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Researchers from the Leibniz Institute for Baltic Sea Research in Warnemünde report the discovery of an ancient, 10,000-year-old massive stone wall that has remained submerged beneath the Baltic Sea for millennia.At nearly a kilometer in length, the Stone Age megastructure hidden beneath the waters of the Bay of Mecklenburg in Germany is not only one of the oldest man-made hunting structures in Europe but likely one of the oldest pieces of construction in the entire world."It was likely constructed by hunter–gatherer groups more than 10000 y ago and ultimately drowned during the Littorina transgression at 8500 y B.P.," the researchers...

The discovery of a young adult who lived for years with an amputated leg pushes back the first documented limb surgery by 20,000 years.At the beginning of the last Ice Age, 31,000 years ago, a community in what’s now Eastern Indonesia buried a young person in the dry floor of a mountainside cave painted with handprints. The people lived on the edge of what was then a low continent called Sunda, and they were likely part of the same group of early seafarers who crossed to Australia. They were sophisticated in other ways, too: According to a description of the...

...the journal The Anatomical Record has published a study coordinated by Emiliano Bruner, who leads the Paleoneurology Group at the Centro Nacional de Investigación sobre la Evolución Humana (CENIEH), that analyzes the distribution of certain craniovascular traits in four native populations from the late Holocene in the southernmost regions of South America.The sample includes 70 skulls, dated to between 200 and 3,000 years old, from populations of four regions in Argentina: the pampas (Buenos Aires), southern Andes (Salta), central Patagonia (Chubut), and southern Patagonia (Tierra del Fuego). The four groups do not present substantial differences although, as has been observed...

When and why did human brains decrease in size 3,000 years ago? New study may have found clues within ants. =========================================================================== The brain is the most complex organ in the human body. Now, a new study has brought us closer to understanding some of its evolution. It shows that human brains decreased in size approximately 3,000 years ago. By studying ants as models to illustrate why brains may increase or decrease in size, the researchers hypothesize that brain shrinkage parallels the expansion of collective intelligence in human societies. Studying and understanding the causes and consequences of brain evolution helps us...

Double impact may have caused tsunami, global cooling Pieces of a giant asteroid or comet that broke apart over Earth may have crashed off Australia about 1,500 years ago, says a scientist who has found evidence of the possible impact craters. Satellite measurements of the Gulf of Carpentaria (see map) revealed tiny changes in sea level that are signs of impact craters on the seabed below, according to new research by marine geophysicist Dallas Abbott. Based on the satellite data, one crater should be about 11 miles (18 kilometers) wide, while the other should be 7.4 miles (12 kilometers) wide....

A series of tracks created roughly 14,000 years ago has revealed stunning new insight into the ways ancient humans explored dark, potentially treacherous cave systems during the Stone Age. Researchers say at least 180 hand and footprints line the clay-rich floor of Italy’s cave of Bàsura in the famous Toirano caves, indicating ancient humans crawled barelegged through low tunnels as they searched for food and even explored for fun. The group that left behind these tracks thousands of years ago included a total of five individuals, from adults to children as young as 3 years old, who navigated the dark...

Following the discovery of the 19.2-mile wide Hiawatha impact crater beneath the northwest margin of the Greenland Ice Sheet, Dr. Joe MacGregor of NASA’s Goddard Space Flight Center and colleagues explored satellite and aerogeophysical data in search of additional such craters and found a possible second impact crater that is 22.7 miles wide and 114 miles southeast of the Hiawatha crater. The discovery is described in a paper in the journal Geophysical Research Letters. ..." Following the finding of that first crater, Dr. MacGregor and co-authors checked topographic maps of the rock beneath Greenland’s ice for signs of other craters....

An international team of geoscientists from the United States, Canada and Europe has discovered a large impact crater beneath the Hiawatha Glacier in remote northwest Greenland. A paper on the discovery was published in the journal Science Advances. The Hiawatha impact crater is approximately 19.2 miles (31 km) wide and lies under an ice sheet that is 0.6 miles (1 km) thick.The scientists believe this crater was formed by a 0.6-mile wide iron asteroid that slammed into the Earth at the end of the Pleistocene epoch, perhaps as recently as 12,000 years ago. ..." “Researchers were looking at the map...

On a bright July day 2 years ago, Kurt Kjær was in a helicopter flying over northwest Greenland—an expanse of ice, sheer white and sparkling. Soon, his target came into view: Hiawatha Glacier, a slow-moving sheet of ice more than a kilometer thick. It advances on the Arctic Ocean not in a straight wall, but in a conspicuous semicircle, as though spilling out of a basin. Kjær, a geologist at the Natural History Museum of Denmark in Copenhagen, suspected the glacier was hiding an explosive secret. The helicopter landed near the surging river that drains the glacier, sweeping out rocks...

It's like the underside of the island got a good roasting in the distant past and still has the big scar to prove it. That hotspot, by the way, is the one which today is building Iceland in the middle of the North Atlantic. The plume of broiling rock rising from deep inside the Earth has broken through the thin ocean floor at Iceland's location and is now creating new land with regular eruptions of lava. Greenland's warm NW-SE band is reported by a team of researchers led by the US space agency (Nasa) and the British Antarctic Survey (BAS)....

