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Categories: Anthropology: Early Humans, Ecology: Nature

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Researchers investigated how the jaw shape of sharks has changed over the course of evolution. Their conclusion: in the most widespread shark species, the jaws show relatively little variation in shape over millions of years; most variable jaws were found for deep-sea sharks.

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Up to two-thirds of the soot above the central Amazon rainforest originates in Africa. Researchers differentiate soot particles using their relative properties and attribute them to their respective points of origin. They found that bush fires and burning savannah in the north and south of Africa make a substantial contribution to air pollution in the central Amazon all year round, thereby playing an important role in the earth radiation budget and water cycle. This is caused by the efficient transatlantic transport of particles through the atmosphere.

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Deforestation is the biggest threat to the planet's ecosystems, and new research has now mapped out exactly what happens when agriculture replaces forestry.

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Scientists have discovered where butterflies originated and which plants the first butterflies relied on for food. To reach these conclusions, researchers created the world's largest butterfly tree of life, which they used as a guide to trace trace the evolution of butterflies through time in a four-dimensional puzzle that led back to North and Central America.

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Scientists have precisely identified base pairs of the human genome that remained consistent over millions of years of mammalian evolution, and which play a crucial role in human disease. The team analyzed the genomes of 240 mammals, including humans and identified base pairs that were 'constrained' -- meaning they remained generally consistent -- across mammal species over the course of evolution. The most constrained base pairs in mammals were over seven times more likely to be causal for human disease and complex trait, and over 11 times more likely when researchers looked at the most constrained base pairs in primates alone.

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Throughout the ocean, billions upon billions of plant-like microbes make up an invisible floating forest. As they drift, the tiny organisms use sunlight to suck up carbon dioxide from the atmosphere. Collectively, these photosynthesizing plankton, or phytoplankton, absorb almost as much CO2 as the world’s terrestrial forests. A measurable fraction of their carbon-capturing muscle comes from Prochlorococcus — an emerald-tinged free-floater that is the most abundant phytoplankton in the oceans today. New research suggests the microbe's ancient coastal ancestors colonized the ocean by rafting out on chitin particles.

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A new study finds that early human species adapted to mosaic landscapes and diverse food resources, which would have increased our ancestor's resilience to past shifts in climate.

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Scalloped hammerhead sharks hold their breath to keep their bodies warm during deep dives into cold water where they hunt prey such as deep sea squids. This discovery provides important new insights into the physiology and ecology of a species that serves as an important link between the deep and shallow water habitats.

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Boreal wetlands are a significant source of isoprene and terpenes, a class of highly reactive organic compounds that have a substantial impact on the Earth's climate, according to a new study.

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Surveying the body sizes of Earth's living organisms, researchers found that the planet's biomass -- the material that makes up all living organisms -- is concentrated in organisms at either end of the size spectrum.

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The theory that water-breathing animals such as fish will shrink due to global warming has been called into question by a new study.

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Which energy type promotes the biodiversity of beetles living in dead wood in the forest? That depends entirely on where the beetles are in the food chain.

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Fungal networks interconnecting trees in a forest is a key factor that determines the nature of forests and their response to climate change. These networks have also been viewed as a means for trees to help their offspring and other tree-friends, according to the increasingly popular 'mother-tree hypothesis'. An international group of researchers re-examined the evidence for and against this hypothesis in a new study.

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Small-scale wildlife surveys can reveal the health of entire ecosystems, new research shows.

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Scientists have used mitochondrial DNA to trace a female lineage from northern coastal China to the Americas. By integrating contemporary and ancient mitochondrial DNA, the team found evidence of at least two migrations: one during the last ice age, and one during the subsequent melting period. Around the same time as the second migration, another branch of the same lineage migrated to Japan, which could explain Paleolithic archeological similarities between the Americas, China, and Japan.

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The roles microbes play in ecosystems are changing with global warming. Microbes are also affected by infection by viruses, but scientists know relatively little about how these viral infections could change how microbes react to warming. In this study, scientists describe different ways that increasing temperatures could affect viruses and their microbial hosts. Their preliminary models show that viruses could alter carbon balance, causing some ecosystems to switch from net carbon sources to net carbon sinks.

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Birds across the Americas are getting smaller and longer-winged as the world warms, and the smallest-bodied species are changing the fastest.

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Humans inherited genetic material from Neanderthals that affects the shape of our noses, finds a new study.

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Using a long-term multifactor experimental field site researchers showed that experimental warming of a tallgrass prairie ecosystem significantly altered the community structure of soil archaea and reduced their taxonomic and phylogenetic diversity.

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For decades, scientists have used the amount of seaweed at the ocean's surface as a proxy for the health of coral reefs below. However, a new global study of more than 1,200 marine locations over a 16-year period reveals that this approach has been misleading -- and may even have hidden signs of reef stress.