Taxonomy term

lucas joel

TRAPPIST-1 system hosts seven "Earth-like" planets

In 2017, astronomers discovered seven planets orbiting a star dubbed TRAP­PIST-1, a faint red dwarf 40 light-years from Earth and only 9 percent as bright as our sun. The Earth-like qualities of these planets made headlines: they are of similar sizes to our planet, and their orbits fall within TRAPPIST-1’s habitable zone — two characteristics that scientists think are important for life to exist on a planet. Researchers now report that the TRAPPIST-1 planets have even more traits in common with Earth: they are likely rocky, and they may have surface water that exists as liquid, ice and vapor.

08 Jun 2018

Getting there and getting around Idaho

If you’re interested in a trip down the Main Salmon, you have two options: put a trip together yourself, or hire a professional outfitter to take you.

06 Jun 2018

Travels in Geology: Rafting the Salmon River through the Idaho Batholith

Rafting down the Main Salmon River, which courses north and then west across northern Idaho, takes you by Precambrian metamorphics and the granites of the Idaho Batholith. Six to eight days later, your trip concludes as you float past what was once the edge of North America, and over former island arcs sutured onto the continent during the Mesozoic.
06 Jun 2018

Cape Town faces a waterless future

The city of Cape Town, South Africa, is bone dry. In 2017, after two straight years of drought, a third drought year offered more of the same.. This past January, city leaders announced that they would shut off the taps to the municipal water supply in April because that was when “Day Zero” — the day when the water supply would run dry — was predicted to occur. Day Zero has since been pushed back to sometime in 2019, but, for 4 million Capetonians, living under the specter of a day without water is the new normal, and signs of that reality litter the city. Sometimes literally.

22 May 2018

Origins of plant photosynthesis illuminated

Photosynthesis, the process by which plants harness sunlight to make their food, is a defining feature of plants and an important evolutionary development. But when photosynthesis evolved in ancient plant ancestors is not clear. The Precambrian fossil red alga Bangiomorpha pubescens, discovered in the Canadian Arctic in 1990 by University of Cambridge paleobiologist Nicholas Butterfield, displays evidence of traits that suggest it photosynthesized the way plants do, but the exact age of the fossil was also unknown. In a new study, researchers report an age for the alga of about 1.047 billion years, making it the oldest-known direct ancestor of plants.

25 Apr 2018

Whatever happened to thagomizers and other tail weapons?

Stegosaurus wielded a spiked tail — dubbed a “thagomizer” by cartoonist Gary Larson and informally adopted by paleontologists — which the herbivorous dinosaur likely used for defense against hungry predators. Other extinct animals also sported foe-clobbering tail weapons: Ankylosaurus had a tail club, as did extinct mammals like the glyptodonts, giant armadillo-like animals that once roamed the Americas. Today, though, thagomizers and bony tail clubs are things of the past. In a new study, paleontologists have found that extinct animals with such weapons all shared a now-antiquated set of traits: They were large, herbivorous, and had body armor and a stiff torso.

23 Apr 2018

Coal formation nearly froze Earth

Burning coal releases carbon dioxide, which warms the planet when the gas escapes into the air. On the flip side, coal formation sequesters carbon dioxide removed from the atmosphere by plants, which contributes to global cooling as the planet’s greenhouse gas blanket thins. According to new research, so much carbon was removed from the atmosphere in the Carboniferous Period, when most of Earth’s coal reserves formed, that the planet became almost completely covered in ice.

21 Feb 2018

What drives hot spots of sea-level rise?

As sea levels creep up around the world, scientists have observed hot spots where regional rates of sea-level rise greatly outpace the global average. But what drives the formation of these hot spots, and how long they last, have been mysteries. In a new study, scientists tracking sea levels along the Florida coast suggest that the combined effects of two naturally occurring climate processes, the El Niño-Southern Oscillation (ENSO) and the North Atlantic Oscillation (NAO), control sea-level hot spot formation along the U.S. East Coast.

01 Dec 2017

Chemical clues illuminate fossil plant relationships

To reconstruct relationships among extinct plants and animals, paleontologists often compare genetic sequences from distinct organisms or analyze differences in fossil shapes. But both techniques have limitations: DNA does not last more than about a million years in the rock record, so genetic comparisons are typically limited to relatively recent species; and finding fossils intact enough to use for shape comparisons can be difficult. In a recent study, scientists describe a new technique that could help get around these issues — for some plants at least — using molecular remnants that are more robust than DNA and are preserved in fossil leaves.

17 Oct 2017

Volcanism triggered end-Triassic extinction

The end-Triassic mass extinction exterminated up to three-quarters of all species on land and in the oceans 201 million years ago. This die-off opened up ecological niches and allowed for, among other changes, dinosaurs to diversify and spread across terrestrial ecosystems during the rest of the Mesozoic. Volcanism has long been implicated in the extinction, but whether it had a major impact on the planet at the time has remained unclear. In new research, scientists observed elevated mercury concentrations in extinction-aged rocks from around the world. Because volcanism is the main nonanthropogenic source of mercury in the environment, the findings suggest that volcanic activity was likely the main extinction trigger at the end of the Triassic.

21 Sep 2017

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