Latest news with #Cryogenian
eNCA
8 hours ago
- Science
- eNCA
How did life survive 'Snowball Earth'? In ponds, study suggests
Earth has not always been so hospitable to live. During several ice ages, the planet's surface was almost completely frozen over, creating what has been dubbed "Snowball Earth". Liquid water appears to be the most important ingredient for life on any planet, raising the question: how did anything survive such frosty, brutal times? A group of scientists said Thursday that they had found an astonishing diversity of micro-organisms in tiny pools of melted ice in Antarctica, suggesting that life could have ridden out Snowball Earth in similar ponds. During the Cryogenian Period between 635 and 720 million years ago, the average global temperature did not rise above -50 degrees Celsius (-58 Fahrenheit). The climate near the equator at the time resembled modern-day Antarctica. Yet even in such extreme conditions, life found a way to keep evolving. Fatima Husain, the lead author of a new study published in Nature Communications, told AFP there was evidence of complex life forms "before and after the Cryogenian in the fossil record". "There are multiple hypotheses regarding possible places life may have persisted," said Husain, a graduate student at the Massachusetts Institute of Technology. Perhaps it found shelter in patches of open ocean, or in deep-sea hydrothermal vents, or under vast sheets of ice. The tiny melted ice pools that dotted the equator were another proposed refuge. These ponds could have been oases for eukaryotes, complex organisms that eventually evolved into multicellular life forms that would rise to dominate Earth, including humans. - Could aliens be hiding in ponds? - Melted ice ponds still exist today in Antarctica, at the edges of ice sheets. In 2018, members of a New Zealand research team visited the McMurdo ice shelf in east Antarctica, home to several such pools, which are only a few metres wide and less a metre deep. The bottom of the ponds are lined with a mat of microbes that have accumulated over the years to form slimy layers. "These mats can be a few centimetres thick, colourful, and they can be very clearly layered," Husain said. They are made up of single-celled organisms called cyanobacteria that are known to be able to survive extreme conditions. But the researchers also found signs indicating there were eukaryotes such as algae or microscopic animals. This suggests there was surprising diversity in the ponds, which appears to have been influenced by the amount of salt each contained. "No two ponds were alike," Husain said. "We found diverse assemblages of eukaryotes from all the major groups in all the ponds studied." "They demonstrate that these unique environments are capable of sheltering diverse assemblages of life, even in close proximity," she added. This could have implications in the search for extraterrestrial life. "Studies of life within these special environments on Earth can help inform our understanding of potential habitable environments on icy worlds, including icy moons in our Solar System," Husain said. Saturn's moon Enceladus and Jupiter's Europa are covered in ice, but scientists increasingly suspect they could be home to simple forms of life, and several space missions have been launched to find out more about them. By Bénédicte Rey
Yahoo
a day ago
- Science
- Yahoo
How did life survive 'Snowball Earth'? In ponds, study suggests
Earth has not always been so hospitable to live. During several ice ages, the planet's surface was almost completely frozen over, creating what has been dubbed "Snowball Earth". Liquid water appears to be the most important ingredient for life on any planet, raising the question: how did anything survive such frosty, brutal times? A group of scientists said Thursday that they had found an astonishing diversity of micro-organisms in tiny pools of melted ice in Antarctica, suggesting that life could have ridden out Snowball Earth in similar ponds. During the Cryogenian Period between 635 and 720 million years ago, the average global temperature did not rise above -50 degrees Celsius (-58 Fahrenheit). The climate near the equator at the time resembled modern-day Antarctica. Yet even in such extreme conditions, life found a way to keep evolving. Fatima Husain, the lead author of a new study published in Nature Communications, told AFP there was evidence of complex life forms "before and after the Cryogenian in the fossil record". "There are multiple hypotheses regarding possible places life may have persisted," said Husain, a graduate student at the Massachusetts Institute of Technology. Perhaps it found shelter in patches of open ocean, or in deep-sea hydrothermal vents, or under vast sheets of ice. The tiny melted ice pools that dotted the equator were another proposed refuge. These ponds could have been oases for eukaryotes, complex organisms that eventually evolved into multicellular life forms that would rise to dominate Earth, including humans. - Could aliens be hiding in ponds? - Melted ice ponds still exist today in Antarctica, at the edges of ice sheets. In 2018, members of a New Zealand research team visited the McMurdo ice shelf in east Antarctica, home to several such pools, which are only a few metres wide and less a metre deep. The bottom of the ponds are lined with a mat of microbes that have accumulated over the years to form slimy layers. "These mats can be a few centimetres thick, colourful, and they can be very clearly layered," Husain said. They are made up of single-celled organisms called cyanobacteria that are known to be able to survive extreme conditions. But the researchers also found signs indicating there were eukaryotes such as algae or microscopic animals. This suggests there was surprising diversity in the ponds, which appears to have been influenced by the amount of salt each contained. "No two ponds were alike," Husain said. "We found diverse assemblages of eukaryotes from all the major groups in all the ponds studied." "They demonstrate that these unique environments are capable of sheltering diverse assemblages of life, even in close proximity," she added. This could have implications in the search for extraterrestrial life. "Studies of life within these special environments on Earth can help inform our understanding of potential habitable environments on icy worlds, including icy moons in our Solar System," Husain said. Saturn's moon Enceladus and Jupiter's Europa are covered in ice, but scientists increasingly suspect they could be home to simple forms of life, and several space missions have been launched to find out more about them. ber/dl/js
France 24
a day ago
- Science
- France 24
How did life survive 'Snowball Earth'? In ponds, study suggests
