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Scientists studying ice cores packing in some 60,000 years of history have found signs of thousands of volcanic eruptions across that time, stretching back to the last Ice Age – with 25 of the eruptions larger than anything Earth has seen in the last 2,500 years. Researchers excavated the cores near both poles: in Antarctica (where 737 eruptions were logged) and Greenland (where 1,113 eruptions were found). A total of 85 eruptions were large enough to leave evidence behind at both poles. That evidence takes the form of sulfuric acid deposits left behind by the eruptions. It gives researchers clues...

UNIVERSITY OF ARIZONA—The massive Toba volcanic eruption on the island of Sumatra about 74,000 years ago did not cause a six-year-long "volcanic winter" in East Africa and thereby cause the human population in the region to plummet, according to new University of Arizona-led research. The new findings disagree with the Toba catastrophe hypothesis, which says the eruption and its aftermath caused drastic, multi-year cooling and severe ecological disruption in East Africa. "This is the first research that provides direct evidence for the effects of the Toba eruption on vegetation just before and just after the eruption," said lead author Chad...

Ancient drought 'changed history' By Roland Pease BBC science unit, San Francisco The sediments are an archive of past climate conditions Scientists have identified a major climate crisis that struck Africa about 70,000 years ago and which may have changed the course of human history.The evidence comes from sediments drilled up from the beds of Lake Malawi and Tanganyika in East Africa, and from Lake Bosumtwi in Ghana. It shows equatorial Africa experienced a prolonged period of drought. It is possible, scientists say, this was the reason some of the first humans left Africa to populate the globe. Certainly,...

Highlighted by astronomers at the University of Rochester and the European Southern Observatory, the star — nicknamed “Scholz’s star” — has a very low tangential velocity in the sky, but it has been clocked traveling at a breakneck speed away from us. In other words, from our perspective, Scholz’s star is fleeing the scene of a collision with us. “Most stars this nearby show much larger tangential motion,” said Eric Mamajek, of the University of Rochester. “The small tangential motion and proximity initially indicated that the star was most likely either moving towards a future close encounter with the solar...

Focusing on mitochondrial DNA sequences from 13 Neandertal individuals, including a new sequence from the site of Valdegoba cave in northern Spain, the research team found some surprising results. When they started looking at the DNA, a clear pattern emerged. Neandertal individuals from Western Europe that were older than 50,000 years and individuals from sites in western Asia and the Middle East showed a high degree of genetic variation, on par with what might be expected from a species that had been abundant in an area for a long period of time. In fact, the amount of genetic variation was...

Indian DNA links to 6 'founding mothers' By MALCOLM RITTER, AP Science Writer NEW YORK - Nearly all of today's Native Americans in North, Central and South America can trace part of their ancestry to six women whose descendants immigrated around 20,000 years ago, a DNA study suggests. Those women left a particular DNA legacy that persists to today in about 95 percent of Native Americans, researchers said. The finding does not mean that only these six women gave rise to the migrants who crossed into North America from Asia in the initial populating of the continent, said study co-author...

"We found the very first evidence for archaeological assemblages in association with the Toba ash", says Petraglia. "We found Middle Palaeolithic assemblages below and above the ash indicating the technologies being used at the time of the event. When the stone tool assemblages were analyzed from contexts above and below the ash, we found that they were very similar........We therefore concluded that the Middle Palaeolithic hominins survived the eruption and there was population continuity. This is not what would have been expected based on general theories that the Toba super-eruption decimated populations." Moreover, similar findings published by Christine Lane, et...

This is the result of a DNA study done by Professor Stephen Oppenheimer and funded by The Bradshaw Foundation. As you go on the journey, here are some things I would like you to make note of and I would appreciate your comments:1. 135-115,000 years ago, notice that the first human excursion out of Africa failed/Died out.2. 74,000 years ago Toba exploded and reduced the worldwide human population to 2-10,000. Note the (about) 10,000 year absence of humans in India, Pakistan and parts of SE Asia. Also, there are two populations of 'out of Africa' humans that are seperated from...

...a team of archaeologists excavating in India then claimed to have found evidence that modern humans were there before the eruption possibly as early as 120,000 years ago, much earlier than Europe or the Near East were colonised. These findings, based on the discovery of stone tools below a layer of Toba ash, were published in Science in 2007. Now Professor Richards working principally with the archaeologist Professor Sir Paul Mellars, of the University of Cambridge and the University of Edinburgh, with a team including Huddersfield University s Dr Martin Carr and colleagues from York and Porto has published his...

The idea that humans nearly became extinct 75,000 ago because of a super-volcano eruption is not supported by new data from Africa, scientists say. In the past, it has been proposed that the so-called Toba event plunged the world into a volcanic winter, killing animal and plant life and squeezing our species to a few thousand individuals. An Oxford University-led team examined ancient sediments in Lake Malawi for traces of this climate catastrophe. It could find none... Researchers estimate some 2,000-3,000 cubic kilometres of rock and ash were thrown from the volcano when it blew its top on what is...

