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Categories: Ecology: Sea Life, Geoscience: Geology
Published What did the earliest animals look like?
(via sciencedaily.com) Original source Surprisingly, genome comparisons have failed to resolve a major question in animal evolution: Which living animals are the descendants of the earliest animals to evolve in the world's oceans? Scientists performed a detailed chromosomal analysis that comes down definitively in favor of comb jellies, or ctenophores, as the most recent common ancestor of all animals, or the sister taxa to all animals. Sponges evolved later.
Published Physicists take the temperature of fluid flows and discover new role for turbulence
(via sciencedaily.com) Original source A team of physicists has discovered a new role for a specific type of turbulence -- a finding that sheds light on fluid flows ranging from the Earth's liquid core to boiling water.
Published Jaw shapes of 90 shark species show: Evolution driven by habitat
(via sciencedaily.com) Original source 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.
Published 'Warm Ice Age' changed climate cycles
(via sciencedaily.com) Original source Approximately 700,000 years ago, a 'warm ice age' permanently changed the climate cycles on Earth. During this exceptionally warm and moist period, the polar glaciers greatly expanded. A research team identified this seemingly paradoxical connection. The shift in the Earth's climate represents a critical step in our planet's later climate development.
Published Out of this world control on Ice Age cycles
(via sciencedaily.com) Original source A research team, composed of climatologists and an astronomer, have used an improved computer model to reproduce the cycle of ice ages (glacial periods) 1.6 to 1.2 million years ago. The results show that the glacial cycle was driven primarily by astronomical forces in quite a different way than it works in the modern age. These results will help us to better understand the past, present, and future of ice sheets and the Earth's climate.
Published Crushed clams, roaming rays: Acoustic tags reveal predator interactions
(via sciencedaily.com) Original source Inspired by clam fishermen reports, researchers used passive acoustic telemetry to gauge the interactions between two highly mobile rays. They monitored the tagged rays in the wild over two years to see how often and when they visited clam leases, designated underwater locations used to produce hard clams of all sizes from littlenecks to chowders. Results provide both good news and bad news for clammers. Rays spent even more time in these clam lease sites than clammers reported or suspected, but it's not necessarily where they prefer hanging out.
Published Singing humpback whales respond to wind noise, but not boats
(via sciencedaily.com) Original source A new study has found humpback whales sing louder when the wind is noisy, but don't have the same reaction to boat engines.
Published Great Basin: History of water supply in one of the driest regions in the USA
(via sciencedaily.com) Original source An international team has reconstructed the evolution of groundwater in the Great Basin, USA -- one of the driest regions on Earth -- up to 350,000 years into the past with unprecedented accuracy. The results shed new light on the effects of climate change on water supply and provide important insights for the sustainable use of groundwater resources.
Published Global warming puts whales in the Southern Ocean on a diet
(via sciencedaily.com) Original source In the autumn, when right whales swim towards the coasts of South Africa, they ought to be fat and stuffed full. But in recent years, they have become thinner because their food is disappearing with the melting sea ice.
Published Like ancient mariners, ancestors of Prochlorococcus microbes rode out to sea on exoskeleton particles
(via sciencedaily.com) Original source 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.
Published Hammerhead sharks hold their breath on deep water hunts to stay warm
(via sciencedaily.com) Original source 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.
Published Giants of the Jurassic seas were twice the size of a killer whale
(via sciencedaily.com) Original source There have been heated debates over the size of Jurassic animals. The speculation was set to continue, but now a chance discovery in an Oxfordshire museum has led to palaeontologists publishing a paper on a Jurassic species potentially reaching a whopping 14.4 meters -- twice the size of a killer whale.
Published Nature favors creatures in largest and smallest sizes
(via sciencedaily.com) Original source 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.
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 Water warming study shows unexpected impact on fish size
(via sciencedaily.com) Original source The theory that water-breathing animals such as fish will shrink due to global warming has been called into question by a new study.
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 New clues about the rise of Earth's continents
(via sciencedaily.com) Original source New research deepens the understanding of Earth's crust by testing and ultimately eliminating one popular hypothesis about why continental crust is lower in iron and more oxidized compared to oceanic crust. The iron-poor composition of continental crust is a major reason why vast portions of the Earth's surface stand above sea level as dry land, making terrestrial life possible today. The study uses laboratory experiments to show that the iron-depleted, oxidized chemistry typical of Earth's continental crust likely did not come from crystallization of the mineral garnet, as a popular explanation proposed in 2018.
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.