A Smithsonian-led team of researchers have discovered North America’s oldest known pterosaur, the winged reptiles that lived alongside dinosaurs and were the first vertebrates to evolve powered flight. In a paper published today, July 7, in Proceedings of the National Academy of Sciences, researchers led by paleontologist Ben Kligman, a Peter Buck Postdoctoral Fellow at the Smithsonian’s National Museum of Natural History, present the fossilized jawbone of the new species and describe the sea gull-sized pterosaur alongside hundreds of other fossils—including one of the world’s oldest turtle fossils—unearthed at a remote bonebed in Petrified Forest National Park in Arizona.

These fossils, which date back to the late Triassic period around 209 million years ago, preserve a snapshot of a dynamic ecosystem where older groups of animals, including giant amphibians and armored crocodile relatives, lived alongside evolutionary upstarts like frogs, turtles and pterosaurs.

A new autonomous underwater vehicle imaged a previously unexplored portion of the seafloor in ultra-deep waters near the Mariana Trench. Operationalizing this technology for the first time was part of a mission led by the Ocean Exploration Cooperative Institute, based at the University of Rhode Island’s Graduate School of Oceanography, with support from the National Oceanic and Atmospheric Administration, the Bureau of Ocean Energy Management, and the U.S. Geological Survey.

Due to the radiative thermal conductivity of the mineral olivine, only oceanic plates over 60 million years old and subducting at more than 10 centimeters per year remain sufficiently cold to transport water into the Earth's deep mantle. This was found by scientists from the University of Potsdam and from the Helmholtz Centre for Geosciences (GFZ) Potsdam, together with international colleagues, by measuring the transparency of olivine under conditions in Earth’s mantle for the first time. Their results were published in the journal “Nature Communications”.

New research identifies the key causes of changes affecting river deltas around the world and warns of an urgent need to tackle them through climate adaptation and policy.

Deltas are low-lying areas that form as rivers and empty their water and sediment into another body of water, such as an ocean, lake, or another river.

Some of the largest in the world, such as the Rhine, Mekong, Ganges-Brahmaputra-Meghna, and Nile, are threatened by climate change, facing rising sea levels and increasing frequency of extreme events.

With approximately 500 million people today living within or adjacent to delta systems, this is a major issue.​

A tiny single-celled organism may have a big impact on how the world’s basic chemical building blocks cycle between living things and the non-living environment. Called Polarella, the algal genus is a dinoflagellate that was once thought to be restricted to polar regions of Earth, but a team has revealed that it is abundant and influential in the Eastern Tropical North Pacific Ocean off the coast of Mexico.

 

Positively and neutrally buoyant microplastics mainly outflow from the Seto Inland Sea into the Pacific Ocean, whereas negatively buoyant MPs hardly leave the Seto Inland Sea and are primarily deposited and degraded near river mouths. Traditional microplastics are difficult to degrade quickly and thus remain in the marine environment for long periods. However, the use of biodegradable microplastics can significantly reduce microplastic pollution in the marine environment, especially in sediments.