A fossilized nest, found in Spain and containing five eggs, belonged to a previously unknown species of palaeoflamingo, the ancient ancestor of the modern, long-legged bird. The nest — made from twigs and leaves 15 million to 20 million years ago — was found alongside bone fragments, encased in limestone in the Bardenas Reales de Navarra Natural Park.
Gerald Grellet-Tinner from the Field Museum in Chicago, Illinois, and his team report that the eggshells are characteristic of flamingos, whereas the nest and the number of eggs more closely resemble those of grebes, freshwater diving birds. Modern grebes and flamingos differ in their nest-building and feeding styles, but DNA studies have suggested that the two species are closely related. The present discovery supports that connection and points to a time when the two species shared survival strategies.