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Speckled Dinosaur Eggs?

Interesting tidbit, and by extension...


Birds' eggs are unique in their diverse pigmentation. This diversity is
greatest amongst perching birds (order Passeriformes: 60% of all bird
species), which include many familiar species including tits and warblers.
Despite intense interest, the purpose, in most species, of these patterns
was unknown.

Most passerines lay eggs speckled with reddish protoporphyrin spots
forming a ring around the egg's blunt end, on an otherwise unpigmented
shell. Evidence in a paper by Gosler, Higham & Reynolds soon to appear in
Ecology Letters now suggests that rather than giving a visual signal,
protoporphyrins strengthen the eggshell by compensating for reduced
eggshell-thickness caused by calcium deficiency.

Pigment spots on great tit eggs specifically marked thinner areas of
shell, with darker spots marking yet thinner shell than paler spots, and
females nesting on low-calcium soils, laid thinner-shelled, more-spotted
eggs than those on high-calcium soils nearby. Pigmentation may offer a way
to assess eggshell quality.