## 3 Results and Discussion
### Comparison with Other Palearchive Data  
Environmental archives such as lake and marine sediments, peat bogs, glacial ice, and tree rings are widely used to reconstruct Hg accumulation at the local, regional, and global scale. All archives have their advantages and disadvantages, but none of them is a definite record of past mercury levels, because of the complexity of the mercury cycle's being influenced by various processes in each archive [63; 64]. Most archives record the past several hundred to several thousand years (ice cores, peat bogs, lake and marine sediment cores, and tree rings), whereas long-term paleorecords recording up to a hundred thousand years are scarce (ice cores of Antarctica and Greenland, sediments cores and speleothems). Ice Age animals in this study lived 45 up to 10.5 kyr BP. Animals were exposed to mercury from the diet and the environment. The natural sources of Hg emissions were volcanoes, air-sea and soil-vegetation-air exchange, biomass burning (wildfires), and the revolatilization of deposited Hg from the soils (including release associated with permafrost thawing due to climate change). The highest Hg concentration recorded in this study dates to 33.930 cal kyr BP. The other peak of Hg concentration at 23.292 cal kyr BP falls into the LGM period. An increase of mercury concentrations in hair coincides with variations of Hg concentrations and depositions recorded in the Antarctica Dome C ice core (Figure 4). Due to constant snow accumulation, Hg concentrations and fluxes change synchronically. Total Hg and Hg\({}^{2+}\) concentrations are also characterized by similar trends, except during the initial period from 15 to 2 kyr BP. The highest peak occurred during the Karpinian interstadial of the Late Pleistocene, the period of maximum insolation in 200 ka years [65]. The presence of mosses in Malykhchinsky bison's food masses indirectly indicated a significant wetland area in this period because of significant climate warming. Hg increase in environment caused by rapid release of mercury during thawing periods was recorded in other paleoarchives, such as sediments in Limnopolar Lake (South Shetland Islands), where extraordinary high Hg enrichment was observed [65]. Research based on about 600 samples from soil permafrost cores (Alaska) discovered that the active layer is the largest Hg pool on the planet. The Northern Hemisphere permafrost region contains 1656 \(\pm\) 962 Gg Hg, of which 793 \(\pm\) 461 Gg is frozen in permafrost. The active layer and permafrost contain nearly twice as much Hg as all other soils, the ocean, and the atmosphere combined [66]. This allows us to assume that, in the past warm climatic periods, thawing permafrost caused significant mercury to be released into the environment, from the active layer of permafrost. The exogenous Hg in hair of ancient animals is mainly due to its sorption on the hair surface, from the atmosphere. The endogenous Hg in hair also can be due to Hg\({}^{0}\) influx. Elemental mercury (up to 80% of inhaled Hg\({}^{0}\) vapors) is absorbed in the lungs, quickly diffused into the blood, and distributed to all organs of the body; it also accumulates in growing hair. The second peak corresponds to the Last Glacial Maximum, where the Antarctic record also shows a drastic increase in Hg concentrations during the LGM. It was found for mercury in the Antarctic [67] that the oxidation of gaseous mercury by sea-salt-derived halogens occurred in the cold atmosphere. The oxidized mercury compounds were then transferred to the abundant mineral dust particles and deposited. A significant correlation between dust concentrations and changes of temperature during glacial periods was confirmed by comparing dust and stable isotope, up to 90% of the dust variability can be explained by the temperature variations. The deposition of dust in Antarctica during glacial periods is about 20 times higher than during interglacialis [68].