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There is a huge number of small lakes in south of West Siberia and such lakes are very useful local for climate and environmental reconstructions. The previously studied objects in the area are mostly peat-bogs and geologic sections; the lake history and natural interactions between paleoenvironmental and climate changes in the region are understudied. Here we present results of multiproxy investigation of three lakes located in different parts of the Baraba forest-steppe region along a 300km north-south transect: Bolshie Toroki, Chany (Yarkov subbasin), and Malye Chany. Vibrational drilling technology method was used to recover undisturbed columns of lake sediments and penetrate to non-lacustrine substrata. The obtained cores were investigated basically by sedimentological and palynological analyses (with the reconstruction of vegetational cover) and radiocarbon dating, additionally we used other paleontological (diatom, ostracod, chironomid analyses), geophysical, and biogeochemical methods to obtain information about environmental and climate changes, as well as lake level, biotic, ecosystem, and geochemical changes. This and our previous studies showed complicated picture of lake evolution histories and climate change in the south of West Siberia. According to our data most of investigated lakes (Chany, Malye Chany, Beloye, Minzelinskoye, Bolshie Toroki, and Kirek) are very young and started to form in the middle Holocene or later as marshy lowland with peaty sediments. Then they became deeper with mostly sapropel sediments.

In August 2010, a well-preserved Mammuthus primigenius carcass was found along the coast of Oyogos Yar in the region of the Laptev Sea and the mummy was nicknamed ‘Yuka’. Frozen sediment samples from the area of skull condyles were collected for pollen and plant macrofossil analyses. The results from the palaeobotanical investigation confirmed that the Yuka mammoth lived during the optimum of the Kargin Interstadial (MIS3). The burial place of the mammoth could have been a small shallow freshwater pond with either stagnant or slowly moving water. The vegetation of the Oyogos Yar in MIS3 optimum was probably represented by zonal tundra-steppe combined with mesic-xeric meadows.

Pollen, botanical macrofossils, chemical components and ancient DNA were studied in samples from the rumen of a frozen Yakutian bison (Bison priscus) that lived ca. 10,500 cal a BP. The dialkyl glycerol ether lipid archaeol (2,3-di-O-phytanyl-sn-glycerol) was detected and is interpreted to have been derived from methanogenic Archaea in the rumen. This is the oldest reported occurrence of archaeol attributed to digestive tract Archaea. Remains of shrubs (Alnus, Betula, Salix) and Poaceae indicate that the animal probably lived in a landscape of predominantly dry soils, intermixed with wetlands containing herbaceous plant species, as indicated by remains of Comarum palustre, Caltha palustris, Eriophorum, Sparganium, Menyanthes trifoliata and Utricularia. All recorded taxa still occur in the present-day Yakutian tundra vegetation. We discuss the representativeness in space and time of the methods used. Both the botanical microfossil and the macrofossil records may be biased because of differences in pollen production and dispersal between species, the food choice of the bison, and the season of death of the animal. Similarities and differences are discussed to highlight pitfalls of the individual analytical techniques. We highlight the power of data integration.

The last meal of a horse that lived in the northern part of the Sakha Republic (Russia) c. 5400 years ago was studied using pollen, spores, botanical macroremains, lipid composition, and ancient DNA in order to reconstruct its components. Pollen of Poaceae was superabundant, but this may be because of over-representation as a consequence of grazed inflorescenses of grasses. We evaluate the paleo-environmental indicator value of the different methods applied. Botanical macrofossils and chemical data show what the animal had eaten. Pollen grains and the aDNA record also give information about taxa that occurred elsewhere in the landscape. The combined data point to an open landscape of a coastal tundra dominated by graminoids (Poaceae, Cyperaceae) with a limited amount of Birch and Alder.