Taxonomy term

lucas joel

Magnesium part of Earth's magnetic field engine

Earth’s magnetic field, which arises from convective flows in the planet’s core, known as the geodynamo, has existed for at least 3.4 billion years, meaning that the field-generating processes must have existed for that long as well. But what exactly those processes have looked like throughout Earth’s history, particularly early on, has been poorly understood. In a new study, researchers suggest that magnesium mineral formation in the core is a previously unrecognized but important piece of the puzzle.

26 Apr 2016

Bat signals

Bats, the only true-flight mammals, first appeared during the Early Eocene after a period of acute global warming known as the Paleocene-Eocene Thermal Maximum. Despite decades of study, however, much remains unknown about bats. Recent discoveries are shedding new light on the natural history of these creatures, which today comprise one of the most diverse mammalian groups.

07 Apr 2016

Mammoths may have suffered from bone disease

The demise of mammoths, which went extinct by the end of the Pleistocene about 12,000 years ago, is thought to have been brought about by a combination of climate change and overhunting by early humans. A new study indicates that another culprit might have contributed as well: Mammoth bones retrieved from Northern Eurasia — from sedimentary strata close to the animals’ last known appearance in the fossil record — appear to show evidence for bone diseases associated with nutrient deficiencies.
 
28 Feb 2016

Scarps and craters reveal moon's dynamic side

During their 1972 mission to the moon, Apollo 17 astronauts Eugene Cernan and Harrison Schmitt tried to ascend a steep rise in the lunar rover. The rover could not make it, so the pair drove up the incline in a zigzag pattern. The rise, it was later found, is the lobate scarp of a lunar thrust fault — one of many such features that, thanks to detailed images from NASA’s Lunar Reconnaissance Orbiter (LRO), are now known to occur across the moon’s surface. In a new study, researchers suggest these faults were formed by the same gravitational forces that cause the rise and fall of tides on Earth.

19 Feb 2016

Down to Earth With: Yosemite's first park geologist Greg Stock

As a child growing up in the foothills of California’s Sierra Nevada Mountains, Greg Stock and his family took frequent trips to Yosemite National Park. One of his first memories is of hearing and seeing a giant rockfall tumble down the face of El Capitán. Today, Stock studies such rockfalls and how they impact safety in the area as the first park geologist employed at Yosemite. 
 
09 Feb 2016

Benchmarks: February 1962 and 1984: John Glenn and Bruce McCandless make space flight history

On the morning of Feb. 20, 1962, John H. Glenn sat inside the Mercury Friendship 7 space capsule, perched atop a rocket that had initially been designed to deliver nuclear warheads to the far ends of the world. That rocket would propel Glenn into space, and into the history books, as the first American to orbit Earth. 
 
07 Feb 2016

Travels in Geology: Rocks and Climbing at Kentucky's Red River Gorge

People don’t often think of Kentucky as a destination to hike and rock climb amid dramatic sandstone arches and red rock gorges. But maybe they should.

04 Feb 2016

Getting there and getting around Kentucky's Red River Gorge

Entry to Daniel Boone National Forest and the Red River Gorge is free. The nearest airports are in Lexington and Louisville, Ky., both about an hour away by car. Cincinnati is two hours away. Having a car is a must for getting to and driving around the Red. 
 
04 Feb 2016

Permian-Triassic extinctions timed differently on land and at sea

Life on land and in the sea was nearly eradicated about 252 million years ago in the largest-known mass extinction. The cataclysm, known as the Permian-Triassic (P-T) mass extinction, was likely driven by extensive flood basalt volcanism in Siberia and is thought to have affected global biodiversity simultaneously. However, based on analyses of rocks deposited around the time of the P-T boundary in the Karoo Basin of South Africa, scientists suggest in a new study that the terrestrial turnover in vertebrates occurred earlier than the marine extinction. If true, a second trigger — other than Siberian volcanism — might need to have occurred to explain both events.
 
31 Jan 2016

Land plants came prepared for terrestrial life

Plants colonized land between 450 million and 420 million years ago, and, once there, they drastically altered terrestrial landscapes and provided resources for animals leaving the oceans around the same time. One adaptation that helped plants gain a foothold on land is a symbiosis with fungi known as arbuscular mycorrhizae (AM), which help plants acquire water and key nutrients from the soil and are still associated with most land plants today. In return, plants provide the fungi with bioavailable carbon produced during photosynthesis. When this symbiosis evolved has remained unclear, but researchers recently discovered that it likely has roots in a group of freshwater algae ancestral to land plants.
 
22 Jan 2016

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