Liquid water appears to be the most important ingredient for life on any planet, raising the question: how did anything survive such frosty, brutal times? A group of scientists said Thursday that they had found an astonishing diversity of micro-organisms in tiny pools of melted ice in Antarctica, suggesting that life could have ridden out Snowball Earth in similar ponds. During the Cryogenian Period between 635 and 720 million years ago, the average global temperature did not rise above -50 degrees Celsius (-58 Fahrenheit). The climate near the equator at the time resembled modern-day Antarctica. Yet even in such extreme conditions, life found a way to keep evolving. Fatima Husain, the lead author of a new study published in Nature Communications, told AFP there was evidence of complex life forms "before and after the Cryogenian in the fossil record". "There are multiple hypotheses regarding possible places life may have persisted," said Husain, a graduate student at the Massachusetts Institute of Technology. Perhaps it found shelter in patches of open ocean, or in deep-sea hydrothermal vents, or under vast sheets of ice. The tiny melted ice pools that dotted the equator were another proposed refuge. These ponds could have been oases for eukaryotes, complex organisms that eventually evolved into multicellular life forms that would rise to dominate Earth, including humans. Could aliens be hiding in ponds? Melted ice ponds still exist today in Antarctica, at the edges of ice sheets. In 2018, members of a New Zealand research team visited the McMurdo ice shelf in east Antarctica, home to several such pools, which are only a few metres wide and less a metre deep. The bottom of the ponds are lined with a mat of microbes that have accumulated over the years to form slimy layers. "These mats can be a few centimetres thick, colourful, and they can be very clearly layered," Husain said. They are made up of single-celled organisms called cyanobacteria that are known to be able to survive extreme conditions. But the researchers also found signs indicating there were eukaryotes such as algae or microscopic animals. This suggests there was surprising diversity in the ponds, which appears to have been influenced by the amount of salt each contained. "No two ponds were alike," Husain said. "We found diverse assemblages of eukaryotes from all the major groups in all the ponds studied." "They demonstrate that these unique environments are capable of sheltering diverse assemblages of life, even in close proximity," she added. This could have implications in the search for extraterrestrial life. "Studies of life within these special environments on Earth can help inform our understanding of potential habitable environments on icy worlds, including icy moons in our Solar System," Husain said. Saturn's moon Enceladus and Jupiter's Europa are covered in ice, but scientists increasingly suspect they could be home to simple forms of life, and several space missions have been launched to find out more about them.
USA Today
28-02-2025
- Science
- USA Today
Study finds early life on Earth got a boost from ... Glaciers and uranium?
Study finds early life on Earth got a boost from ... Glaciers and uranium? Show Caption Hide Caption 'Doomsday Glacier' could be disastrous if it collapses into sea Warmed by ocean currents, Antarctica's Thwaites Glacier could collapse in a few years causing a sea levels to rise by several feet, researchers say. Scott L. Hall, USA TODAY About 700 million years ago, enormous glaciers flowed across the Earth's surface in powerful frozen rivers like "giant ice bulldozers" that pulverized our planet's crust and may have contributed to the evolution of complex life along their way, new research shows. A study published in Geology, a journal published by the Geological Society of America, on Tuesday found glaciers in rivers sometimes more than a mile deep scraped parts of the Earth's crust, releasing key minerals and setting off "chemical chain reactions that reshaped the planet," study author Chris Kirkland, who teaches and leads the Timescales of Mineral Systems Group at Curtin University in Australia, said in a statement. 'When these giant ice sheets melted, they triggered enormous floods that flushed minerals and their chemicals, including uranium, into the oceans,' Kirkland said. 'This influx of elements changed ocean chemistry, at a time when more complex life was starting to evolve.' Kirkland and researchers the University of Portsmouth in England and St. Francis Xavier University in Canada chemically analyzed crystals in rocks from Earth's Cryogenian period. Earth was so cold at the time that the oceans were frozen all the way to the equator, and life only existed in the oceans and on continental shelves, study co-author Donnelly Archibald, of St. Francis Xavier University, said in a statement. 'Our research shows that ancient glaciers did far more than shape the landscape - they triggered chemical transformations that helped set the stage for complex life," said study co-author, Rob Strachan , emeritus professor at the university. "These findings highlight the deep connections between Earth's geology, climate, and the evolution of life itself.' The planet experienced at least two "extreme global glaciations" during the Cryogenian period, traces of which can be observed in sedimentary rocks, Kirkland wrote in The Conversation. The Doomsday Glacier is melting − fast: How sea level rise could drench the world map. It's not clear what triggered those events, but high levels of carbon dioxide in the atmosphere produced by volcanic activity may have later caused the planet to warm and the ice to melt, according to Kirkland. He wrote that while many scientists believe that this caused changes in the ocean's chemistry that set the stage for the development of complex life, his new research found that the paths carved by the retreating glaciers may also have been a factor. The glaciers ground surface rock into fine sediment, which flowed rapidly into the oceans, Archibald said in a statement. 'Some of this sediment carried essential nutrients to the oceans and fundamentally changed ocean chemistry and oxygen levels in the atmosphere, which may have stimulated the evolution of multicellular life," he said. The uranium that was released into the ocean by the movement of melting glaciers, for example, boosted oxygen levels in the water, helped cycle nutrients and fueled underwater heat sources, all of which may have contributed to the early development of life, the University of Portsmouth said in a release. Kirkland said the research can not only help understand ancient climate shifts, but also modern, human-influenced climate change. "These ancient climate shifts demonstrate that environmental changes, whether natural or human-driven, have profound and lasting impacts," Kirkland said. "Understanding these past events can help us better predict how today's climate changes might reshape our world."
