Taxonomy term

mary caperton morton

Mercury's recent tectonics revealed

Not so long ago, Mercury was the least-studied planet in the inner solar system, known only from Earth-based observations and from Mariner 10’s brief flyby in the 1970s. In 2011, the MESSENGER spacecraft began orbiting Mercury, imaging the planet’s crater- and fault-scarred surface before crashing into it, as planned, in 2015. As MESSENGER spiraled downward, it took a last series of high-resolution images, analyses of which are revealing new information about the planet’s surface geology, including evidence for recent tectonic activity.

05 Jan 2017

Earliest evidence of humans in the Americas

Map showing the earliest evidence of humans in the Americas. 

01 Jan 2017

The first Americans: How and when were the Americas populated?

The latest research suggests humans first came to the Americas by boat, though along which coast remains controversial. Archaeologists and geologists are working together to try to solve the mystery of how and when the first Americans arrived. 

 

01 Jan 2017

Underwater archaeology

As the ice sheets melted at the end of the last ice age, sea level rose dramatically, drowning much of the paleo coastline of North and South America under meters of water. To find evidence old enough to be associated with the initial colonizers, archaeologists have to get wet, even donning scuba gear to search for human relics along the Gulf and Atlantic coasts. Such work is highly technical and expensive, but a small handful of divers trained in underwater archaeological excavation techniques insist that it’s worth the trouble. 

01 Jan 2017

Slow-moving slides may be triggered by cold temperatures

Landslides aren’t always fast-moving disasters. Slow landslides creep downhill at rates up to a few meters a year, which might not sound dramatic, but slow slides can still damage roads, pipelines and communities. Slow-moving slides are most commonly triggered by increased pore pressure in the soils due to rainfall or snowmelt, but in some places, according to a new study, temperature may also play a role. The new study looking at slow slides in Japan found that cold underground temperatures — independent of increased rainfall — may lubricate slow-moving slides.

27 Dec 2016

Panama's isthmus stays 3 million years young: Further evidence needed to support an older age

The formation of the tiny Isthmus of Panama had major geographic repercussions, cutting off the Caribbean Sea from the Pacific Ocean and connecting North and South America. A new study using multiple lines of geological, biological and molecular evidence supports the most commonly accepted age of the isthmus, about 3 million years, refuting a pair of 2015 studies that placed the closing at a much earlier date.

27 Dec 2016

Green corridors led humans out of Africa

A trail of fossil, archaeological and genetic clues suggests that modern humans, who first evolved in East Africa about 200,000 years ago, may have made forays outside Africa via the eastern Mediterranean and the Arabian Peninsula as early as 120,000 years ago. But most fossil and archaeological evidence suggests they didn’t begin widely populating the rest of the world until about 60,000 years ago.

26 Dec 2016

Mysterious Antarctic algae blown in by high winds

When fossils of microscopic marine algae called diatoms were discovered high in the Transantarctic Mountains 30 years ago, the mysterious find set off a heated debate about whether Antarctica had thawed enough at some point within the last few million years for the emergence of algae-rich seas in the middle of the continent, or whether the diatoms were blown far inland by wind. Now, a new study links the two hypotheses: Researchers led by Reed Scherer of Northern Illinois University found that the algae were likely deposited by strong winds after substantial ice-sheet melt led to sea-level rise along eastern Antarctica.

23 Dec 2016

Tiniest pterosaur found in British Columbia

Pterosaurs have a gargantuan reputation: Most fossils of the flying reptiles have wingspans similar to a small plane. But the recent discovery of fragmentary fossils from an eagle-sized specimen in British Columbia shows that not all pterosaurs were huge.

19 Dec 2016

Extinct tiger had unique elbow, hunting style

During the Pleistocene, the marsupial lion, Thylacoleo carnifex, was one of Australia’s top predators. Fossil records indicate the jaguar-sized cat died out between 20,000 and 10,000 years ago (although rumors persist the “Queensland Tiger” may still survive in isolated habitats). In a new study examining Thylacoleo fossils, researchers have now found an elbow joint unique among living predatory mammals.

16 Dec 2016

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