The concept of climate variability facilitating adaptive radiation supported by the “Court Jester” hypothesis is disputed by the “Red Queen” one, but the prevalence of one or the other might be scale-dependent. We report on a detailed, comprehensive phylo-geographic study on the ∼4 kb mtDNA sequence in underground blind mole rats of the family Spalacidae (or subfamily Spalacinae) from the East Mediterranean steppes. Our study aimed at testing the presence of periodicities in branching patterns on a constructed phylogenetic tree and at searching for congruence between branching events, tectonic history and paleoclimates. In contrast to the strong support for the majority of the branching events on the tree, the absence of support in a few instances indicates that network-like evolution could exist in spalacids. In our tree, robust support was given, in concordance with paleontological data, for the separation of spalacids from muroid rodents during the first half of the Miocene when open, grass-dominated habitats were established. Marine barriers formed between Anatolia and the Balkans could have facilitated the separation of the lineage “Spalax” from the lineage “Nannospalax” and of the clade “leucodon” from the clade “xanthodon”. The separation of the clade “ehrenbergi” occurred during the late stages of the tectonically induced uplift of the Anatolian high plateaus and mountains, whereas the separation of the clade “vasvarii” took place when the rapidly uplifting Taurus mountain range prevented the Mediterranean rainfalls from reaching the Central Anatolian Plateau. The separation of Spalax antiquus and S. graecus occurred when the southeastern Carpathians were uplifted. Despite the role played by tectonic events, branching events that show periodicity corresponding to 400-kyr and 100-kyr eccentricity bands illuminate the important role of orbital fluctuations on adaptive radiation in spalacids. At the given scale, our results supports the “Court Jester” hypothesis over the “Red Queen” one.
Chromosome banding (G-, C-and Ag-NOR) analysis was carried out on 27 specimens of Sphalax ehrenbergi from seven localities and two specimens of S. leucodon from one locality, all from Turkey. No chromosomal variation was detected in S. ehrenbergi populations from Elazig, Siverek, Diyarbakir and Birecik having the same diploid numbers (2n = 52) and morphology of chromosomes (NFa = 72). The karyotypes of mole rats from Tarsus and Gaziantep possessed the identical diploid number (2n = 56) but different numbers of autosomal arms: NFa = 68 in the Tarsus and NFa = 78 in the Gaziantep populations. Chromosomes of S. leucodon from Malatya (2n = 60, NFa = 74) differed distinctly in the C-banding pattern from all S. ehrenbergi cytotypes by the almost entire absence of heterochromatin in acrocentric autosomes and the presence of heterochromatin arms in subtelocentric autosomes. Nucleolar organizing regions were found mainly on three pairs of chromosomes, but some differences in their localization were revealed. Comparison of G-banded chromosomes showed, that most chromosomes have a similar pattern. The types of chromosomal rearrangements were revealed due to the banding methods.
Mole voles, genus Ellobius, are Palearctic region animals distributed from East Anatolia to Mongolia (1-8). Gromov and Baranova (9) stated that the genus Ellobius has existed since the mid-Pleistocene. Pleistocene remains of Ellobius spp. were found from Konya-Akflehir-Dursunlu in Turkey (10).
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