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Categories: Ecology: Trees, Paleontology: Climate

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Sediment cores obtained from Eifel maar sites provide insight into the presence of large Ice Age mammals in Central Europe over the past 60,000 years: Overkill hypothesis not confirmed. Herds of megafauna, such as mammoth and bison, have roamed the prehistoric plains in what is today's Central Europe for several tens of thousands of years. As woodland expanded at the end of the last Ice Age, the numbers of these animals declined and by roughly 11,000 years ago, they had completely vanished from this region. Thus, the growth of forests was the main factor that determined the extinction of such megafauna in Central Europe.

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Changes in Earth's orbit that favored hotter conditions may have helped trigger a rapid global warming event 56 million years ago. Researchers found the shape of Earth's orbit, or eccentricity, and the wobble in its rotation, or precession, favored hotter conditions at the onset of the PETM and that these orbital configurations together may have played a role in triggering the event.

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Short-term, heavy feeding by adult spotted lanternflies on young maple trees inhibits photosynthesis, potentially impairing the tree's growth by up to 50 percent, according to a new study.

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By assessing so-called 'flavors' of El Nino events in past climate records and model simulations, researchers have a clearer picture of El Nino patterns over the past 12,000 years and are able to more accurately project future changes and impacts of this powerful force.

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New research findings could help scientists control the emerald ash borer, an invasive pest ravaging native ash trees in North America.

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Researchers have been studying the effects of the sudden decrease in global temperatures that occurred about 8,200 years ago, the so-called 8.2-kiloyear event, with the help of mineral deposits present in White Moon Cave in Northern California. New indications show that oscillations between extreme wetness and aridity in California were closely linked with the occurrence of wildfires. The researchers have concluded that such events are likely to become more common in the face of human-induced climate change.

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How is the weather changing as a consequence of global warming? Climate archives provide valuable glimpses into past climate changes, especially into the processes that drive our planet from one climate setting to the next. For humans and ecosystems, however, time spans of just weeks to years, which are the scope of weather events, are often most important. Using an newly developed and tested analytical method these two aspects have now been merged, and the impacts of the most recent global warming on seasonal temperature fluctuations have been described.

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Two-million-year-old DNA has been identified -- opening a 'game-changing' new chapter in the history of evolution. Microscopic fragments of environmental DNA were found in Ice Age sediment in northern Greenland. Using cutting-edge technology, researchers discovered the fragments are one million years older than the previous record for DNA sampled from a Siberian mammoth bone. The ancient DNA has been used to map a two-million-year-old ecosystem which weathered extreme climate change.

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There's a new branch on the tree of life and it's made up of predators that nibble their prey to death. These microbial predators fall into two groups, one of which researchers have dubbed 'nibblerids' because they, well, nibble chunks off their prey using tooth-like structures. The other group, nebulids, eat their prey whole. And both comprise a new ancient branch on the tree of life called 'Provora,' according to a new article.

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The ability of tropical forests to grow and store carbon is limited, in part, by herbivory. Insects and other animals prefer to feed on nitrogen-fixing trees, reducing the success of fixers and the nitrogen they provide. Experts now recommend accounting for herbivory constraints on nitrogen-fixing trees in climate models and projections of the tropical forest carbon sink.

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A chance find of an unstudied Antarctic sediment core has led researchers to flip our understanding of how often ice ages occurred in Antarctica.

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A forest's resilience, or ability to absorb environmental disturbances, has long been thought to be a boost for its odds of survival against the looming threat of climate change. But a new study suggests that for some Western U.S. forests, it's quite the opposite. The results of one of the first large-scale studies of its kind show that while high ecosystem resilience correlates with low mortality in eastern forests, it is linked to high mortality in western regions.

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The Southern Hemisphere is stormier than the Northern -- but no one knew why. A new study lays out the first concrete explanation for this phenomenon. Researchers found two major culprits: ocean circulation and the large mountain ranges in the Northern Hemisphere.

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More and more trees are suffering the consequences of decades of human-made climate change. The growth of the European beech has so far suffered decline mainly in southern Europe. European beech is Germany's most important native forest tree species and it is most commonly found in Central Europe. A research team has now been able to show that the European beech is suffering from increasing drought stress in summer in northern Germany as well. This climate stress is particularly pronounced at warmer sites, when there is a higher density of these trees together, and on very sandy soils.

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Major ice streams can shut down, shifting rapid ice transport to other parts of the ice sheet, within a few thousand years. This was determined in reconstructions of two ice streams, based on ice-penetrating radar scans of the Greenland ice sheet.

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A new study has evaluated the relationship between better mental health and the 3-30-300 green space rule. According to this rule of thumb, everyone should be able to see at least three trees from their home, have 30 percent tree canopy cover in their neighborhood and not live more than 300 meters away from the nearest park or green space.

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Years of research show that climate change signals are amplified in the Arctic, and that sea ice in this region is sensitive to increases in Arctic warming. Sea ice greatly modifies the exchanges of heat, momentum and mass between the atmosphere and the ocean. So, the timings of the sea ice melt and freeze onsets, as well as the length of the melt and freeze seasons, play a key role in the 'heat budget' of the atmosphere-ice-ocean system.

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Marking trees are important hotspots of communication for cheetahs: Here they exchange information with and about other cheetahs via scent marks, urine and scats. A team has now shown that several mammalian species on farmland in Namibia maintain a network for intra- and interspecific communication at cheetah trees. Black-backed jackals, African wildcats and warthogs visited and sniffed the cheetahs' 'places to be' more frequently than control trees, the team concluded from photos and videos recorded by wildlife camera traps. A common prey species of the cheetahs, however, avoided these hotspots.

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A new analysis of more than 20,000 trees on five continents shows that old-growth trees are more drought tolerant than younger trees in the forest canopy and may be better able to withstand future climate extremes. The findings highlight the importance of preserving the world's remaining old-growth forests, which are biodiversity strongholds that store vast amounts of planet-warming carbon, according to forest ecologists.

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Paleontologists say environmental DNA is not always helpful in identifying when animals like mammoths went extinct because genetic material found in sediment could have come from animals that died thousands of years earlier.