This research “provides good evidence that this can also be a very important part of the communication between parents and their offspring.” “Cosmetic coloration in birds mostly has been studied and understood or interpreted as serving as a signaling function, a sexual signaling function, like something that birds would do to attract other mates,” says Liliana D'Alba, an evolutionary biologist at the Naturalis Biodiversity Center who was not involved in this study. This finding, published in a recent study in Behavioral Ecology, represents one of the first known examples of birds using cosmetics to communicate between parents and offspring. The birds with the most intense yellow and ultraviolet-colored mouths-an indicator of good immune health-get more worms. Now scientists know the color of those mouths results from a surprising trick that helps the chicks catch their parents’ attention: they make a bright yellow lipstick that shows off their immune health.Ī team of ecologists in Spain found that the color of the chicks’ preen oil, which they take from a gland and apply to the edges of their beaks, influences how much food their parents give them. Like many bird parents, all the adult starlings see when they look down at their chicks is a cluster of circular yellow mouths, each vying for a larger share of food. Tucked inside their nest, the gray baby birds stretch their necks, stick their little faces up in the air, open their beaks wide and cry out insistently. Ageing and Sexing (PDF 4.Spotless starling chicks make quite a sight when they’re hungry.Laboratorio Virtual Ibercaja 417 Spotless Starling Phylogenetic relationships among Palearctic–Oriental starlings and mynas (genera Sturnus and Acridotheres: Sturnidae). ↑ Zuccon, D., Pasquet, E., & Ericson, P.The Birds of the Western Palearctic (Concise ed.). The EBCC Atlas of European Breeding Birds pp. Like most starlings, it is a cavity-nesting species, breeding in tree holes, buildings and in cliff crevices. It is gregarious, forming sizeable flocks, often mixed with common starlings, of up to 100,000 in winter. Like its more common relative, it is an omnivore, taking a wide variety of invertebrates, berries, and human-provided scraps. The population has grown in recent decades with a northward expansion in range, spreading to the whole of Spain (previously absent from the northeast) between 19, and colonising locally along the southern coast of mainland France since 1983. The highest population densities are in open grazed holm oak woods, and in urban habitats such as Gibraltar, where it is common. The spotless starling uses a wide range of habitats and can be found in any reasonably open environment, from farmland and olive groves to human habitation. It is a noisy bird and a good mimic its calls are similar to the common starling's, but louder. Like the common starling, it walks rather than hops, and has a strong direct flight, looking triangular-winged and short-tailed. It can also be confused with the common blackbird ( Turdus merula), which differs most obviously in its longer tail and lack of plumage gloss. Confusion with the common starling is particularly easy during the winter, when common starlings are abundant throughout the spotless starling's range, but also in summer where their breeding ranges overlap in northeastern Spain and the far south of France. Young birds are dull brown, darker than young common starlings, and have a black bill and brown legs. In summer, the bill is yellow with a bluish base in males and a pinkish base in females in winter, it is duller, often blackish. It also differs in having conspicuously longer throat feathers (twice the length of those on common starlings ), forming a shaggy "beard" which is particularly obvious when the bird is singing. The adult spotless starling is very similar to the common starling, but marginally larger (21–23 cm length 70–100 g weight), and has darker, oily-looking black plumage, slightly purple- or green-glossed in bright light, which is entirely spotless in spring and summer, and only with very small pale spots in winter plumage, formed by the pale tips of the feathers.
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