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Categories: Geoscience: Geology, Offbeat: Paleontology and Archeology
Published Did a magnetic field collapse trigger the emergence of animals?
(via sciencedaily.com) Original source Researchers uncovered compelling evidence that Earth's magnetic field was in a highly unusual state when the macroscopic animals of the Ediacaran Period -- 635 to 541 million years ago -- diversified and thrived. Their study raises the question of whether these fluctuations in Earth's ancient magnetic field led to shifts in oxygen levels that may have been crucial to the proliferation of life forms millions of years ago.
Published Human activity is causing toxic thallium to enter the Baltic sea, according to new study
(via sciencedaily.com) Original source Human activities account for 20% to more than 60% of toxic thallium entering the Baltic Sea over the past eight decades, according to new research. Currently, the amount of thallium, which is considered the most toxic metal for mammals, remains low in Baltic seawater. Much of the thallium in the Baltic, which is the largest human-induced hypoxic area on Earth, has been accumulated in the sediment thanks to sulfide minerals.
Published 75,000-year-old female Neanderthal from cave where species buried their dead
(via sciencedaily.com) Original source A new documentary has recreated the face of a 75,000-year-old female Neanderthal whose flattened skull was discovered and rebuilt from hundreds of bone fragments by a team of archaeologists and conservators.
Published Rock solid evidence: Angola geology reveals prehistoric split between South America and Africa
(via sciencedaily.com) Original source A research team has found that ancient rocks and fossils from long-extinct marine reptiles in Angola clearly show a key part of Earth's past -- the splitting of South America and Africa and the subsequent formation of the South Atlantic Ocean.
Published The double-fanged adolescence of saber-toothed cats
(via sciencedaily.com) Original source How did North America's saber-toothed cats hunt without breaking their unwieldy saber-like canines, which are vulnerable to sideways bending stresses? A paleontologist provides mechanical evidence that during adolescence, when young cats were learning to hunt, their baby teeth remained in place for up to 30 months to laterally buttress the emerging permanent sabers. By the time the baby teeth fell out, presumably the adult cat knew how to protect its sabers during attacks.
Published T. Rex not as smart as previously claimed
(via sciencedaily.com) Original source Dinosaurs were likely as smart as reptiles but not as intelligent as monkeys.
Published Ancient Maya blessed their ballcourts
(via sciencedaily.com) Original source Using environmental DNA analysis, an international team of researchers identified a collection of plants used in ceremonial rituals in the ancient Maya city of Yaxnohcah in Mexico. The plants, known for their religious associations and medicinal properties, were discovered beneath a plaza floor where a ballcourt was built.
Published Human activities have an intense impact on Earth's deep subsurface fluid flow
(via sciencedaily.com) Original source Hydrologists predict human-induced underground fluid fluxes to rise with climate change mitigation strategies like carbon sequestration.
Published These giant, prehistoric salmon had tusk-like teeth
(via sciencedaily.com) Original source Oncorhynchus rastrosus, a giant species of salmon that lived in the North American Pacific Northwest a few million years ago, sported a pair of front teeth that projected out from the sides of its mouth like tusks, according to a new study.
Published Researchers find oldest undisputed evidence of Earth's magnetic field
(via sciencedaily.com) Original source A new study has recovered a 3.7-billion-year-old record of Earth's magnetic field, and found that it appears remarkably similar to the field surrounding Earth today.
Published Scientists unveil genetics behind development of gliding
(via sciencedaily.com) Original source Researchers explain the genomic and developmental basis of the patagium, the thin skin membrane that allows some mammalian species to soar through the air.
Published Bioluminescence first evolved in animals at least 540 million years ago
(via sciencedaily.com) Original source Bioluminescence first evolved in animals at least 540 million years ago in a group of marine invertebrates called octocorals, according to the results of a new study. The study focuses on an ancient group of marine invertebrates that includes soft corals, pushes back the previous oldest dated example of trait by nearly 300 million years.
Published Fossil frogs share their skincare secrets
(via sciencedaily.com) Original source Palaeontologists have solved a hundred-year-old mystery of how some fossil frogs preserve their fleshy parts -- it's all down to their skin. Palaeontologists studied 45-million-year-old fossil frogs from the Geiseltal site in central Germany. Remarkably, the fossils show full body outlines of the soft tissues. The team discovered that the excellent condition of the fossil frogs is due to preservation of ancient skin remnants.
Published The Italian central Apennines as a source of CO2
(via sciencedaily.com) Original source Tectonically active mountains play an important role in the natural CO2 regulation of the atmosphere. Competing processes take place here: At Earth's surface, erosion drives weathering processes that absorb or release CO2, depending on the type of rock. At depth, the heating and melting of carbonate rock leads to the outgassing of CO2 at the surface. In the central Italian Apennine Mountains, researchers have now investigated and balanced all of these processes in one region for the first time -- using, among others, analyses of the CO2 content in mountain rivers and springs.
Published Scientists trigger mini-earthquakes in the lab
(via sciencedaily.com) Original source Earthquakes and landslides are famously difficult to predict and prepare for. By studying a miniature version of the ground in the lab, scientists have demonstrated how these events can be triggered by a small external shock wave. Bring a flotation device: it involves the ground briefly turning into a liquid!
Published One third of China's urban population at risk of city sinking, new satellite data shows
(via sciencedaily.com) Original source Land subsidence is overlooked as a hazard in cities, according to new research. Scientists used satellite data that accurately and consistently maps land movement across China.
Published First evidence of human occupation in lava tube cave in Saudi Arabia
(via sciencedaily.com) Original source New research has highlighted an area in Arabia that once acted as a key point for cultural exchanges and trades amongst ancient people -- and it all took place in vast caves and lava tubes that have remained largely untapped reservoirs of archaeological abundance in Arabia. Through meticulous excavation and analysis, the international team uncovered a wealth of evidence at Umm Jirsan, spanning from the Neolithic to the Chalcolithic/Bronze Age periods (~10,000-3,500 years ago).
Published Paleontologists unearth what may be the largest known marine reptile
(via sciencedaily.com) Original source The fossilized remains of a second gigantic jawbone measuring more than two meters long has been found on a beach in Somerset, UK.
Published Evolution's recipe book: How 'copy paste' errors cooked up the animal kingdom
(via sciencedaily.com) Original source A series of whole genome and gene duplication events that go back hundreds of millions of years have laid the foundations for tissue-specific gene expression, according to a new study. The 'copy-paste' errors allowed animals to keep one copy of their genome or genes for fundamental functions, while the second copy could be used as raw material for evolutionary innovation. Events like these, at varying degrees of scale, occurred constantly throughout the bilaterian evolutionary tree and enabled traits and behaviours as diverse as insect flight, octopus camouflage and human cognition.
Published Even the simplest marine organisms tend to be individualistic
(via sciencedaily.com) Original source Sport junkie or couch potato? Always on time or often late? The animal kingdom, too, is home to a range of personalities, each with its own lifestyle. Biologists report on a surprising discovery: even simple marine polychaete worms shape their day-to-day lives on the basis of highly individual rhythms. This diversity is of interest not just for the future of species and populations in a changing environment, but also for medicine.