Taxonomy term

lucas joel

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

Benchmarks: January 10, 2013: Pinnacles National Park is founded

On Jan. 10, 2013, when President Barack Obama signed legislation granting national park status to the former Pinnacles National Monument — designated as such by President Theodore Roosevelt in 1908 — the land became the country’s 59th national park. Tucked away in California’s Coast Ranges about an hour’s drive inland from Big Sur, Pinnacles covers almost 11,000 hectares of wilderness near Paicines, Calif., and is one of the main refuges for the critically endangered California condor, which nearly went extinct in the 1980s. Recently, with conservation programs like the one that exists at Pinnacles, the birds are on their way toward recovery.
 
10 Jan 2016

Benitoite: A rare gemstone

The tectonic forces that formed Pinnacles also helped form one of the world’s rarest gemstones: benitoite. Gem-quality specimens are only found in San Benito County where Pinnacles National Park is located. Benitoite, which is California’s state gemstone, has a deep azure color, a pyramidal crystal habit, and a light-blue fluorescence under ultraviolet light. 
 
10 Jan 2016

Rainbows reclassified

Rainbows — those arches of color that streak across wet skies — are recognizable to almost everyone. Our understanding of rainbows, though, particularly how they form and the diversity of shapes they can take, is still fuzzy.

21 Dec 2015

Is aviation 'whitening' the sky?

Clear blue skies may not be as clear as they appear. Skies are actually becoming less clear, causing incoming sunlight to scatter in different directions, rather than striking the planet directly — and aviation may be to blame, according to research presented this week at the fall meeting of the American Geophysical Union (AGU) in San Francisco.

17 Dec 2015

Narratives from Nepal: Relief and rebuilding after the Gorkha Earthquake

When a magnitude-7.8 earthquake struck Nepal on April 25, mountaineer Ben Erdmann was on a climbing expedition on Annapurna; meanwhile, seismologist Susan Hough and engineer Ajay Sitaula were at home in California and Colorado, respectively, watching the disaster unfold. Soon after, all would be on the ground in Nepal, involved in relief efforts or working to assess what happened — especially why the quake did not do as much damage as scientists expected it would.

06 Dec 2015

Working near Gorkha's epicenter

Hari Krishna Bhattarai works for the World Wildlife Fund (WWF) in Nepal, as well as for Educating Nepal, an organization that aims to improve the education of Nepali schoolchildren. On Friday, April 24, Bhattarai was working at a field site in Gorkha, tending to various WWF-related projects and working with locals in the Gorkha region. The next day, April 25, was a Nepalese public holiday, so Bhattarai returned to his home city, Pokhara, near the Annapurna Massif. The Gorkha quake struck Saturday, doing little damage to Pokhara. On Monday, Bhattarai returned to the area near Barpak, where he had been working, to deliver relief supplies like beans and rice. 
 
06 Dec 2015

Down to Earth With: Paleobiologist Nigel Hughes

I first met Nigel Hughes, a paleobiologist at the University of California at Riverside (UCR), in 2010. He took me on a brisk walk through the UCR Botanical Gardens, where the trees kept us cool in the hot Southern California sun while he told me all about trilobites. 
 
03 Dec 2015

Warty algae-like sheets survived Snowball Earth events

Between about 730 million and 635 million years ago, during the Cryogenian Period of the Late Proterozoic, Earth is thought to have been almost completely covered in ice twice, events that scientists have termed “Snowball Earth” glaciations. The first global glaciation, the Sturtian, lasted from 730 million to 700 million years ago, and the second, the Marinoan, lasted from 660 million to 635 million years ago. Both glaciations likely put severe limitations on the ability of life — predominately microorganisms — to thrive. 
 
19 Nov 2015

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