Biodiversity of the Baltic postglacial ecosystems: CHANGES IN TIME AND SPACE Vytautas...
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Transcript of Biodiversity of the Baltic postglacial ecosystems: CHANGES IN TIME AND SPACE Vytautas...
Biodiversity
of the Baltic postglacial ecosystems:
CHANGES IN TIME AND SPACE
Vytautas Kontrimavičius
Lithuanian Academy of Sciences
Pleistocene glaciations in the northern hemisphere
The gray areas represent ice shields
Approximate appearance of Bering Land Bridge during late Pleistocene time (after Rausch, 1994)
The dotted areas – ice
The white areas – land
Eastern Palearctic Biodiversity
• Ecosystems of the Eastern Palearctic
– have not been covered with Pleistocene glaciations
– therefore their biodiversity is much higher than biodiversity of the Western Palearctic (including European) ecosystems
Western Palearctic Biodiversity
• Postglacial ecosystems of Western Palearctic– are relatively species-poor
– are formed continuously up to now due to
natural expansion of species ranges
anthropogenic transfer
Baltic Biodiversity
• Feature of ecosystems of the Baltic region:
– south-western distribution limit of northern and Siberian species of Taiga and Tundra biomes
– north-eastern distribution limit of Western-European species of deciduous forest biome
The tundra birch(Betula nana)
Europeanhornbeam(Carpinus betulus)
Cloudberry(Rubus chamaemorus)
Mistletoe(Viscum album)
Mountain hare (Lepus timidus)
Fat dormouse (Glis glis)
Pond turtle (Emys orbicularis)
Whitefish:Coregonus lavaretus
Coregonus albula
Tree frog (Hyla arborea)
Baltic Biodiversity
• Combination of northern and southern species in ecosystems– increases their stability in variable
seasonal climate
however– may cause large-scale changes
(extinctions, migrations) in case of long-term climate change
Baltic Biodiversity
• Molecular methods in ecology provided the new possibilities:– study of ecosystem structure– study of population structure within species
• They revealed the genetic heterogeneity of populations in the Baltic region
Microtus agrestis sampling sites
Southern
Western
Eastern
Microtus agrestis postglacial expansion
Microtus agrestis similarity of populations
Southern
Western
Eastern
Lithuania
Lithuania
• The listed data on the population structure of the Baltic region seem to be the only available up to now.
• Therefore, the Baltic region of Europe remains one of the least researched in the aspect of phylogeography
Baltic Biodiversity
• The latest data – disprove the hypothesis of Hewitt (1999) that
the postglacial biota of Europe has been mainly formed by the populations of the southern refugia
– reveal that the northern Europe, including the Baltic region, has been colonized by migration from remote eastern populations of southern Siberia
Baltic Biodiversity
• The questions solved by the molecular ecology:
Population structureGenetic divergenceHybrid zonesSpeciationSibling speciesIntraspecific systematics
Molecular ecology
• They all are questions of biodiversity
• Most intensive research conducted during last 15 years. Publications:
Molecular EcologyMolecular Biology and EvolutionMolecular Phylogenetics and EvolutionGeneticsMolekulyarnaya Biologiya
etc.
Molecular ecology
• In Lithuania, there were little possibilities to conduct molecular ecology research due to economic reasons,
however, recently
Molecular ecology
• a laboratory of molecular ecology has been equipped in the Institute of Ecology of Vilnius University
• a field material has been collected for the phylogeographic studies of
ProtistaVermesMolluscaInsectaAvesMammalia
Molecular ecology in Lithuania
Molecular ecology in Lithuania
• The main research trends:
structure of populations
intra-specific hybrid zones
significance of the European and Siberian refugia in the formation of post-glacial biota of Northern Europe
Thank you for attention!