The evolution of colorful eggs

[Halichoeres]

Bird eggs show a surprising variety of pigments (if you've ever seen the eggs of an American robin, you'll know what I'm talking about). This study used spectroscopy (quantitative color analysis based on absorbance/reflectance properties of different pigment residues) to find out how widespread colorful eggs might be. The upshot: ornithischian and sauropod eggs were probably boring, but basically all eumaniraptoran clades have at least some members with colorful eggs. Hence, this feature evolved long before the true birds. The world of dinosaurs was vibrant!



Paper (open access): https://www.nature.com/articles/s41586-018-0646-5