By Byron Perry
Imagine a grassland stretching to the horizon, teeming with wooly mammoths, rhinoceroses, bison, horses, wolves and tigers, at levels of abundance comparable to the African Serengeti. This was not the Serengeti. It was the Mammoth Steppe, a vast swathe of grassland stretching from Spain to Canada and from the Arctic Ocean to China. It was the planet’s largest biome but was rapidly destroyed around 12000 years ago, likely by human overhunting. However, a family-led team of scientists believe that they can restore the Mammoth Steppe, and even combat climate change at the same time...
The Pleistocene is an epoch of time stretching from 2.58 million years ago - 11700 years ago, covering a series of ice ages, the end of the last one marking the end of the Pleistocene. The Mammoth Steppe was a thriving ecosystem for almost 100,000 years before being rapidly replaced by far less productive tundra ( areas containing small shrubs, due to the extreme cold conditions. For instance, mosses and ferns.)and taiga( forests, that are mostly dominated by coniferous trees). The exact reason for the destruction of the Mammoth Steppe is unclear, but it is highly likely that humans spreading northwards were the cause. The Mammoth Steppe was covered by grasses and herbs, these plants are easily digested by herbivores, in turn supporting the massive populations of large herbivores that characterized the Mammoth Steppe. These herbivores physically destroyed slow-growing plants such as mosses, shrubs and trees by eating and trampling young plants. This symbiotic (mutually beneficial) relationship sustained the Mammoth Steppe. However, when humans arrived from the south they quickly began overhunting the animals of the steppe. With a dramatic population drop in the large herbivores that destroyed the slow-growing plants within a few centuries mosses, shrubs and trees had taken over the steppe, transforming it into the tundra, and causing the extinction of the mammoths, rhinos, bison, tigers and wild horses that lived on the steppe. In many parts of the world, forests have the most abundant wildlife, think of the tropical rainforests. However, this is categorically untrue in the Arctic. Bones preserved in the permanently frozen ground reveal that the steppe had at least 100 times the animal density of the tundra. For every square kilometre of grassland, there was at least 1 mammoth, 5 bison, 6 horses and 10 reindeer!
Pleistocene Park is located in the far North East of Russia, Siberia. Founded in 1996 by Russian scientist Sergey Zimov, and also run by his son Nikita Zimov. The Park is an experiment to see if the Steppe can be restored by reintroducing large herbivores. These herbivores will trample and destroy the slow-growing mosses, shrubs and trees and thus make it possible for grasses to return and the steppe to be restored. The first animals to be introduced were animals already present in the area: reindeer, elk/moose and Yakutian horses, a highly cold adapted breed of horses. From 2010 animals from farther away have been introduced: the highly cold adapted Kalmykian cows and Edilbaevskaya sheep, yaks, wisents/ European bison from other parts of mainland Russia, muskoxen from Wrangel Island in the Arctic Ocean and American steppe bison from Denmark. The Park plans to continue introducing more herbivores, in the short term they plan to acquire more bison and muskoxen. Eventually, carnivores such as tigers will be needed to control the herbivore population. Over the twenty years since the experiment has been running, grass has become the dominant vegetation in many areas, and the area is well on the way to becoming true grassland.
One possibility once in the realms of science fiction, that has recently become possible due to advances in genetics is de-extinction. Mammoths and other extinct species could be cloned from DNA preserved in the frozen Arctic. Another possibility is genetic modification of Asian or African elephants to equip them with thick fur coats, in effect creating a new wooly mammoth species. The reintroduction of mammoths would have a profound effect on the landscape. Elephants uproot trees and with their massive bulk destroy slow-growing vegetation with ease, transforming the tundra into a steppe faster than any living animal.
What does this have to do with climate change?
The region of Earth in which the Mammoth Steppe once existed is covered with permafrost, a word used to describe areas where the ground is frozen year round. This permafrost works as a natural freezer, preserving animals and plants before they can be decomposed. When permafrost melts, as is happening increasingly due to climate change, bacteria start to decompose this organic matter. This produces methane, a greenhouse gas 28 times more potent than carbon dioxide causing further global warming. The permafrost contains 3 times the carbon than all the world's forests and 2 times the carbon in the atmosphere currently. Melting of the permafrost would be catastrophic. Restoration of the steppe would help counter climate change in three main ways. The first is the albedo effect, light surfaces reflect more light than dark ones. Currently, sunlight hitting the Arctic hits dark trees and shrubs, absorbing more heat in the process and thus heating the ground. Sunlight hitting a grassland would strike light snow and grass, reflecting more energy back into space than the tundra. The second is that somewhat counterintuitively snow helps melt the permafrost. This is because winter is far below freezing in the Arctic Region, meaning that a thick layer of snow helps insulate the permafrost from the 5°C (9°F) cooler air temperature, keeping in the heat the permafrost absorbed in the summer. The third is that grasses form deeper root systems than current vegetation, storing more carbon in the process.
Pleistocene Park is an extremely exciting project and one that holds great promise. It has been listed on Project Drawdown’s ‘Top 100 most substantive solutions to global warming.’ It also offers an opportunity to not just conserve wildlife but add to it, by creating new habitat, instead of just preserving what is left.
Pleistocene Park. “Scientific Background.” Pleistocene Park, 29 March 2019, https://pleistocenepark.ru. Accessed 21 March 2021.
Pleistocene Park Foundation. “Pleistocene Park Foundation.” Pleistocene Park Foundation, 8 January 2019, https://pleistocenepark.org/. Accessed 21 March 2021.
Macias-Fauria, Marc, et al. “Pleistocene Arctic megafaunal ecological engineering as a natural climate solution?” The Royal Society Publishing, The Royal Society Publishing, 27 January 2020, https://royalsocietypublishing.org/doi/10.1098/rstb.2019.0122#d3e573. Accessed 21 March 2021.