Taxonomy term

ice age

End of ice age may have been too wet for megafauna

Between 15,000 and 11,000 years ago, dozens of ice-age megafauna species went extinct. Various causes, from climate-driven habitat changes to overhunting to extraterrestrial impacts, have been cited for these extinctions. But new research looking at fossils of large herbivores such as bison, horses and llama supports the idea that a worldwide uptick in moisture was a main driver of the extinction trend.

08 Sep 2017

Small floods can carve big canyons

Through the early 20th century, geologists argued over how the giant canyons of the Channeled Scablands in Eastern Washington were formed. Ultimately, a theory proposed by J Harlen Bretz in the 1920s — that the canyons were carved by catastrophic, short-lived outbursts of floodwaters unleashed when natural dams holding back glacial lakes collapsed — was shown to be correct. Controversy still exists, though, about the size of these ancient floods.
 

03 Feb 2017

Cave paintings confirm mystery European bison species

Ice-age hunters had an intimate knowledge of the animals they coexisted with — and this familiarity is clearly depicted in paintings on cave walls throughout Europe. Inside a cave in France, scientists recently identified artistic evidence dating to about 17,000 years ago of a previously unknown hybrid species of cattle crossed with bison. The paintings confirm findings from recent genetic studies of fossil bison, the researchers say.

25 Jan 2017

Comment: Will we eliminate Earth's Ice-Age cycle?

Earth has been ice free before, with warmer temperatures and higher carbon dioxide and sea levels. But humans have only lived on a relatively cold planet. Will we be able to adapt to an ice-free planet? 

11 Jan 2017

Humans, megafauna coexisted in Patagonia before extinction

During the last ice age, giant mammals roamed the wide-open steppes of what is now Patagonia. Around the time that humans were making their way down through North America and into South America, the climate began warming and large species of giant sloths and saber-toothed cats soon disappeared. Now, researchers looking at mitochondrial DNA from some of these megafaunal species are shedding light on the timing of the extinction and whether encroaching humans or changing climate — or both — were to blame for their disappearance.

11 Oct 2016

Ice sheet has had lasting effect on European earthquakes

“Modern Germany is not known for its earthquakes,” says Christian Brandes, a geoscientist at the University of Hannover in Germany. The country, after all, is in the middle of a tectonic plate, he says, away from any plate boundaries or other features that would cause tectonic strain to build up in underground faults. 
 
10 Nov 2015

Southbound icebergs off the hook for ice-age cooling

During the Late Pleistocene, changes in North Atlantic Ocean circulation triggered abrupt changes in global climate: In some locations in the Northern Hemisphere, average temperatures dropped by as much as 10 degrees Celsius within a few decades. Scientists have long thought that freshwater from melting icebergs traveling south from the Arctic may have instigated the circulation shifts that contributed to cooling feedback loops. But now, scientists looking at seafloor sediments collected near Iceland have found that pulses of icebergs typically arrived after the onset of cooling episodes, too late to be primary drivers of climate change.
 
11 Aug 2015

Fieldwork revises ice-free corridor hypothesis of human migration

The existence of an ice-free corridor through Canada during  the climax of last glaciation, which allowed the first Americans to cross the Bering land bridge from Siberia and move south (about 13,000 years ago), has long been postulated in North American archaeology. Now, research based on the exposure ages of glacial rocks found in the corridor suggests a puzzling conclusion — that the open pathway closed several thousand years prior to 20,000 years ago and didn’t open again until between 13,000 and 12,000 years ago, well after  first Americans were in the Americas.

13 Apr 2014

July 28, 1996: Kennewick man is discovered

On the evening of July 28, 1996, archaeologist James Chatters received an unexpected call at his home in Richland, Wash., from the local coroner. Two spectators at the local hydroplane races had found a skull in Columbia Park on the banks of the Columbia River near Kennewick, Wash. The coroner wanted Chatters, a paleontologist and forensic anthropologist affiliated with Central Washington University who often consulted for Benton County, to look at the skull and determine if it belonged to a recent murder victim. When the coroner arrived with the skull in a 5-gallon bucket, Chatters had scant notion that the discovery would end up challenging the reigning theory of the origins of the first Americans and would embroil scientists in a protracted, precedent-setting legal battle against the federal government.

27 Jul 2013

Earliest instrumental temperature record recovered in Italy

 

In the aftermath of the flood that struck Florence, Italy in 1966, records from the national library became scattered, including the earliest known instrumental temperature records collected by the Medicis in the 1600s. Recently, the temperature records were rediscovered and analyzed for the first time, giving researchers new insight into climate during the Little Ice Age. 

10 May 2012