Marcus A Koch1, Robert Karl2, Dmitry A German2,3. 1. Department of Biodiversity and Plant Systematics, Centre for Organismal Studies (COS) Heidelberg, Heidelberg University, D-69120 Heidelberg, Germany marcus.koch@cos.uni-heidelberg.de. 2. Department of Biodiversity and Plant Systematics, Centre for Organismal Studies (COS) Heidelberg, Heidelberg University, D-69120 Heidelberg, Germany. 3. South-Siberian Botanical Garden, Altai State University, Lenina Street 61, 656049 Barnaul, Russia.
Abstract
BACKGROUND AND AIMS: Aubrieta is a taxonomically difficult genus from the Brassicaceae family with approximately 20 species centred in Turkey and Greece. Species boundaries and their evolutionary history are poorly understood. Therefore, we analysed bio- and phylogeographic relationships and evaluated morphological variation to study the evolution of this genus. METHODS: Phylogenetic analyses of DNA sequence variation of nuclear-encoded loci and plastid DNA were used to unravel phylogeographic patterns. Morphometric analyses were conducted to study species delimitation. DNA sequence-based mismatch distribution and climate-niche analyses were performed to explain various radiations in space and time during the last 2·5 million years. KEY RESULTS: Species groups largely show non-overlapping distribution patterns in the eastern Mediterranean and Asia Minor. We recognized 20 species and provide evidence for overlooked species, thereby highlighting taxonomical difficulties but also demonstrating underexplored species diversity. The centre of origin of Aubrieta is probably Turkey, from which various clades expanded independently towards Asia Minor, south to Lebanon and west to Greece and the Balkans during the Pleistocene. CONCLUSIONS: Pleistocene climatic fluctuations had a pronounced effect on Aubrieta speciation and radiation during the last 1·1 million years in the Eastern Mediterranean and Asia Minor. In contrast to many other Brassicaceae, speciation processes did not involve excessive formation of polyploids, but displayed formation of diploids with non-overlapping present-day distribution areas. Expansions from the Aubrieta centre of origin and primary centre of species diversity showed adaptation trends towards higher temperature and drier conditions. However, later expansion and diversification of taxa from within the second centre of species diversity in Greece started ∼0·19 Mya and were associated with a general transition of species adaptation towards milder temperatures and less dry conditions.
BACKGROUND AND AIMS: Aubrieta is a taxonomically difficult genus from the Brassicaceae family with approximately 20 species centred in Turkey and Greece. Species boundaries and their evolutionary history are poorly understood. Therefore, we analysed bio- and phylogeographic relationships and evaluated morphological variation to study the evolution of this genus. METHODS: Phylogenetic analyses of DNA sequence variation of nuclear-encoded loci and plastid DNA were used to unravel phylogeographic patterns. Morphometric analyses were conducted to study species delimitation. DNA sequence-based mismatch distribution and climate-niche analyses were performed to explain various radiations in space and time during the last 2·5 million years. KEY RESULTS: Species groups largely show non-overlapping distribution patterns in the eastern Mediterranean and Asia Minor. We recognized 20 species and provide evidence for overlooked species, thereby highlighting taxonomical difficulties but also demonstrating underexplored species diversity. The centre of origin of Aubrieta is probably Turkey, from which various clades expanded independently towards Asia Minor, south to Lebanon and west to Greece and the Balkans during the Pleistocene. CONCLUSIONS: Pleistocene climatic fluctuations had a pronounced effect on Aubrieta speciation and radiation during the last 1·1 million years in the Eastern Mediterranean and Asia Minor. In contrast to many other Brassicaceae, speciation processes did not involve excessive formation of polyploids, but displayed formation of diploids with non-overlapping present-day distribution areas. Expansions from the Aubrieta centre of origin and primary centre of species diversity showed adaptation trends towards higher temperature and drier conditions. However, later expansion and diversification of taxa from within the second centre of species diversity in Greece started ∼0·19 Mya and were associated with a general transition of species adaptation towards milder temperatures and less dry conditions.
Authors: Stephen W Ansell; Hans K Stenøien; Michael Grundmann; Stephen J Russell; Marcus A Koch; Harald Schneider; Johannes C Vogel Journal: Ann Bot Date: 2011-06-28 Impact factor: 4.357
Authors: G Besnard; B Khadari; M Navascués; M Fernández-Mazuecos; A El Bakkali; N Arrigo; D Baali-Cherif; V Brunini-Bronzini de Caraffa; S Santoni; P Vargas; V Savolainen Journal: Proc Biol Sci Date: 2013-02-06 Impact factor: 5.349
Authors: Marcus A Koch; Christoph Dobes; Michaela Matschinger; Walter Bleeker; Johannes Vogel; Markus Kiefer; Thomas Mitchell-Olds Journal: Mol Biol Evol Date: 2005-02-02 Impact factor: 16.240
Authors: Marcus A Koch; Johanna Möbus; Clara A Klöcker; Stephanie Lippert; Laura Ruppert; Christiane Kiefer Journal: Ann Bot Date: 2020-06-19 Impact factor: 4.357