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News

Marine megafaunal extinction discovered

Extinctions of large land animals during the Pleistocene are well documented. In a new study, scientists report that marine megafauna also suffered severe losses several million years ago, around the time that the first hominid ancestors were emerging in Africa.

17 Nov 2017

Volcanic activity contributed to first of the "Big Five" mass extinctions

During the Ordovician, between about 488 million and 444 million years ago, plant life first emerged on land, while primitive fish and a variety of marine invertebrates flourished in the oceans. Toward the end of the period, however, a mass extinction — the first of the so-called “Big Five” Phanerozoic extinctions — wiped out roughly 60 percent of all marine invertebrate genera. In a recent study, researchers shed new light on a possible cause of the Late Ordovician extinction: volcanic activity.

15 Nov 2017

Ice (Re)Cap: November 2017

From Antarctica to the Arctic; from polar caps, permafrost and glaciers to ocean-rafted sea ice; and from burly bears to cold-loving microbes, fascinating science is found in every nook and crevasse of Earth’s cryosphere, and new findings are announced often. Here are a few of the latest updates.

 
14 Nov 2017

Microbes influence ooid formation

The formation of carbonate spheroids called ooids is a bit of a mystery. They are thought to form in warm waters saturated with carbonate, which combines with calcium to form concentric layers of calcium carbonate on shell fragments or sand grains. Some scientists have suggested that the presence of microbes might encourage calcium carbonate to precipitate out of water to form ooids in a process called organomineralization.

10 Nov 2017

Second stars can distort planet size estimates

When light from a star is blocked by another celestial body — as when the moon obstructed light from the much-larger sun during the recent solar eclipse — astronomers can estimate the density of exoplanets that orbit the star. And from the density, they can determine whether a planet is rocky like Earth or gaseous like Jupiter. But a new study in the Astronomical Journal shows that such density assessments, which are normally calculated from the size of the planet, may be skewed by the presence of “hidden” stars.

08 Nov 2017

Humans arrived Down Under earlier than thought

Analysis of sediments surrounding a trove of artifacts discovered in northern Australia suggests the first humans arrived on the continent about 10,000 years earlier than previously thought, a finding that has implications for the hypothesized role of humans in the extinctions of Australian megafauna.

07 Nov 2017

Pharmaceuticals in urban sediments reveal wastewater treatment effectiveness

People take pills to relieve headaches or syrups to ease a hacking cough, and eventually these medications can make their way into streams and rivers around the world as humans excrete the chemicals. Scientists are now using concentrations of common pharmaceutical products (PPs) in river sediments in Orléans, France, to determine how effective four water treatment plants have been at removing chemicals from the environment.

03 Nov 2017

When agriculture went to our heads

The dawn of agriculture left an indelible mark on early human societies, and a new study finds that eating softer, cultivated foods subtly changed the shape of human skulls. Scientists have long suspected that the transition from hunting and foraging to farming and raising livestock would have affected our skulls, specifically the mandible and other anatomy involved in chewing, but quantifying such changes has proven difficult.

01 Nov 2017

Northern Finns didn't starve during Little Ice Age

Today, Finland’s Northern Ostrobothnia region is one of the northernmost places in Europe that can support agriculture. But how this region fared during the Little Ice Age — a period of globally cooler temperatures that lasted roughly from A.D. 1300 to 1850 — is unknown. Scientists assume the climatic cooling would have adversely affected food supplies. Now, however, the discovery of a mysterious medieval cemetery in northern Finland dating to the middle of the Little Ice Age is offering clues that the inhabitants were well fed and well suited to the northern clime.

31 Oct 2017

How long will the lava flow? Predicting eruption durations with satellite monitoring

If you live near a lava-spewing volcano, it could be helpful to know just how long molten rock might flow during a fiery eruption. In a new study, scientists report that they can calculate how long lava-flowing eruptions might last based on satellite data.

27 Oct 2017

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