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In our research we tried explain the high genetic similarity among modern Wisent and domestic cattle. The genetic material was taken from different species of Bovidae family including aurochs. The control region of mitochondrial DNA and the sequence of gene 16S rRNA were subject to analyses. To compare the species we estimated genetic distance and constructed phylogenetic tree. The high level of similarity between wisent and aurochs found in our work suggests that hybridization and crossing of wisents and aurochsen must have had their place before domestication of the Bos taurus ancestor.
A sample of newly hatched American colubrids, divided according to their level of domestication, understood herewith as the generation history in captivity, was tested in an open field test (OFT) for degree of activity and confidence in open terrain and in confrontation with individuals of such species as Pantherophis guttatus and Lampropeltis getula splendida as well as L. g. californiae, in order to compare their antagonistic and feeding behaviour reactions. The cluster comparison of defence reactions revealed no effect of domestication (many generation in captivity) in the face of potential danger. Even albino phase Kingsnakes, considered to be the form of this species most affected by captivity (altered genome), maintained their natural feeding response. The degree of activity in OFT conditions was seen to decrease with the snakes' age. Thus it was demonstrated that captive specimens bred in terrariums may be considered a gene bank for ex situ conservation strategy. However it is recommended that specimens as young as possible should be used in reintroduction to natural habitat, as these will respond most faithfully to the pressure of natural selection, based on their behavioural variation not supressed by apathy caused by captivity.
Population of field vole in Southern Poland represents triennial cycle of numerical force. Regarding to this the free living vole population was tested in reference to two hypothesis of Carnov and Finerty (1980) and Lambin and Krebs (1991a), according to which the cyclic changes of sizes in population were dependent on changes of their inter individual genetic relationship. In 1999-2001 when phases of number decrease (low phase) and increase (high phase) took their places we carried out the analysis of inter individual kinship in summer and autumn seasons (1999 and 2000), and spring season 2001 on one hectare of sampling area. Basing on the places of trapping, the individuals were grouped (or not) in aggregations. Nevertheless because of low number of captures, the aggregations could be defined for summers 1999 and 2000 only. The tissue samples of 68 Microtus agrestis individuals (50 females and 18 males) were taken. RAPD method with three primers was applied for DNA analysis. The total number of fragments obtained, and the frequency of every single fragment were calculated for each starter. No difference in kinship among the individuals belonging neither to the same nor to the different populations was detected. This may suggest that during summer seasons genetic relations do not play any important role on vole's dispersion. Higher level of kinship was found in the increase phase than in decrease one, in accordance with model of Lamin and Krebs (1991a) but not with that of Charnov and Finerty (1980). Kinship of individuals trapped in spring was twice as high as of that in summer and autumn and kinship among males was lower than among females.
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