global population is not thought to be declining significantly, so the common starling is classified as being of least concern by the International Union for Conservation of Nature. Taxonomy and systematics The common starling was first described by Carl Linnaeus in his Systema Naturae in 1758 under its current binomial name. Sturnus and vulgaris are derived from the Latin for "starling" and "common" respectively. The Old English , later , and the Latin are both derived from an unknown Indo-European root dating back to the second millennium BC. "Starling" was first recorded in the 11th century, when it referred to the juvenile of the species, but by the 16th century it had already largely supplanted "stare" to refer to birds of all ages. The older name is referenced in William Butler Yeats' poem "The Stare's Nest by My Window". The International Ornithological Congress's preferred English vernacular name is common starling. The starling family, Sturnidae, is an entirely Old World group apart from introductions elsewhere, with the greatest numbers of species in Southeast Asia and sub-Saharan Africa. The genus Sturnus is polyphyletic and relationships between its members are not fully resolved. The closest relation of the common starling is the spotless starling. The non-migratory spotless starling may be descended from a population of ancestral S. vulgaris that survived in an Iberian refugium during an Ice Age retreat, and mitochondrial gene studies suggest that it could be considered a subspecies of the common starling. There is more genetic variation between common starling populations than between the nominate common starling and the spotless starling. Although common starling remains are known from the Middle Pleistocene, part of the problem in resolving relationships in the Sturnidae is the paucity of the fossil record for the family as a whole. Subspecies There are several subspecies of the common starling, which vary clinally in size and the colour tone of the adult plumage. The gradual variation over geographic range and extensive intergradation means that acceptance of the various subspecies varies between authorities. Birds from Fair Isle, St. Kilda and the Outer Hebrides are intermediate in size between S. v. zetlandicus and the nominate form, and their subspecies placement varies according to the authority. The dark juveniles typical of these island forms are occasionally found in mainland Scotland and elsewhere, indicating some gene flow from faroensis or zetlandicus, subspecies formerly considered to be isolated. Several other subspecies have