Silene stenophylla | |
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Silene stenophylla growing in Magadan Oblast, Russia | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Order: | Caryophyllales |
Family: | Caryophyllaceae |
Genus: | Silene |
Species: | S. stenophylla |
Binomial name | |
Silene stenophylla Ledeb. (1842) | |
Silene stenophylla is a species of flowering plant in the family Caryophyllaceae. Commonly called narrow-leafed campion, it is a species in the genus Silene . It grows in the Arctic tundra of far eastern Siberia and the mountains of northern Japan. Frozen samples, estimated via radiocarbon dating to be around 32,000 years old, were discovered in the same area as current living specimens, and in 2012, a team of scientists successfully regenerated a plant from the samples. [1] [2]
Silene stenophylla grows in the Arctic tundra of far eastern Siberia and the mountains of northern Japan. [3] It is typically 5–25 cm (2–10 in) tall, has narrow leaves, and a large calyx. [4] It blooms during the summer and has incised petals that are lilac, light pink, or white in color. [3] It is a perennial that grows on stony cliffs and sandy shores. [5] S. stenophylla is one of a few Beringian plant species that did not establish itself in North America. [6]
The specific epithet is derived from the Greek stenos (narrow) and phyllon (leaf) to give "narrow-leaved". [7]
A team of scientists from Russia, Hungary and the United States recovered frozen Silene stenophylla seeds and remains from the Pleistocene in 2007, while investigating about 70 ancient ground squirrel (genera Urocitellus and Geomys ssp ) hibernation burrows or caches, hidden in permanently frozen loess-ice deposits [1] [2] located at Duvanny Yar, on the right bank of the lower Kolyma River in Sakha Republic, northeastern Siberia, in the plant's present-day range. [8]
Using radiocarbon dating, the age of the seeds was estimated at between 20,000 and 40,000 years, dating the seeds to the Pleistocene epoch. [8] The embryos were damaged, possibly by the animals' activity. [8] The research team presented their findings at the Botany & Plant Biology conference in Chicago, Illinois in 2007. [8] The burrows were found 20–40 m (66–131 ft) below the present-day surface. [9] Usually the rodents would eat the food in their larders, but in this case a flood or other weather event buried the whole area. Since the rodents had placed the larders at the level of the permafrost, the material froze almost immediately, and did not thaw out at any time since. [9] More than 600,000 fruits and seeds were located at the site. [10]
The Duvanny Yar section exposes the yedoma ice complex or suite and is studied by many scientists as it represents a key strategic cross-section of Late Quaternary East Siberian stratigraphy [2] [11] [12] and "an important key section for the palaeo-environmental history of the Late Pleistocene Beringia Land, the non-glaciated landmass between the Taymyr Peninsula and Alaska." [13] Near Duvanny Yar is the Pleistocene Park, (Russian : Плейстоценовый парк), a nature reserve on the Kolyma River south of Chersky where an attempt is being made to recreate the northern subarctic steppe grassland ecosystem that flourished in the area during the Last Glacial Period. [14]
In February 2012, a team of scientists from the Institute of Cell Biophysics of the Russian Academy of Sciences announced they had successfully regenerated specimens from fruit that had been frozen for 31,800 (±300) years according to their radiocarbon dating. [9] [15] The accomplishment surpasses the previous record for the oldest plant material brought back to life, of 2000 years set by Judean date palm (Phoenix dactylifera) seeds. [9] The team led by David Gilichinsky used material recovered in 2007 by Stakhov et al. [9] [10] Gilichinsky, who for many years was head of the Geocryology Lab in the Institute for Physicochemical and Biological Problems in Soil Science at the Russian Academy of Sciences in Moscow, died in February 2012, just before the paper was published. He was recognized by the team as a "pioneer in studying microorganisms in Siberian and Antarctic permafrost, his achievement attracted scientists from all over the world to research on permafrost life systems." [2]
Initially, the researchers attempted to germinate mature seeds recovered from the fruit. [9] When these attempts failed, they turned to the fruit itself and were able to culture adult plants from placental tissue. [9] The team grew 36 specimens from the tissue. [10] The plants looked identical to modern specimens until they flowered, at which time the petals were observed to be longer and more widely spaced than modern versions of the plant. [10] The reasons for the observed variations are not known. [9] Seeds produced by the regenerated plants germinated at a 100% success rate, compared with 90% for modern plants. [10]
According to Robin Probert of the Millennium Seed Bank, the demonstration is "by far the most extraordinary example of extreme longevity for material from higher plants" to date. [9] It is not surprising to find living material this old, but is surprising that viable material could be recovered, she added. The Russian scientists speculated that the tissue cells were rich in sucrose which acted as a preservative. [9] They also noted that DNA damage caused by gamma radiation from natural ground radioactivity at the site was unusually low for the plant material's age and is comparable to levels observed in 1300-year-old lotus ( Nelumbo nucifera ) seeds proven to germinate. [10] Probert hopes that the techniques developed in the resurrection of Silene stenophylla may one day be used to resurrect extinct species. [9] Paleontologist Grant Zazula, who has previously disproven claims of ancient regeneration, said: "This discovery raises the bar incredibly in terms of our understanding in terms of the viability of ancient life in the permafrost." [16]
The successful regeneration of the Silene stenophylla plants was cited in 2014 as the inspiration for experiments that discovered a viable giant virus, Pithovirus sibericum , in 30,000-year-old Siberian permafrost; the virus infects amoebas. [17]
Siberia is an extensive geographical region comprising all of North Asia, from the Ural Mountains in the west to the Pacific Ocean in the east. It has formed a part of the sovereign territory of Russia and its predecessor states since the centuries-long conquest of Siberia, which began with the fall of the Khanate of Sibir in the late 16th century and concluded with the annexation of Chukotka in 1778. Siberia is vast and sparsely populated, covering an area of over 13.1 million square kilometres (5,100,000 sq mi), but home to roughly a quarter of Russia's population. Novosibirsk, Krasnoyarsk, and Omsk are the largest cities in the area.
