Taxonomy term

paleoclimate

Arctic megafauna thrived on pollen-poor plants

Ancient changes in vegetation have traditionally been studied based on fossil pollen; however, this record tends to be biased toward plants that produce lots of pollen, such as grasses, reeds and sedges. Now, researchers have sequenced plant DNA retrieved from radiocarbon-dated permafrost samples and gained further insight into the Arctic plant communities not readily identifiable by pollen analysis.
 

24 Jun 2014

Environmental changes contributed to Mediterranean cultural crisis

About 3,200 years ago, urban cultures thrived in the Eastern Mediterranean until invasions in coastal and inland areas, compounded by agricultural decline, created a regional crisis.

13 Sep 2013

Volcanoes sparked - and prolonged - the Little Ice Age

In the winter of 1780, New York Harbor froze, allowing people to walk from Manhattan to Staten Island for the first time in recorded history. The deep freeze didn’t just occur in New York: For close to 500 years, beginning around the end of the Middle Ages and lasting into the early 19th century, unusually cold conditions blanketed much of the Northern Hemisphere.

08 May 2012

Why red leaves remain elusive in Europe

As leaves change color every fall, the North American landscape transforms from a rolling verdure to a collage of vibrant yellows, oranges and reds. The autumn foliage in Europe, however, is rather bland, composed of mostly yellow leaves with red-leafed trees few and far between. Why this is the case has remained a mystery for years. But discovering why Europe’s leaves don’t turn red is only half of the battle; determining why the trees’ leaves turn yellow in the first place is the other.

03 Nov 2009

Comet finished off North American big game animals, cooled the planet?

Fires from a comet shower may have killed off the big game in North America about 13,000 years ago, scientists say. Those extinctions have long been attributed either to an abrupt return to glaciation known as the Younger Dryas event or to over-hunting. But now, a team of scientists has found tiny, nanoparticle-sized diamonds in sediments from the Younger Dryas — signs that a cosmic impact may have ultimately been behind both the cold period and the extinctions.

02 Jan 2009

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