from it. I did watch a chicken lay an egg and it just seemed to appear from nowhere. The chicken had extended its lower feathers around the whole bottom area.

I don't know much about various bird anatomies, but I would have thought that the anatomy would come first, in terms of shaping the egg. Just goes to show. This egg is an especially sturdy shape and easy to wash they say.

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