. Bonner zoologische Beiträge : Herausgeber: Zoologisches Forschungsinstitut und Museum Alexander Koenig, Bonn. Biology; Zoology. J 1 I I 1 1 9 8 7 6 5 4 : The shape of the tip of the wings in two populations of the House Sparrow (from Potapov 1967): 1 - sedentary population in Central Europe; 2 - migrant population (Passer domesticus bactrianiis) in Southern Tadjikistan. All necessary variables for the estimation of wing sharpness can easily be taken from typical collection specimens where the wings are fixed in the naturally closed state. In this position, the wing is easier to measure
. Bonner zoologische Beiträge : Herausgeber: Zoologisches Forschungsinstitut und Museum Alexander Koenig, Bonn. Biology; Zoology. J 1 I I 1 1 9 8 7 6 5 4 : The shape of the tip of the wings in two populations of the House Sparrow (from Potapov 1967): 1 - sedentary population in Central Europe; 2 - migrant population (Passer domesticus bactrianiis) in Southern Tadjikistan. All necessary variables for the estimation of wing sharpness can easily be taken from typical collection specimens where the wings are fixed in the naturally closed state. In this position, the wing is easier to measure than when it is dried in the open state. The reason is that drying of the open wing causes uneven desiccation of tissues, and feathers lose their natural posifion, whereas in normally folded wings this is not the case. For instance, in dried open wings of galli- form birds the first (shortened) secondary forms the. 2 Fig. 3: The shape of the opened wing and position of the first (shortened) secondary (A): 1 - in fresh specimen of Tetrao urogalliis (male); 2 - in dryed specimen of Ceutrocerciis urophasianus (from: Drovetski 1996). hind edge of the wing (,2). Therefore in dried open wings of Galliformes, a notch exists at the junc- tion of primaries and secondaries. Drovetsky (1994) devoted a technically complicated study to this notch, which in reality is an artefact appearing when a wing is dried. In living birds this shortened first secondary lies below the first primary, obviously strengthening the position of the latter (Fig. 3,1). The rear border of the wing of living Galliformes is smooth, without any notch where the primaries pass over to the secondar- ies. In collected specimens with folded wings the longest primary forms the tip and the distance between the primaries can easily be measured. These distances, expressed in percent of the wing length and plotted on a graph, provide a clear picture of the shape of the wing and its sharpness. Wing breadth is measured as
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