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Categories: Anthropology: Early Humans, Ecology: Sea Life

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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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One of the basic and crucial embryonic processes to unfold in virtually every living organism is the formation of hollow, tubular structures that go on to form blood vessels or a digestive tract, and through branching and differentiation, complex organs including the heart and kidneys. This study illuminates fundamental design principles of tubulogenesis for all chordates, including mammals.

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Even without body parts that allowed for movement, new research shows -- for the first time -- that some of Earth's earliest animals managed to be picky about where they lived.

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

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Phytosterols are good for your health, but humans and other animals are not able to make them themselves, only plants can. To acquire phytosterols, humans are increasingly turning to supplements, green smoothies, or a Mediterranean diet with plenty of plant-based foods. Researchers have now discovered that tiny gutless worms from the Mediterranean can synthesize phytosterols on their own. Their study provides evidence that many other animals also have the genes needed to make their own phytosterols.

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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.

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An international research team has for the first time successfully isolated ancient human DNA from a Paleolithic artefact: a pierced deer tooth discovered in Denisova Cave in southern Siberia. To preserve the integrity of the artefact, they developed a new, nondestructive method for isolating DNA from ancient bones and teeth. From the DNA retrieved they were able to reconstruct a precise genetic profile of the woman who used or wore the pendant, as well as of the deer from which the tooth was taken. Genetic dates obtained for the DNA from both the woman and the deer show that the pendant was made between 19,000 and 25,000 years ago. The tooth remains fully intact after analysis, providing testimony to a new era in ancient DNA research, in which it may become possible to directly identify the users of ornaments and tools produced in the deep past.

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In the face of global warming and other environmental changes, corals in the Atlantic Ocean have declined precipitously in recent years, while corals in the Pacific and Indian Oceans are faring better. By describing several species of symbiotic algae that these corals need to grow, an international team has found that these mutualistic relationships from the Indo-Pacific may be more flexible and ultimately resilient to higher ocean temperatures than those in the Atlantic.

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Researchers have proposed a new evolutionary model for the origin of a kingdom of viruses called Bamfordvirae, suggesting a billion-years evolutionary arms race between two groups within this kingdom and their hosts.

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Greenlandic ice is teeming with life, both on the surface and underneath. There are microscopic organisms that until recently science had no idea existed. There is even evidence to suggest that the tiny creatures color the ice and make it melt faster.

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What the human genome is lacking compared with the genomes of other primates might have been as crucial to the development of humankind as what has been added during our evolutionary history, according to a new study led by researchers at Yale and the Broad Institute of MIT and Harvard. The new findings, published April 28 in the journal Science, fill an important gap in what is known about historical changes to the human genome.

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Even though it is important to know where these variations are located in the genome, it's also useful to know how or why these genetic variations happened in the first place.

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California sea lions have managed to maintain -- and, in the case of males, increase -- their average body size as their population grows and competition for food becomes fiercer. This is in contrast to other marine mammals, whose average body size tends to decrease as their numbers increase. Researchers report that sexual selection was a strong driving force for males to grow bigger and to strengthen muscles in their neck and jaw that help them fight for mates. Both male and female sea lions evaded food shortages by diversifying their diets and, in some cases, foraging further from the shore.

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Scientists found parallels between the neural circuitry that guides locomotion in sea slugs and in more complex animals like mammals.

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A coil-powered robot fish could make underwater exploration more accessible.

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Researchers have identified a previously unknown group of bacteria, called UBA868, as key players in the energy cycle of the deep ocean. They are significantly involved in the biogeochemical cycle in the marine layer between 200 and 1000 meters.

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Roboticists have developed a jellyfish-inspired underwater robot with which they hope one day to collect waste from the bottom of the ocean. The almost noise-free prototype can trap objects underneath its body without physical contact, thereby enabling safe interactions in delicate environments such as coral reefs. Jellyfish-Bot could become an important tool for environmental remediation.

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Genetic analysis links 3,000-year-old bone found in cave to modern Alaska Natives.