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Categories: Anthropology: Early Humans, Biology: Marine
Published How life and geology worked together to forge Earth's nutrient rich crust
(via sciencedaily.com) Original source Around 500 million years ago life in the oceans rapidly diversified. In the blink of an eye -- at least in geological terms -- life transformed from simple, soft-bodied creatures to complex multicellular organisms with shells and skeletons. Now, research has shown that the diversification of life at this time also led to a drastic change in the chemistry of Earth's crust -- the uppermost layer we walk on and, crucially, the layer which provides many of the nutrients essential to life.
Published Basic 'toolkit' for organ development is illuminated by sea star
(via sciencedaily.com) Original source 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.
Published Earth's first animals had particular taste in real estate
(via sciencedaily.com) Original source 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.
Published Evidence of Ice Age human migrations from China to the Americas and Japan
(via sciencedaily.com) Original source 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.
Published Nose shape gene inherited from Neanderthals
(via sciencedaily.com) Original source Humans inherited genetic material from Neanderthals that affects the shape of our noses, finds a new study.
Published Gutless marine worms on a Mediterranean diet: Animals can synthesize phytosterols
(via sciencedaily.com) Original source 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.
Published How seaweed has been misleading scientists about reef health
(via sciencedaily.com) Original source 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.
Published Scientists recover an ancient woman's DNA from a 20,000-year-old pendant
(via sciencedaily.com) Original source 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.
Published Indo-Pacific corals more resilient to climate change than Atlantic corals
(via sciencedaily.com) Original source 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.
Published Scientists present evidence for a billion-years arms race between viruses and their hosts
(via sciencedaily.com) Original source 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.
Published Information 'deleted' from the human genome may be what made us human
(via sciencedaily.com) Original source 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.
Published Mammalian evolution provides hints for understanding the origins of human disease
(via sciencedaily.com) Original source 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.
Published Male California sea lions are becoming bigger and better fighters as their population rebounds
(via sciencedaily.com) Original source 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.
Published Twilight zone at risk from climate change
(via sciencedaily.com) Original source Life in the ocean's 'twilight zone' could decline dramatically due to climate change, new research suggests.
Published Brain circuits for locomotion evolved long before appendages and skeletons
(via sciencedaily.com) Original source Scientists found parallels between the neural circuitry that guides locomotion in sea slugs and in more complex animals like mammals.
Published Ocean ecosystem: Mixotrophic microorganisms play key role
(via sciencedaily.com) Original source 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.
Published Jellyfish-like robots could one day clean up the world's oceans
(via sciencedaily.com) Original source 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.
Published Searching for ancient bears in an Alaskan cave led to an important human discovery
(via sciencedaily.com) Original source Genetic analysis links 3,000-year-old bone found in cave to modern Alaska Natives.
Published Whales stop by Gold Coast bay for day spa fix with full body scrubs
(via sciencedaily.com) Original source A new Griffith University study has found that humpback whales will use sandy, shallow bay areas to 'roll' around in sandy substrates to remove dead skin cells on their return journeys south to cooler waters. Using data and footage collected from the tags, whales were observed performing full and side rolls in up to 49m water depth on the sea floor that was lined with fine sand or rubble.
Published Elephant seals drift off to sleep while diving far below the ocean surface
(via sciencedaily.com) Original source For the first time, scientists have recorded brain activity in a free-ranging, wild marine mammal, revealing the sleep habits of elephant seals during the months they spend at sea. The new findings show that while elephant seals may spend 10 hours a day sleeping on the beach during the breeding season, they average just 2 hours of sleep per day when they are at sea on months-long foraging trips. They sleep for about 10 minutes at a time during deep, 30-minute dives, often spiraling downward while fast asleep, and sometimes lying motionless on the seafloor.