The questions asked were (1) whether claws and toes of birds of prey are actually different from those of other perching birds, and, if so, (2) what parameter can describe such a difference. The structure of toes and claws of the first and third toe was then evaluated in three groups of birds: Falconiformes, Strigiformes and non-raptorial species. One adult male per species was considered, and, among non-raptorial birds, only species belonging to typically or partially perching families. Only one specimen per species was chosen, from museum skin bird collections. All species examined occur in the western Palearctic, according to Cramp & Simmons (1977-1994). Discriminant Function Analysis showed clear separation of the groups. In particular, the first canonical function segregated Falconiformes from Strigiformes, whereas the second separated Strigiformes from non-raptorials. However, Falconiformes and non-raptorials partially overlapped and were not separated. The characteristics segregating Falconiformes from Strigiformes mainly concerned claw curvature, claw length in relation to toe length, and the last phalanx shape, thin or rounded. Characters contributing to segregate Strigiformes from nonraptorials were claw curvature in relation to their radius and the shape, thin or rounded, of both claws and last phalanxes. Results indicate that Strigiformes toes and claws only superficially resemble those of Falconiformes and the shape of claws and toes of Falconiformes are much more similar to those of non-raptorial species than they are to those of Strigiformes.

It has long been held that Falconiformes and Strigiformes possess a strong similarity in their claws due to their adaptive convergence for preying specialisation and that claws differ from those of other bird species, justifying the usual name of talons, instead of claws. It is subjectively felt that talons in birds of prey are very similar and somewhat different from claws of other birds, but the analysis of the geometrical reason for that has been neglected so far. The aim of this study is to answer two questions: (1) whether raptor and owl talons are actually similar, (2) which parameter can describe the similarity or difference. The structure of toes and claws of first (toe-1) and third toe (toe-3) was evaluated in four groups: Strigiformes (suborder Strigi), Accipitridae, Falconidae, for the analysis of difference between birds of prey, and Non-raptorial species, used as out-group. One adult male per species was considered, and, among Non-raptorial birds, only species belonging to typically or partially perching families. Only one specimen per species was chosen, from museum skin collections. The species and families considered were those listed in a reliable worldwide checklist. The multiple discriminant analysis segregated Strigiformes from both Accipitridae and Non-raptorials. The Falconidae, however, had an almost symmetrical overlap on other groups. Function-1 separated Strigiformes from Non-raptorials, mainly involving the section shape of claw-1, claw-3, and of phalax-1, as well as how much claws are hooked in relation to their radius. Function-2 segregated Strigiformes from Accipitridae, basically involving the curvature of claw-1 and also that of claw-3 in relation to its toe length. Our results show that although apparently similar, owls' talons differ in several characters from Accipitrids' and Non-raptorials ones, while Falcons show intermediate characteristics, proving not to have particular specialisation in their talons, in accordance to recent phylogenomic studies.

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Species‐area relationships (SARs) are still the main basis for all projections of extinction rates of species following habitat loss. To investigate spatial‐accumulation patterns of floristic species owing to the degree of species confinement to habitats, we considered 38 parks and reserves in Italy on a wide range of scales, covering about 70% of native flora and more than 21% of the land under legal protection. We used robust methods for multivariate outlier detection to derive the best regression model by checking accordance or lack of accordance with the SAR models even for those observations with no recorded species, which can occur when endemic species are rare. This method enabled us to demonstrate the arbitrariness of omitting observations without endemic species, because only a few such observations proved to be true outliers. As the degree of species confinement to habitat increased, the explained variance in species number and the slope value (z) increased significantly. The stronger the confinement of a species to favorable habitat, the more it was likely to be affected by habitat loss. For species within Italy, those found only within Italy had steeper species‐area slopes than those found more widely. When the analysis was extended to 17 larger areas of the Mediterranean region, a stability for the endemic spatial‐accumulation rate appeared across 15 to 47,000,000 ha. As area increases, the number of species increases, but the number of endemic species increases for more; therefore, a small preserve is expected to contain a large number of species even if it has few or no endemic species. The relatively few reserves we considered captured the country's general species richness far better than they did that of endemic species. We discuss the conservation implications of such results within the context of the national conservation program of the Map of Italian Nature, which is intended to fill the gaps in the existing reserve networks for preservation of species diversity.

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