About 74,000 years ago, the Toba volcano on the Indonesian island of Sumatra erupted with catastrophic force. Estimated to be 5,000 times larger than the 1980 eruption of Mount St. Helens, it is believed to be the largest volcanic event on Earth in the last 2 million years. Toba spewed enough lava to build two Mount Everests, it produced huge clouds of ash that blocked sunlight for years, and it the left behind a crater 31 miles (50 kilometers) across. The volcano even sent enough sulphuric acid into the atmosphere to create acid rain downpours in the Earth's polar regions,...

WASHINGTON — Human beings may have had a brush with extinction 70,000 years ago, an extensive genetic study suggests. The human population at that time was reduced to small isolated groups in Africa, apparently because of drought, according to an analysis released Thursday. The report notes that a separate study by researchers at Stanford University estimated the number of early humans may have shrunk as low as 2,000 before numbers began to expand again in the early Stone Age.

Study says near extinction threatened people By RANDOLPH E. SCHMID, AP WriterApril 24,2008 (AP) -- Human beings may have had a brush with extinction 70,000 years ago, an extensive genetic study suggests. The human population at that time was reduced to small isolated groups in Africa, apparently because of drought, according to an analysis released Thursday. The report notes that a separate study by researchers at Stanford University estimated the number of early humans may have shrunk as low as 2,000 before numbers began to expand again in the early Stone Age. "This study illustrates the extraordinary power of genetics...

Researchers at Rensselaer Polytechnic Institute have discovered what likely triggered the eruption of a "supervolcano" that coated much of the western half of the United States with ash fallout 760,000 years ago. Using a new technique developed at Rensselaer, the team determined that there was a massive injection of hot magma underneath the surface of what is now the Long Valley Caldera in California some time within 100 years of the gigantic volcano’s eruption. The findings suggest that this introduction of hot melt led to the immense eruption that formed one of the world’s largest volcanic craters or calderas. The...

Chinese challenge to 'out of Africa' theory 00:01 03 November 2009 by Phil McKenna The discovery of an early human fossil in southern China may challenge the commonly held idea that modern humans originated out of Africa. Jin Changzhu and colleagues of the Institute of Vertebrate Palaeontology and Palaeoanthropology in Beijing, announced to Chinese media last week that they have uncovered a 110,000-year-old putative Homo sapiens jawbone from a cave in southern China's Guangxi province.

Eruption May Have Been Bigger Larry O'Hanlon, Discovery News Dec. 21, 2006 — One of the largest volcanic eruptions on record just got bigger. The Taupo Volcanic Zone of New Zealand appears to have had twin eruptions only 20 miles apart within days of each other a quarter-million years ago. Each eruption belched out more than 25 cubic miles (100 cubic kilometers) of rock and volcanic ash. This is the first evidence of twin supervolcanic eruptions. "It's possible one of these triggered the other," said geologist Darren Gravley of the University of Auckland, New Zealand. But exactly how the...

Are you worried about the end of life as we know it? Then don't just look to the sky for that catastrophic asteroid that could be heading our way. The end may come from right beneath your feet. Super-volcanoes have probably caused more extinctions than asteroids. But until now it has been thought that these giant volcanoes took thousands of years to form -- and would remain trapped beneath the earth's crust for thousands more years -- before having much effect on the planet. But new research indicates these catastrophic eruptions, possibly thousands of times more powerful than the 1980...

Ice cores unlock climate secrets By Julianna Kettlewell BBC News Online science staff Tiny bubbles of ancient air are locked in the ice Global climate patterns stretching back 740,000 years have been confirmed by a three kilometre long ice core drilled from the Antarctic, Nature reports. Analysis of the ice proves our planet has had eight Ice Ages during that period, punctuated by rather brief warm spells - one of which we enjoy today. If past patterns are followed in the future, we can expect our "mild snap" to last another 15,000 years. The data may also help predict how...

"Super volcano" could dwarf Indonesia's earthquake catastrophes: expert Fri Apr 1,12:21 AM ET Science - AFP SYDNEY (AFP) - As Indonesians struggled to recover from the second deadly earthquake to strike them in three months, an Australian expert warned the country faced the prospect of a "super volcano" eruption that would dwarf all previous catastrophes. AFP/File Photo Professor Ray Cas of Monash University's School of Geosciences said the world's biggest super volcano was Lake Toba, on Indonesia's island of Sumatra, site of both the recent massive earthquakes. Cas told Australian media Friday that Toba sits on a faultline running down...

Newly discovered archaeological sites in southern and northern India have revealed how people lived before and after the colossal Toba volcanic eruption 74,000 years ago... The seven-year project examines the environment that humans lived in, their stone tools, as well as the plants and animal bones of the time. The team has concluded that many forms of life survived the super-eruption, contrary to other research which has suggested significant animal extinctions and genetic bottlenecks. According to the team, a potentially ground-breaking implication of the new work is that the species responsible for making the stone tools in India was Homo...