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Categories: Geoscience: Oceanography, Paleontology: Early Mammals and Birds
Published Tiny scales reveal megalodon was not as fast as believed, but it had a mega-appetite explaining its gigantism
(via sciencedaily.com) Original source A new study reveals the iconic extinct Megalodon, or 'megatooth shark', was a rather slow cruiser that used its warm-bloodedness to facilitate digestion and absorption of nutrients.
Published Evolutionary origins of the pygmy right whale
(via sciencedaily.com) Original source Researchers have finally settled a decades-long dispute about the evolutionary origins of the pygmy right whale.
Published Fossils reveal how ancient birds molted their feathers -- which could help explain why ancestors of modern birds survived when all the other dinosaurs died
(via sciencedaily.com) Original source Birds are the only group of dinosaurs that survived the asteroid-induced mass extinction 66 million years ago. But not all the birds alive at the time made it. Why the ancestors of modern birds lived while so many of their relatives died has been a mystery that paleontologists have been trying to solve for decades. Two new studies point to one possible factor: the differences between how modern birds and their ancient cousins molt their feathers.
Published There may be good news about the oceans in a globally warmed world
(via sciencedaily.com) Original source An analysis of oxygen levels in Earth's oceans may provide some rare, good news about the health of the seas in a future, globally warmed world. A study analyzing ocean sediment shows that ocean oxygen levels in a key area were higher during the Miocene warm period, some 16 million years ago when the Earth's temperature was hotter than it is today.
Published A jaw-dropping conundrum: Why do mammals have a stiff lower jaw?
(via sciencedaily.com) Original source The lower jaws of lizards, birds, fish and even dinosaurs are comprised of multiple bones per side. Yet mammals diverged from all other vertebrates and settled on just one bone, repurposing the extra bones into a more elaborate inner ear, perhaps the better to hear. The single bone per side, fused in primates into one jawbone, makes the jaw more rigid. A paleontologist asks, Did the stiffer, rigid jaw make mammals more successful?
Published Humans' ancestors survived the asteroid impact that killed the dinosaurs
(via sciencedaily.com) Original source A Cretaceous origin for placental mammals, the group that includes humans, dogs and bats, has been revealed by in-depth analysis of the fossil record, showing they co-existed with dinosaurs for a short time before the dinosaurs went extinct.
Published New research finds that more than 90% of global aquaculture faces substantial risk from environmental change
(via sciencedaily.com) Original source Many of the world's largest aquatic food producers are highly vulnerable to human-induced environmental change, with some of the highest-risk countries in Asia, Latin America and Africa demonstrating the lowest capacity for adaptation, a landmark study has shown.
Published Research in a place where geological processes happen before your eyes
(via sciencedaily.com) Original source Taiwan experiences some of the world's fastest rates of mountain building -- they are growing at a faster rate than our fingernails grow in a year. The mountains also see frequent and significant earthquakes, the region experiences about four typhoons per year on average, and in some places, it receives upwards of several meters of rain annually.
Published Study of deep-sea corals reveals ocean currents have not fuelled rise in atmospheric carbon dioxide
(via sciencedaily.com) Original source Pioneering analysis of deep-sea corals has overturned the idea that ocean currents contributed to increasing global levels of carbon dioxide in the air over the past 11,000 years.
Published Megalodon was no cold-blooded killer
(via sciencedaily.com) Original source How the megalodon, a shark that went extinct 3.6 million years ago, stayed warm was a matter of speculation among scientists. Using an analysis of tooth fossils from the megalodon and other sharks of the same period, a study suggests the animal was able to maintain a body temperature well above the temperature of the water in which it lived. The finding could help explain why the megalodon went extinct during the Pliocene Epoch.
Published Extinct warbler's genome sequenced from museum specimens
(via sciencedaily.com) Original source The Bachman's warbler, a songbird that was last seen in North America nearly 40 years ago, was a distinct species and not a hybrid of its two living sister species, according a new study in which the full genomes of seven museum specimens of the bird were sequenced.
Published Are viruses keeping sea lice at bay in wild salmon?
(via sciencedaily.com) Original source More than 30 previously unknown RNA viruses in sea lice have been identified. Sea lice are parasitic copepods (small crustaceans) found in many fresh and saltwater habitats, and have been implicated in the decline of wild salmon populations. The research sheds greater light on the types of viruses being carried by sea lice, and how the viruses and host are interacting.
Published Antarctic ice shelves experienced only minor changes in surface melt since 1980
(via sciencedaily.com) Original source A team of glaciologists set out to quantify how much ice melt occurred on Antarctica's ice shelves from 1980 to 2021. The results might seem to be good news for the region, but the researchers say there's no cause for celebration just yet.
Published Caribbean seagrasses provide services worth $255B annually, including vast carbon storage, study shows
(via sciencedaily.com) Original source Caribbean seagrasses provide about $255 billion in services to society annually, including $88.3 billion in carbon storage, according to a new study. The study has put a dollar value on the many services -- from storm protection to fish habitat to carbon storage -- provided by seagrasses across the Caribbean, which holds up to half the world's seagrass meadows by surface area and contains about one-third of the carbon stored in seagrasses worldwide.
Published Scientists unearth 20 million years of 'hot spot' magmatism under Cocos plate
(via sciencedaily.com) Original source A team of scientists has observed past episodic intraplate magmatism and corroborated the existence of a partial melt channel at the base of the Cocos Plate. Situated 60 kilometers beneath the Pacific Ocean floor, the magma channel covers more than 100,000 square kilometers, and originated from the Galápagos Plume more than 20 million years ago, supplying melt for multiple magmatic events -- and persisting today.
Published Massive underwater plateau near Solomon Islands is younger and its eruption was more protracted than previously thought
(via sciencedaily.com) Original source The Ontong Java Plateau, a volcanically-formed underwater plateau located in the Pacific Ocean north of the Solomon Islands, is younger and its eruption was more protracted than previously thought, new research suggests.
Published 10-year countdown to sea-ice-free Arctic
(via sciencedaily.com) Original source Research team predicts Arctic without ice by the end of 2030s if current increasing rate of greenhouse gas emission continues.
Published Scientists discover urea in atmosphere revealing profound consequences for climate
(via sciencedaily.com) Original source Areas of the ocean that are rich in marine life are having a bigger impact on our ecosystems and the climate than previously thought, new research suggests.
Published Hotter sand from microplastics could affect sea turtle development
(via sciencedaily.com) Original source New research has found that extreme concentrations of microplastics could increase the temperature of beach sand enough to threaten the development of incubating sea turtles.
Published Geologists challenge conventional view of Earth's continental history, stability with new study
(via sciencedaily.com) Original source The seemingly stable regions of the Earth's continental plates -- the so-called stable cratons -- have suffered repetitive deformation below their crust since their formation in the remote past, according to new research from the University of Illinois Urbana-Champaign. This hypothesis defies decades of conventional plate tectonics theory and begs to answer why most cratons have remained structurally stable while their underbellies have experienced significant change.