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The Iranian jerboa (Allactaga firouzi Womochel, 1978) is one of the rarest rodent species in the world and it has been reported exclusively from a single site in central Iran. Because of its restricted geographical distribution and habitat degradation, it has been classified as Critically Endangered in the IUCN Red List. From April 2007 to February 2009 on a small area (2200 ha) of semi-arid grazed steppe (altitude 2000 m, surface covered by bare soil and/or scarce shrub and grass vegetation) we studied the architecture structure of burrow system and burrow site selection of Iranian jerboa. Three types of burrows including temporary burrows, winter and s ummer burrows were detected in the studied habitat. Habitat characteristics such as the percentage cover of: bare soil, pebble and cobble and desert plant species like Anabasis aphylla, Artemisis siberi, and Peganum harmala, as well as the selected chemical soil parameters (content of calcium sulfate, calcium carbonate) were measured in the burrow sites and compared with similar variables measured at random plots in the non-burrow sites. The principal component analysis successfully distinguished between the burrow sites and the non-burrow areas. The burrow site selection was mainly influenced by percentage cover of bare soil, vegetation type, soil texture and chemistry.
Genetic differentiation among 14 populations representing all Egyptian dipodid (jerboa) species and subspecies was examined at 25 structural loci and interspecific relationships are discussed. Of the 25 loci, only 3 were monomorphic, with the same allele fixed in all taxa, 9 loci were monomorphic, but demonstrated intertaxon variation, and only 13 loci were polymorphic. The overall mean number of alleles per locus (A) was 1.23 ± 0.02 and the average percentage of polymorphic loci per taxon (P) was 23%. The overall mean of observed heterozygosity (Ho) was found significantly higher than that of expected heterozygosity (He); the overall means per taxon were 0.25 ± 0.017 and 0.085 ± 0.007. Mean levels of genetic identity (I) were 0.970 ± 0.003 among geographic populations, 0.718 ± 0.022 between subspecies, 0.590 ± 0.030 between congeneric species, and 0.368 ± 0.020 between genera. Phenetic analysis of genetic distance matrix produced a phenogram indicating a close association of Jaculus orientalis Erxleben, 1777 to Jaculus jaculus (Linnaeus, 1758), particularly to its subspecies Jaculus jaculus butleri (Thomas, 1922), and indicating a distinct affinity between these latter two species and Allactaga tetradactyla (Lichtenstein, 1823). Estimates of genetic divergence demonstrated that J. orientalis appears to have shared a more recent common ancestor with J. jaculus than A. tetradactyla. Divergence of these species would have occurred by Miocene (ca 9.6 to 18.7 million years ago). The pattern of relationships of the dipodid species indicated in this study was closely consistent with the hypotheses derived from morphological and chromosomal data.
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