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|This shot taken at Tal Chhapar Black-buck Sanctuary.|
The Great Grey Shrike or Northern Grey Shrike (Lanius excubitor) is a large songbird species in the shrike family (Laniidae). It forms a superspecies with its parapatric southern relatives, the Southern Grey Shrike (L. meridionalis), the Chinese Grey Shrike (L. sphenocerus) and the Loggerhead Shrike (L. ludovicianus). Within the Great Grey Shrike species itself, there are nine subspecies. Males and females are similar in plumage, pearly grey above with a black eye-mask and white underparts.
Breeding takes place generally north of 50° northern latitude in northern Europe and Asia, and in North America (where it known as the Northern Shrike) north of 55° northern latitude in Canada and Alaska. Most populations migrate south in winter to temperate regions. The Great Grey Shrike is carnivorous, with rodents making up over half its diet.
The scientific name of the Great Grey Shrike literally means "sentinel butcher": Lanius is the Latin term for a butcher, while excubitor is Latin for a watchman or sentinel. This refers to the birds' two most conspicuous behaviours – storing food animals by impaling them on thorns, and using exposed tree-tops or poles to watch the surrounding area for possible prey. Use of the former by Conrad Gessner established the quasi-scientific term lanius for the shrikes. Linnaeus chose his specific name because the species "observes approaching hawks and announces [the presence] of songbirds" as he put it. This habit was also put to use in falconry, as fancifully recorded by William Yarrell later.
The species was first scientifically described by Carl Linnaeus in his 1758 edition of Systema Naturae under the current scientific name. His description is L[anius] cauda cuneiformi lateribus alba, dorso cano, alis nigris macula alba – "a shrike with a wedge-shaped white-bordered tail, back grey, wings black with white spot". At that time, none of the other grey shrikes – including the Lesser Grey Shrike (L. minor), for which the description of the tail pattern is incorrect and which some authors already recognized as distinct – were considered separate species by Linnaeus, but that was to change soon. Linnaeus' binomial name replaced the cumbersome and confusing descriptive names of the earlier naturalist books he gives as his sources: in his own Fauna Svecica he named it ampelis caerulescens, alis caudaque nigricantibus ("light-blue waxwing, wings and tail blackish"), while it is called pica cinerea sive lanius major ("ash-grey magpie or greater shrike") by Johann Leonhard Frisch, who in his splendid colour plate confused male and female. But most authors cited by Linnaeus – Eleazar Albin, Ulisse Aldrovandi, John Ray and Francis Willughby – called it lanius cinereus major or similar, which is a near-literal equivalent of the common name "Great Grey Shrike". The type locality of Linnaeus is simply given as Europa ("Europe").
The shrike family (Laniidae) is a member of the Corvoidea, the most ancient of the four large songbird superfamilies. Among its superfamily, the closest relatives of the Laniidae are probably the Corvidae (crows and allies). Little reliable data exists on its evolution; certainly (even though the supposed ancestral shrike "Lanius" miocaenus might not belong in the Laniidae, and probably does not belong in the same genus as L .excubitor) the genus dates back to Miocene times. A Lanius fossil from the Late Miocene Turolian age, c.6 Ma (million years ago), has been found at Polgárdi (Hungary). Its relationship to the modern species is unclear. However, all things considered, the grey shrike lineage probably represents the Holarctic sister to the African radiation of fiscal shrikes. These two seem to have originated in a west- or southwestward expansion from the genus' origin, which (considering the biogeography of living Lanius lineages) was probably somewhere between Asia Minor and Central Asia. At the time of the Polgárdi fossil, it is rather likely that the grey shrikes were a distinct lineage already; given that they and the fiscals generally follow Bergmann's Rule, the smallish fossil makes an unlikely ancestor to the large grey shrikes even when taking into account the somewhat warmer Miocene climate.
The grey shrike superspecies consists of L. excubitor and its parapatric southern relatives. As mentioned above, the other members of this group are the Southern Grey Shrike (L. meridionalis), the Chinese Grey Shrike (L. sphenocerus) and the Loggerhead Shrike (L. ludovicianus). The center of this group's radiation is probably in the eastern Mediterranean region, and the Southern Grey Shrike represents the basalmost form. The other three only diverged during the expansion into temperate regions. This must have happened fairly recently, because lineage sorting is not complete in the grey shrikes, and most of the present-day habitat of L. excubitor was uninhabitable during much of the Quaternary glaciation. Because of the phylogenetic uncertainties surrounding this close-knit group in the absence of a good fossil record, some refrain from splitting them up into distinct species; most modern authors do so however.
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