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Allozyme variability and fluctuating asymmetry (FA) in skull morphology were used to test the hypothesis of inbreeding in an isolated springbok Antidorcas marsu­pialis fZimmermann, 1780) population from the Chelmsford Nature Reserve, South Africa. Of 39 loci studied in a sample of 30 animals, five displayed allelic polymorphism. Average heterozygosity of 1.8% was not appreciably lower than a value of 2% calculated for 49 animals from a control group from Beniontein Game Farm in the Northern Cape Province, South Africa. Proportion of polymorphic loci and average number of alleles per locus were identical in both populations (10.3% and 1.1). Morphological analysis contradicted the prediction of increased fluctuating asymmetry due to the likelihood of inbreeding in a small, isolated population, with FA almost always higher in the control compared to Chelmsford. Chelmsford animals were however smaller than control animals for seven out of 9 cranial and horn variables analysed (significantly so in four cases), hich could conceivably be explained by environmental influences. It is concluded that loss of genetic diversity is not a problem in the Chelmsford springbok population, although this does not negate the possibility that physical deformities occurring in the population may indeed be genetically induced.
Biochemical-genetic variation was studied in springbok Antidorcas m. marsupialis (Zimmermann, 1780) from a large (N > 2000) "wild" population (n = 24) and a small (30 > N > 20) isolated farm population (n = 10) using electrophoretic allozyme analysis. Springbok showed polymorphisms at eight out of 46 loci. The springbok from the large population had a higher proportion of polymorphic loci (P = 15.6%) than those from the small population (P = 8.9%). Average heterozygosity (H = 5.1% and H = 4.1%, respectively) was similar for the two populations. This unexpected result is an artefact of the method for calculating H. H:P ratios are lower for the large population than the small one. The distribution of genotypes differed significantly from Hardy-Weinberg equilibrium for two loci. These were found to have a preponderance of homozygotes. This could not be explained by population fragmentation. The levels of polymorphism and heterozygosity are high compared to results from other African bovids.
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