A seed bank stores seeds to preserve genetic diversity; hence it is a type of gene bank. There are many reasons to store seeds. One is to preserve the genes that plant breeders need to increase yield, disease resistance, drought tolerance, nutritional quality, taste, etc. of crops. Another is to forestall loss of genetic diversity in rare or imperiled plant species in an effort to conserve biodiversity ex situ. Many plants that were used centuries ago by humans are used less frequently now; seed banks offer a way to preserve that historical and cultural value. Collections of seeds stored at constant low temperature and low moisture are guarded against loss of genetic resources that are otherwise maintained in situ or in field collections. These alternative "living" collections can be damaged by natural disasters, outbreaks of disease, or war. Seed banks are considered seed libraries, containing valuable information about evolved strategies to combat plant stress, and can be used to create genetically modified versions of existing seeds. The work of seed banks often span decades and even centuries. Most seed banks are publicly funded and seeds are usually available for research that benefits the public.
Permafrost is soil or underwater sediment which continuously remains below 0 °C (32 °F) for two years or more: the oldest permafrost had been continuously frozen for around 700,000 years. Whilst the shallowest permafrost has a vertical extent of below a meter (3 ft), the deepest is greater than 1,500 m (4,900 ft). Similarly, the area of individual permafrost zones may be limited to narrow mountain summits or extend across vast Arctic regions. The ground beneath glaciers and ice sheets is not usually defined as permafrost, so on land, permafrost is generally located beneath a so-called active layer of soil which freezes and thaws depending on the season.
Beringia is defined today as the land and maritime area bounded on the west by the Lena River in Russia; on the east by the Mackenzie River in Canada; on the north by 72° north latitude in the Chukchi Sea; and on the south by the tip of the Kamchatka Peninsula. It includes the Chukchi Sea, the Bering Sea, the Bering Strait, the Chukchi and Kamchatka Peninsulas in Russia as well as Alaska in the United States and the Yukon in Canada.
The Kolyma is a river in northeastern Siberia, whose basin covers parts of the Sakha Republic, Chukotka Autonomous Okrug, and Magadan Oblast of Russia.
The New Siberian Islands are an archipelago in the Extreme North of Russia, to the north of the East Siberian coast between the Laptev Sea and the East Siberian Sea north of the Sakha (Yakutia) Republic, of which they are administratively a part.
Bolshoy Lyakhovsky Island, or Great Lyakhovsky, is the largest of the Lyakhovsky Islands belonging to the New Siberian Islands archipelago between the Laptev Sea and the East Siberian Sea in northern Russia. It has an area of 5,156.6 km2 (1,991.0 sq mi), and a maximum altitude of 311 m (1,020 ft).
The mammoth steppe, also known as steppe-tundra, was once the Earth's most extensive biome. During glacial periods in the later Pleistocene it stretched east-to-west, from the Iberian Peninsula in the west of Europe, across Eurasia to North America, through Beringia and northwest Canada; from north-to-south, the steppe reached from the Arctic southward to southern Europe, Central Asia and northern China. The mammoth steppe was cold and dry, and relatively featureless, though climate, topography, and geography varied considerably throughout. Certain areas of the biome—such as coastal areas—had wetter and milder climates than others. Some areas featured rivers which, through erosion, naturally created gorges, gulleys, or small glens. The continual glacial recession and advancement over millennia contributed more to the formation of larger valleys and different geographical features. Overall, however, the steppe is known to be flat and expansive grassland. The vegetation was dominated by palatable, high-productivity grasses, herbs and willow shrubs.
