Role of the Taurus way in the formation of Anatolian biodiversity: Biogeography of the genera Parapholidoptera and Aparapholidoptera

The glacial refuge function of Anatolia in the Western Palearctic has been a determining factor in the biodiversity of a wide geography. Particularly, the elevation lines in Anatolia have provided favorable habitats for mountain species in the southern latitudes. In this context, the topographic feature known as the Taurus Way is noteworthy. This way, which encompasses the elevations that form the Anatolian Diagonal in the northeast, continues with the Taurus Mountains and is associated with the elevations in the Levant region in the south, and further continues towards the Balkans along the fragmented elevation line in the Aegean, has been demonstrated to host a biodiversity hotspot through numerous studies. However, the functioning of the Taurus Way and its biogeographic contribution has not been comprehensively addressed. Within the scope of the planned doctoral thesis, the effect of the Taurus Way on the mountain biodiversity of Anatolia has been examined from both genetic and ecological perspectives through the phylogeography of Parapholidoptera and Aparapholidoptera. For molecular analyses, mitochondrial COI and ND2 genes, as well as nuclear ITS1-ITS2 genes, were sequenced using Sanger sequencing method to generate data sets. The data sets represented twenty five populations of ten phenotypic species of Parapholidoptera and three populations of three species of Aparapholidoptera, respectively. In addition to individual genes, a combined COI+ND2 (MTM) data set was generated, resulting in a total of four separate data sets. Molecular data were used to infer i) the phylogeny of the genera, ii) the diversification times of the genera, iii) tests for species boundaries and genetic species, and iv) the location of the ancestral stock population of Parapholidoptera. While Aparapholidoptera is distributed in the northern half of the Anatolian Diagonal, Parapholidoptera shows a typical distribution along the Taurus Way and was therefore preferred in biogeographic analyses. The total distribution of Parapholidoptera genus was divided into six biogeographic regions, including Marmara and Northwest Anatolia, Aegean, Southern Taurus Mountains, Anti-Taurus Mountains, Central Northern Anatolia, and Lesser Caucasus, and analyzed separately. Ecological analyses included character evolution tests for Parapholidoptera genus using current presence data and ecological niche modeling for both Parapholidoptera and Aparapholidoptera, in order to examine how the complex structure of the Taurus Way, divided by peaks and valleys, may have influenced diversification. The findings of the thesis have revealed that the reciprocal monophyly of P. spinulosa, P. castaneoviridis, P. signata, and A. kosswigi species is not supported, indicating the need for taxonomic revision considering both phenotypic and genetic characteristics within the genera. Phylogenetic analyses suggest the presence of eighteen genetic species for Parapholidoptera and three genetic species for Aparapholidoptera. Time-calibrated phylogenetic trees indicate that both genera share a common ancestor during the Messinian period, and the diversification has been driven by Pleistocene climate cycles. Biogeographical analyses suggest that the ancestral population of the genera originated from a stock population in Central Northern Anatolia and Anti-Taurus Mountains region. Towards the terminal branches, the Central Northern Anatolian lineage diversified internally, while the Anti-Taurus lineage became the founder of all other populations along the Taurus Way. Principal component analysis of ecological characters, including six ecological traits that explain the variation of bioclimatic parameters, with elevation being one of the five variables, suggests that these characters evolved according to Brownian Motion (BM) and Ornstein-Uhlenbeck (OU) models, indicating the preservation of the ancestral state. Phylogenetic signal was only found for seasonality among the characters related to temperature, precipitation, thermality, and seasonality. Ecological niche modeling based on nineteen bioclimatic parameters for four different time periods, including the last interglacial, last glacial, 1970, and 2070, revealed that the Taurus Way has undergone both vertical and horizontal distribution changes. Since the main objective of the thesis was to test the Taurus Way hypothesis, the taxonomic revision was beyond the scope of the study. The results on the biogeography of diversification suggest that the Amanos Mountain range, located in the southeast of the Taurus Way and the southern boundary of the Anatolian Diagonal, has played an active role in faunal/floral exchange between Anatolia and the Levant. The findings also support the hypothesis that Anatolia served as a glacial refuge for many montane species. Ecological data highlight the diverse climatic niches harbored within the Taurus Way, which has played an important role in both the preservation of biodiversity within Anatolia and faunal exchange with neighboring regions through vertical distribution changes and horizontal distribution changes.