The Guillemot is a seabird that lays its eggs on a bare rock ledge on a cliff face.

The Guillemot is a seabird that lays its eggs on a bare rock ledge on a cliff face. When an egg is accidentally dislodged, its shape causes it to spin in a tight circle, which prevents it from falling off the ledge into the sea. Unique nano-structures on guillemot eggshells eggs enable them to survive precarious habitats, on exposed cliffs with no nest.

Researchers performed engineering tests on the eggshells and found that those of the guillemot have several unique proprieties due to these nano -structures: higher water contact angle (which means they were more hydrophobic), rougher surface (which helps prevent the egg from falling off the cliff or the parents feet) and higher rate of gaseous exchange (which helps them cope with the high salt content from the sea spray).

Source and further reading:
http://www.sciencedaily.com/releases/2013/07/130705101828.htm
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