Taxonomy term

mary caperton morton

Mastodon bones point to significantly earlier human presence in North America

In 1992, paleontologists from the San Diego Natural History Museum discovered a set of fossil bones, tusks and teeth from a single mastodon next to state highway 54 south of San Diego. Archaeologists were soon called to investigate the site, which also featured several large cobblestones — unique in the otherwise sandy matrix surrounding the bones — that seemed to have been used to break open the mastodon’s long bones, hinting at human activity soon after the animal’s death. A reliable age for the intriguing find has eluded scientists for more than two decades, but in a study released today in Nature, researchers who successfully dated the bones have come to a sensational conclusion: The site appears to date back roughly 130,000 years, more than 100,000 years before humans are thought to have lived in North America.

26 Apr 2017

Tallying temperature drops inside tornadoes

The inside of a strong tornado is an intense place, with wind speeds of more than 450 kilometers per hour and dramatic drops in air pressure and temperature. But due to the dangerous unpredictability of such storms, few real-time measurements have been taken inside actual twisters. In a new study, researchers took a mathematical approach to circumvent the danger and calculate temperature changes inside tornadoes, offering a glimpse into how these violent storms operate.

24 Apr 2017

Massive dust storm caused by climate, not conflict

In August and September 2015, a massive dust storm swept across the Middle East, engulfing seven nations in sand thick enough to ground flights, trigger respiratory distress for many, and obscure the region from satellites. At the time, the unprecedented size of the storm was blamed on the ongoing conflict in Syria, with unusual amounts of dust being raised from abandoned agricultural lands and increased military traffic. But a new study cites a combination of climatic factors and weather as the more likely culprits.

20 Apr 2017

Tiny dinosaur-era marsupial packed a big bite

Newly described fossils from one of the earliest-known marsupials are shedding light on the evolution of mammals during the Mesozoic and revealing an animal with an impressive bite, perhaps strong enough to take down a dinosaur.

19 Apr 2017

Did the first humans arrive in North America a lot earlier?

New dating of artifacts recovered from a site in the northern Yukon, on the Alaskan border, may push back the hypothesized entry date of the first American colonizers via a northwestern route — long thought to have occurred over the Bering land bridge between 18,000 and 14,000 years ago — by several thousand years.

10 Apr 2017

Breakup of Pangea led to thicker oceanic crust

Oceanic crust formed at mid-ocean spreading centers, like the Mid-Atlantic Ridge, is recycled back into the mantle at subduction zones. Aside from isolated chunks that might be even older, the oldest crust found on Earth today is thought to be about 200 million years old. This old crust, portions of which are found along the outer margins of the Atlantic, Pacific and Indian oceans, is much thicker than the crust being produced today — in some places by almost 2 kilometers — according to a new study, a finding that may suggest that Earth’s supercontinent cycle affects how Earth’s interior cools.

07 Apr 2017

Of airplanes and ash clouds: What we've learned since Eyjafjallajökull

The havoc created when Iceland’s Eyjafjallajökull Volcano erupted in 2010 and closed trans-Atlantic and northern European airspace for days also created research opportunities. Scientists, engineers and the airline industry have been working together to figure out how to keep the aviation system going when volcanic ash can’t be avoided.
02 Apr 2017

Warning: Ash Ahead!

One of the next-generation tactics being pursued by engineers is the use of ash-sensing equipment installed on airplanes that could warn of an ash cloud ahead and allow pilots time to adjust their flight path to avoid the cloud. “If you’re driving a car and you see a hazard up ahead, you can navigate around it,” says Fred Prata of the University of Oxford in England. “Every aircraft has radar equipment with which [pilots] can see weather systems and fly around them. This is the same concept, but adapted to image volcanic ash.”

02 Apr 2017

Ash vs. airplanes

Between 1953 and 2009,* there were 129 reported incidents of airplane-ash encounters, with 79 of those causing some degree of airframe or engine damage. Twenty-six involved significant or severe damage, and nine involved some degree of engine shutdown during flight. Most of the encounters occurred within 24 hours of the onset of ash production during an eruption and within 1,000 kilometers of the source volcano. All flights landed safely.

02 Apr 2017

Dental plaque reveals later start date for hominin cooking

Ancient teeth have long been a source of information about ancient diets, mainly through analyses of isotopic compositions and wear patterns. In a new study published in the Science of Nature, researchers studied microfossils of food particles extracted from the teeth of a 1.2-million-year-old unidentified hominin found at the Sima del Elefante site in northern Spain. The microfossils include traces of raw animal tissue, uncooked starch granules from grasses, pollen grains from a species of pine tree and insect fragments. The lack of charring of the recovered fibers and an absence of micro-charcoal suggest the bearer of the teeth neither cooked his or her food nor spent significant time around a fire source.

30 Mar 2017

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