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Categories: Paleontology: Climate, Paleontology: Early Mammals and Birds

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The San Joaquin Valley in California has experienced vast variability in climate extremes, with droughts and floods that were more severe and lasted longer than what has been seen in the modern record, according to a new study of 600 years of tree rings from the valley.

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A landmark study into the geological timescale distribution of sediment and nutrients over 500 million years shows that species biodiversity on Earth is driven by landscape dynamics.

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Scientists have made a surprising discovery that sheds new light on the role that oceanic deoxygenation (anoxia) played in one of the most devastating extinction events in Earth's history. Their finding has implications for current day ecosystems -- and serves as a warning that marine environments are likely more fragile than apparent. New research, published today in leading international journal Nature Geosciences, suggests that oceanic anoxia played an important role in ecosystem disruption and extinctions in marine environments during the Triassic--Jurassic mass extinction, a major extinction event that occurred around 200 million years ago.  Surprisingly however, the study shows that the global extent of euxinia (an extreme form of de-oxygenated conditions) was similar to the present day.

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Modern hippos first dispersed in Europe during the Middle Pleistocene, according to a new study.

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Using historical records from around Australia, an international team of researchers have put forward the most accurate prediction to date of past Antarctic ice sheet melt, providing a more realistic forecast of future sea level rise.   The Antarctic ice sheet is the largest block of ice on earth, containing over 30 million cubic kilometers of water.   Hence, its melting could have a devasting impact on future sea levels. To find out just how big that impact might be, the research team turned to the past.  

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Australia's only vulture, and a fearsome extinct eagle, are among the earliest recorded birds of prey from the Pleistocene period more than 50,000 years ago -- and now researchers are bringing them to 'life' again.    Along with new scientific information, a bold new pictorial reconstruction of a newly named eagle and the only known Australian vulture will be unveiled at the World Heritage-listed Naracoorte Caves in South Australia's Limestone Coast this month.  

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The discovery of 27 avian footprints on the southern Australia coast -- dating back to the Early Cretaceous when Australia was still connected to Antarctica -- opens another window onto early avian evolution and possible migratory behavior.

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Ancient cycad lineages that survived the extinction of the dinosaurs may have done so by relying on symbiotic bacteria in their roots to fix atmospheric nitrogen. The finding came from an effort to understand ancient atmospheres, but became an insight into plant evolution instead.

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Past cold periods such as the Little Ice Age were associated with reduced strength of North Atlantic currents and increased surface salinity in the Caribbean. This was accompanied by disturbances in the distribution of salt to the north leading to longer, stronger cooling phases in the northern hemisphere.

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During the last ice age, the last glacial maximum about 20,000 years ago, the climate in the North Atlantic underwent much greater multi-centennial variability than it does in the present warm period. This is supported by evidence found in ice and seafloor cores. Researchers have now shown, based on a climate model, that internal mechanisms such as temperature and salinity distribution in the ocean are driving this multi-centennial variability.

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A new study takes an important step toward reconstructing a global history of water over the past 2,000 years. Using geologic and biologic evidence preserved in natural archives -- including 759 different paleoclimate records from globally distributed corals, trees, ice, cave formations and sediments -- the researchers showed that the global water cycle has changed during periods of higher and lower temperatures in the recent past.

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Researchers have mapped how land use changed across Britain throughout the last century. The new map reveals how and where some 50 per cent of semi-natural grassland was lost, including 90 per cent of the country's lowland meadows and pasture, as the nation intensified its agriculture.

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A new Antarctic ice sheet modeling study suggests that meltwater flowing out to sea from beneath Antarctic glaciers is making them lose ice faster.   

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The explosion of the underwater volcano Kolumbo in the Aegean Sea in 1650 triggered a destructive tsunami that was described by historical eye witnesses. A group of researchers has now surveyed Kolumbo's underwater crater with modern imaging technology and reconstructed the historical events. They found that the eyewitness accounts of the natural disaster can only be described by a combination of a landslide followed by an explosive eruption.

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Human populations in Neolithic Europe fluctuated with changing climates, according to a new study.

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Scientists analyzed open-source data to track vegetation changes across North America since the end of the Pleistocene Epoch, and conclude that humans have had as much of an impact on the landscape as the retreat of the glaciers at the end of the Ice Age. 

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A team has identified several factors to help answer a fundamental ecological question: why is there a ridiculous abundance of species some places on earth and a scarcity in others? What factors, exactly, drive animal diversity? They discovered that what an animal eats (and how that interacts with climate) shapes Earth's diversity.

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Meltwater that runs along the east coast of Greenland, hardly enters the open ocean before reaching the western side of the island.  In the changing climate, fresh water from Greenland and the Arctic could disrupt the circulation in the Atlantic Ocean.

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Bats may have lived in caves and used soundwaves to navigate much earlier than first thought.

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New research by climate scientists indicates that there have been great changes to Atlantic hurricanes in just the past 50 years, with storms developing and strengthening faster.