Yedoma is an organic-rich Pleistocene-age permafrost with ice content of 50–90% by volume. Yedoma are abundant in the cold regions of eastern Siberia, such as northern Yakutia, as well as in Alaska and the Yukon.
There have been several seeds known at different times as the oldest viable seed.
Sergey Aphanasievich Zimov is a Russian geophysicist who specialises in arctic and subarctic ecology. He is the Director of Northeast Scientific Station, a senior research fellow of the Pacific Institute for Geography, and one of the founders of Pleistocene Park. He is best known for his work in advocating the theory that human overhunting of large herbivores during the Pleistocene caused Siberia's grassland-steppe ecosystem to disappear and for raising awareness as to the important roles permafrost and thermokarst lakes play in the global carbon cycle.
The Jarkov Mammoth, is a woolly mammoth specimen discovered on the Taymyr Peninsula of Siberia by a nine-year-old boy in 1997. This particular mammoth is estimated to have lived about 20,000 years ago. It is likely to be male and probably died at age 47.
Pleistocene Park is a nature reserve on the Kolyma River south of Chersky in the Sakha Republic, Russia, in northeastern Siberia, where an attempt is being made to re-create the northern subarctic steppe grassland ecosystem that flourished in the area during the last glacial period.
Yuka is the best-preserved woolly mammoth carcass ever found. It was discovered by local Siberian tusk hunters in August 2010. They turned it over to local scientists, who made an initial assessment of the carcass in 2012. It is displayed in Moscow.
Alphapithovirus, is a genus of giant virus known from two species, Alphapithovirus sibericum, which infects amoebas, and Alphapithovirus massiliense. It is DNA-based and is a member of the nucleocytoplasmic large DNA viruses clade. It was discovered in 2014, when a viable specimen was found in a 30,000-year-old ice core harvested from permafrost in Siberia, Russia.
The Northeast Siberian coastal tundra ecoregion is an ecoregion that covers the coastal plain of the central north region of Siberia in Russia. This coastal region borders the Laptev Sea and the East Siberian Sea, both marginal seas of the Arctic Ocean, from the Lena River delta in the west to the Kolyma River delta in the east. There are several large river deltas in the area that support breeding grounds for 60 to 80 species of migratory birds. The region is in the Palearctic realm, and the tundra biome. It has an area of 846,149 square kilometres (326,700 sq mi).
The East Siberian Lowland, also known as Yana-Kolyma Lowland, is a vast plain in North-eastern Siberia, Russia. The territory of the lowland is one of the Great Russian Regions. Administratively, it is a part of the Sakha Republic (Yakutia).
Retrogressive thaw slumps (RTS), are a type of landslide that occur in the terrestrial Arctic's permafrost region of the circumpolar Northern Hemisphere when an ice-rich section thaws. RTSs develop quickly and can extend across several hectares modifying Arctic coastlines and permafrost terrain. They are the most active and dynamic feature of thermokarst—the collapse of the land surface as ground ice melts. They are thermokarst slope failures due to abrupt thawing of ice-rich permafrost or glaciated terrains. These horseshoe-shaped landslides contribute to the thawing of hectares of permafrost annually and are considered to be one of the most active and dynamic features of thermokarst—the "processes and landforms that involve collapse of the land surface as a result of the melting of ground ice." They are found in permafrost or glaciated regions of the Northern Hemisphere—the Tibetan Plateau, Siberia, from the Himalayas to northern Greenland, and in northern Canada's Northwest Territories (NWT), the Yukon Territories, Nunavut, and Nunavik and in the American state of Alaska. The largest RTS in the world is in Siberia—the Batagaika Crater, also called a "megaslump", is one-kilometre-long and 100 metres (330 ft) deep and it grows a 100 feet (30 m) annually. The land began to sink, and the Batagaika Crater began to form in the 1960s, following clear-cutting of a section of forested area.
Equus lenensis, the Lena horse, is an extinct species of horse from the Late Pleistocene and Holocene of Siberia, Eastern Mongolia, North-Eastern China, and the Korean Peninsula, Some sources have considered it a subspecies of the wild horse.
During the last ice age northeastern Siberia remained a grassy refuge for scores of animals, including bison and woolly mammoths. Then, about 10,000 years ago, this vast ecosystem disappeared as the Ice Age ended. Now, though, the Ice Age landscape is on its way back, with a little help from the Russian scientists who have established "Pleistocene Park.
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