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Territoriality in breeding Whitethroats were examined on colour-ringed individuals in two areas located in different geographical regions: Low Volga and Caucasus coast of the Black Sea. In the Caucasus region 29% of males were polyterritorial (6% — bigynous) whereas in the Volga region no cases of males polyterritoriality nor bigyny were observed. Literature reveals that in regions, where polygyny in the Whitethroat was observed, the breeding period is short and the species has only one breeding cycle in a season. In the areas where the breeding period is long, bigyny has not been found, but cases of double- broodness was observed. Author suggests that bigyny in the Whitethroat evolved as a response to the short breeding season, which does not allow males to have two successive broods in a season. The only way to increase their reproductive success is to establish a second territory immediately after the first female starts to lay.
On the example of ciliates of the genus Trichodina the role of extensive faunistic investigation for recognition of morphological variation in parasitic Protozoa is considered. In the paper the results of studies on Trichodina ranae, T. reticulata, T. pediculus and Semitrichodina sphaeronuclea f. macrodentata are summarized with particular attention paid to ecological and geographical aspects of the variation. The evolutionary aspect of these studies is also emphasized.
Geographic variation in egg measurements (egg breadth, length, volume and shape index), was studied in Lapwing, based of the published data from Europe and Asia. Egg size was found to vary significantly with geographic location. Mean egg breadth and volume decreased with longitude and increased with latitude, and this relationship explained 42% and 49%, respectively of their variation among study areas. Mean egg length, and to lesser extent egg shape index, showed an U-shaped relationship with longitude, accounting for 29% and 20%, respectively of their variation between localities. The resultant NW- SE dine in egg size was well pronounced in Europe, with largest eggs laid in Great Britain, N Spain and Norway and smallest in SE Europe. Lapwings breeding in Asia laid eggs consistently narrower and less voluminous than European breeders. In E Asia egg length was however almost as long as in NW Europe. The geographic pattern in egg size corresponds with gradient in oceanic characters of the climate. Precipitation and temperature were suggested as possible factors affecting — via the level of food resources available to laying females — geographic variation in Lapwing egg size. Clinal variation in female body size might be another contributing factor.
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