Pleistocene Park location
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Pleistocene Park is, to quote their website:
"a major initiative that includes an attempt to restore the mammoth steppe ecosystem, which was dominant in the Arctic in the late Pleistocene. The initiative requires replacement of the current unproductive northern ecosystems by highly productive pastures which have both a high animal density and a high rate of biocycling." It was founded by Sergey Zimov, who is a big advocate for de-extinction; by reintroducing mammoths to select areas of Siberia, it will mean the regeneration of its lost steppe ecosystem. When widespread, this habitat played a vital role in controlling the Earth's temperature throughout the year; now that much of it is gone, climate change is advancing at a frightening rate.
The park is currently home to six different species; moose, reindeer, wapiti (elk), horses, musk oxen and bison. The steppe ecosystem will be restored with the presence of a very large herbivore, which will transform the vegetation back to the highly productive grassland it once was: the mammoth. Usually when an animal goes extinct, the remaining species around it evolve to fill the gap that it left behind, so that the ecosystem retains its balance. In the case of the mammoth however, the role that it once played has not been re-filled; the animal closest to doing so currently is the moose, but it is relatively rare in the region due to poaching, and is simply not heavy or destructive enough for regeneration of the highly-productive steppe. This is why it is vital that the mammoth returns for regeneration of the ancient steppe ecosystem. |
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The steppe biome is characterised by flat treeless grassland, a semi-arid climate and high winds (due to being in the interior of continents, away from oceans and surrounded by mountains). The temperature can be highly changeable from day to night and summer to winter. In terms of rainfall, steppe is the link between forest and desert; more rain and it would become a forest, less and it would be a desert.
Thousands of years ago, it had a very high prevalence on our planet. It survived as the most dominant ecosystem on the Earth through countless warm and cold cycles, up until the end of the Pleistocene epoch. Now however, it is disappearing; ploughing of the land for farming, over-hunting of its native species and climate change have all contributed over the years to its degradation. The herbivores that once lived alongside a small amount of predators were now forced off the exposed grasslands into forests by humans with ever-advancing weaponry. These highly productive pastures, without the dense animal life that stopped trees and slow-growing plants taking root, degraded into forests or were occupied by human settlements. |
"Regarding our research on woolly mammoth haemoglobin, briefly, we were able to sequence the two genes (alpha and beta globin) that encode their haemoglobin protein from ancient DNA samples extracted from a mammoth that lived 43,000 years ago. We discovered that the mammoth alpha globin protein differed from that of Asian elephants at one position, while the mammoth beta globin protein differed at three positions. To test for physiological differences in their ability to bind oxygen (especially at low temperatures), we inserted the functional elephant genes into E. coli bacteria using something called an expression plasmid (essentially just a small circular piece of DNA that contained the two elephant genes). We also used a technique called site-directed mutagenesis to convert the elephant DNA so that it precisely matched the mammoth globin gene sequences, and also inserted these genes into the bacteria. The bacteria were then grown in a special broth and induced to express the hemoglobin (which self assembles, making 'authentic' (i.e. identical to) mammoth and elephant hemoglobin). Upon purifying the two proteins, we conducted oxygen binding experiments and were able to determine that the mammoth protein worked better at lower temperatures than the elephant protein. We believe this was adaptive for mammoths, as their extremities (e.g. feet, ears, tail) are expected to be maintained at very low temperatures to minimize heat loss (thus lowering their energy requirements in winter, when it is dark, and food is harder to find and of lower nutritional quality).
Obtaining DNA sequences from recently extinct species like the mammoth is fairly routine now, with at least 4 (nearly) complete genomes being published for mammoths alone in the past couple of years. Interestingly, we have discovered that there was substantial variability in hemoglobin sequences among mammoths. Thus, we hope to soon express these different hemoglobin variants to see if they have similar or different properties.
In addition to mammoths, we have also expressed different hemoglobins (both embryonic and adult) from the extinct Steller's sea cow and great auk, and are soon going to express woolly rhino and mastodon hemoglobins (we have the sequences for these latter two species)."