A meteor hit Earth and exploded with 2.1 kilotons of force in July, but the Air Force has made no mention of the event. NASA’s Jet Propulsion Laboratory confirmed an object of unspecified size traveling at 15.1 miles per second (54,360 miles per hour) struck the ground in Greenland, just 27 miles north of Thule Air Base, on July 25. The base is mainly used to detect missile launches. Director of the Nuclear Information Project for the Federation of American Scientists Hans Kristensen tweeted about the impact, but the US Air Force has not reported the event. Kristensen argues it’s...

The Air Force said Friday that there was no damage to Thule Air Base in Greenland after a large meteor fell nearby last week. The fireball incident occurred just miles from the remote military base on July 25 and entered the atmosphere with a 2.1 kiloton force, according to the NASA Jet Propulsion Laboratory. The atomic bomb dropped on Hiroshima was 15 kilotons. The Air Force 21st Space Wing monitors missile launches and space activity via sensors at Thule, and directed any questions to NASA, which did not immediately provide a statement.

A meteor hit the earth and exploded with 2.1 kilotons of force last month, but the US Air Force has made no mention of the event. NASA’s Jet Propulsion Laboratory confirmed an object of unspecified size travelling at 24.4 kilometres per second struck earth in Greenland, just 43 kilometres north of an early missile warning Thule Air Base on the 25th of July, 2018. Director of the Nuclear Information Project for the Federation of American Scientists, Hans Kristensen, tweeted about the impact, but America’s Air Force has not reported the event.Mr. Kristensen argues it’s concerning there was no public warning...

Around 13,000 years ago, the Earth burned. A swarm of comet debris from the Taurid meteor stream had blasted the Americas and parts of Europe; the worst day in prehistory since the end of the ice age. Many species of large animal were exterminated by the conflagration and ensuing cataclysms. And those that survived the initial onslaught could do little against the floods, acid rain, and starvation that followed.

The Younger Dryas impact hypothesis, also known as Clovis comet hypothesis, posits that the hemisphere-wide debris field of a large, disintegrating asteroid (or comet) struck North America, South America, Europe, and western Asia approximately 12,800 years ago. This event triggered extensive biomass burning, brief impact winter, climate change, and contributed to extinctions of late Pleistocene megafauna. Controversial from the time it was proposed, this hypothesis continues to be contested by those who prefer to attribute the end-Pleistocene reversal in (global) warming entirely to terrestrial causes. Now, University of California, Santa Barbara’s Professor James Kennett and co-authors present further geologic and...

When UC Santa Barbara geology professor emeritus James Kennett and colleagues set out years ago to examine signs of a major cosmic impact that occurred toward the end of the Pleistocene epoch, little did they know just how far-reaching the projected climatic effect would be... the Younger Dryas Impact Hypothesis, which postulates that a fragmented comet slammed into the Earth close to 12,800 years ago, causing rapid climatic changes, megafaunal extinctions, sudden human population decrease and cultural shifts and widespread wildfires (biomass burning)... suggests a possible triggering mechanism for the abrupt changes in climate at that time, in particular a...

“We think we may have found the answer. Increased circulation in the Southern Ocean allowed carbon dioxide to leak into the atmosphere, working to warm the planet,” said Princeton University’s Professor Daniel Sigman, co-author of the study. For years, researchers have known that growth and sinking of phytoplankton pumps carbon dioxide deep into the ocean, a process often referred to as the ‘biological pump.’ “The biological pump is driven mostly by the low latitude ocean but is undone closer to the poles, where carbon dioxide is vented back to the atmosphere by the rapid exposure of deep waters to the...

The Meghalayan...runs from 4,200 years ago to the present. It began with a destructive drought, whose effects lasted two centuries, and severely disrupted civilisations in Egypt, Greece, Syria, Palestine, Mesopotamia, the Indus Valley, and the Yangtze River Valley. The Meghalayan Age is unique among the many intervals of the geologic timescale in that its beginning coincides with a global cultural event produced by a global climatic event... The middle phase of the Holocene will be referred to as the Northgrippian, and runs from 8,300 years ago up to the start of the Meghalayan. The onset for this age was an...

Although researchers have long known that the last two interglacial periods experienced warming in the Arctic... Just beyond the northwest edge of the vast Greenland Ice Sheet, Northwestern University researchers have discovered lake mud that beat tough odds by surviving the last ice age. The mud, and remains of common flies nestled within it, record two interglacial periods in northwest Greenland. Although researchers have long known these two periods -- the early Holocene and Last Interglacial -- experienced warming in the Arctic due to changes in Earth's orbit, the mix of fly species preserved from these times shows that Greenland...

Seafaring before the Neolithic -- circa 7th millennium BCE -- is a controversial issue in the Mediterranean. However, evidence from different parts of the Aegean is gradually changing this, revealing the importance of early coastal and island environments. The site of Ouriakos on the island of Lemnos (Greece) tentatively dates to the end of the Pleistocene and possibly the beginning of the Holocene, circa 12,000 BP... Obsidian, or 'volcanic glass', has been a preferred material for stone tools wherever it is found or traded. It also absorbs water vapour when exposed to air -- for instance, when it is shaped...