Eggs evolved color and speckles only once — during the age of dinosaurs
Analysis of pigmentation in the eggs of modern birds and nonavian dinosaurs suggests similarities
The colorful, speckled eggs of modern birds are an innovation inherited from their nonavian dinosaur ancestors.
A new analysis of the pigmentation in modern and fossilized eggshells suggests that eggs evolved to be colorful only once — in modern birds’ dinosaur ancestors, a team of vertebrate paleontologists report online October 31 in Nature. Color patterns found in the eggshells of theropod dinosaurs, a lineage that includes Tyrannosaurus rex and smaller winged dinosaurs such as Microraptor, were very similar to those of modern birds, says Jasmina Wiemann of Yale University.