Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Early Americans faced rapid late Pleistocene climate change and chaotic environments

20.02.2006


The environment encountered when the first people emigrated into the New World was variable and ever-changing, according to a Penn State geologist.



"The New World was not a nice quiet place when humans came," says Dr. Russell Graham, associate professor of geology and director of the Earth & Mineral Sciences Museum.

Archaeologists agree that by 11,000 years ago, people were spread across North and South America, but evidence is building for an earlier entry into the New World, a date that would put human population of North and South America firmly in the Pleistocene.


"We want to know what it was like back then," says Graham. "What did they have to deal with?"

The Pleistocene Holocene transition took place about 11,000 years ago and caused the extinction of a large number of animal species including mammoths, mastodons and ground sloths. The Holocene looked very different from the Pleistocene.

"We now realize that climate changes extremely rapidly," Graham told attendees at the annual meeting of the American Association for the Advancement of Science today (Feb.19) in St. Louis, Mo. "The Pleistocene to Holocene transition occurred in about 40 years."

As a result, animals and plants shifted around and the people living in the New World had to adapt so that they could find the necessary resources to survive. Graham likened the change to the difference between shopping at a WalMart where there is great abundance and large variety – the Pleistocene – to suddenly having to shop at a corner convenience store – the Holocene. In human terms this means that what grandparents knew to be true about finding resources, could be untrue and not helpful to grandchildren.

During the Pleistocene large eastern coastal resources existed, including walruses, south, as far as Virginia, seals and a variety of fish. Mammoth, caribou and mastodons were plentiful across the continent as well as smaller animals. The situation was not identical in all places across North America because, during segments of the Pleistocene, large portions of the Eastern North American continent were covered in ice, while western locations were ice free much further north.

"The Holocene climate is much more stable than the Pleistocene – warmer but more stable," says Graham. "The environment, however, became more homogeneous, there was less variety."

Graham argues that the Pleistocene experienced a series of rapid climate changes that created patchiness in the environment, but that once the climate change that signaled the beginning of the Holocene occurred, the climate settled down. Humans coming into the New World during the late Pleistocene would have encountered an environment shaped by rapid changes creating variety in available food sources both animal and vegetable. The groups of people would have to adapt continually and find new resources, but the variety of resources was out there. After the Holocene took hold, there was less need to adapt constantly, but also fewer options in resources.

Archaeologists and geologists debate whether the climate change at the Pleistocene Holocene transition caused the extinction of the mega fauna or if the influx of humans did in the large animals. Graham believes that it was the unstable changing rapidly changing climate, not human predation that killed the large Pleistocene animals.

A’ndrea Elyse Messer | EurekAlert!
Further information:
http://www.psu.edu

More articles from Earth Sciences:

nachricht Fossil coral reefs show sea level rose in bursts during last warming
19.10.2017 | Rice University

nachricht NASA finds newly formed tropical storm lan over open waters
17.10.2017 | NASA/Goddard Space Flight Center

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Electrode materials from the microwave oven

19.10.2017 | Materials Sciences

New material for digital memories of the future

19.10.2017 | Materials Sciences

Physics boosts artificial intelligence methods

19.10.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>