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Categories: Anthropology: Early Humans, Paleontology: Climate
Published Mercury helps to detail Earth's most massive extinction event
(via sciencedaily.com) Scientists are working to understand the cause and how the events of the LPME unfolded by focusing on mercury from Siberian volcanoes that ended up in sediments in Australia and South Africa.
Published Kill dates for re-exposed black mosses
(via sciencedaily.com) Scientists have used radiocarbon ages (kill dates) of previously ice-entombed dead black mosses to reveal that glaciers advanced during three distinct phases in the northern Antarctic Peninsula over the past 1,500 years.
Published What crocodile DNA reveals about the Ice Age
(via sciencedaily.com) What drives crocodile evolution? Is climate a major factor or changes in sea levels? Determined to find answers to these questions, researchers discovered that while changing temperatures and rainfall had little impact on the crocodiles' gene flow over the past three million years, changes to sea levels during the Ice Age had a different effect.
Published Malformed seashells, ancient sediment provide clues about Earth's past
(via sciencedaily.com) Shrunken seashells and unusually dark sediment cores have helped geoscientists better understand the chronology and character of events that led to Ocean Anoxic Event 2, nearly 100 million years ago.
Published Plague trackers: Researchers cover thousands of years in a quest to understand the elusive origins of the Black Death
(via sciencedaily.com) Seeking to better understand more about the origins and movement of bubonic plague, in ancient and contemporary times, researchers have completed a painstaking granular examination of hundreds of modern and ancient genome sequences, creating the largest analysis of its kind.
Published In the Neanderthal site of Combe-Grenal, France, hunting strategies were unaffected by changing climate
(via sciencedaily.com) Neanderthals in Combe-Grenal (France) preferred to hunt in open environments, and their hunting strategies did not alter during periods of climatic change, according to a new study.
Published Global warming reaches central Greenland
(via sciencedaily.com) A temperature reconstruction from ice cores of the past 1,000 years reveals that today's warming in central-north Greenland is surprisingly pronounced. The most recent decade surveyed in a study, the years 2001 to 2011, was the warmest in the past 1,000 years, and the region is now 1.5 °C warmer than during the 20th century, as researchers report. Using a set of ice cores unprecedented in length and quality, they reconstructed past temperatures in central-north Greenland and melting rates of the ice sheet.
Published Study offers most detailed glimpse yet of planet's last 11,000 summers and winters
(via sciencedaily.com) An international team of collaborators have revealed the most detailed look yet at the planet's recent climactic history, including summer and winter temperatures dating back 11,000 years to the beginning of what is known as the Holocene.
Published Ethical ancient DNA research must involve descendant communities, say researchers
(via sciencedaily.com) The analysis of ancient DNA allows scientists to trace human evolution and make important discoveries about modern populations. The data revealed by ancient DNA sampling can be valuable, but the human remains that carry this ancient DNA are often those of the ancestors of modern Indigenous groups, and some communities have expressed concerns about the ethics of sampling by outside parties. A group of scientists make the case for involvement of descendant communities in all aspects of the research process.
Published Rodent extinctions in Hispaniola may have been caused by humans
(via sciencedaily.com) Hispaniola once had among the highest diversity of rodents in the Caribbean. Today, only one rodent species remains, and its prospects for survival are uncertain. New carbon dates place the blame squarely on humans.
Published Smallpox has plagued humans since ancient Egyptian times, new evidence confirms
(via sciencedaily.com) Original source Smallpox was once one of humanity's most devastating diseases, but its origin is shrouded in mystery. For years, scientific estimates of when the smallpox virus first emerged have been at odds with historical records. Now, a new study reveals that the virus dates back 2,000 years further than scientists have previously shown, verifying historical sources and confirming for the first time that the disease has plagued human societies since ancient times.
Published Study reveals average age at conception for men versus women over past 250,000 years
(via sciencedaily.com) Using a new method based upon comparing DNA mutation rates between parents and offspring, evolutionary biologists have revealed the average age of mothers versus fathers over the past 250,000 years, including the discovery that the age gap is shrinking, with women's average age at conception increasing from 23.2 years to 26.4 years, on average, in the past 5,000 years.
Published Climate change could cause 'disaster' in the world's oceans
(via sciencedaily.com) Original source Climate change will slow down deep overturning ocean circulation in the coming centuries. Using three dozen Earth system models, researchers have concluded that the Southern Meridional Overturning Circulation could completely shut down by 2300, causing disaster to the marine ecosystem on a large portion of the planet.
Published Bering Land Bridge formed surprisingly late during last ice age
(via sciencedaily.com) A new study that reconstructs the history of sea level at the Bering Strait shows that the Bering Land Bridge connecting Asia to North America did not emerge until around 35,700 years ago, less than 10,000 years before the height of the last ice age (known as the Last Glacial Maximum). The findings indicate that the growth of the ice sheets -- and the resulting drop in sea level -- occurred surprisingly quickly and much later in the glacial cycle than previous studies had suggested.
Published Archaeologists uncover oldest known projectile points in the Americas
(via sciencedaily.com) Archaeologists have uncovered projectile points in Idaho that are thousands of years older than any previously found in the Americas, helping to fill in the history of how early humans crafted and used stone weapons.
Published Early forests did not significantly change the atmospheric CO2
(via sciencedaily.com) Original source Scientists have discovered that the atmosphere contained far less CO2 than previously thought when forests emerged on our planet, the new study has important implications for understanding how land plants affect the climate.
Published New theory on timing for human settlement of some parts of tropical Pacific
(via sciencedaily.com) Spread across vast distances, the islands of the tropical Pacific Ocean are thought to have been populated by humans in two distinct migrations beginning approximately 3,330 years ago. The first followed a northern route out of what is today the Philippines and the second followed a southern route from Taiwan and New Guinea. People arrived on the islands between these routes -- now making up the Federated States of Micronesia -- about 1,000 years later. But a new finding by sea-level researchers suggests that the islands in Micronesia were possibly settled much earlier than supposed and that voyagers on the two routes may have interacted with one another.
Published Linking fossil climate proxies to living bacteria helps climate predictions
(via sciencedaily.com) Fossilized microbial skins can give us a glimpse of how the climate was in the deep geological past. By discovering the 'missing link' between such fossil skins and the skins of living bacteria, researchers have greatly improved the accuracy of climate reconstructions and predictions.
Published Climate change played key role in dinosaur success story
(via sciencedaily.com) Climate change, rather than competition, played a key role in the ascendancy of dinosaurs through the Late Triassic and Early Jurassic periods.
Published Early humans may have first walked upright in the trees
(via sciencedaily.com) Human bipedalism -- walking upright on two legs -- may have evolved in trees, and not on the ground as previously thought, according to a new study.