Why the big animals went down in the pleistocene-was it just the climate?

November 07, 2001

There wasn't anything special about the climate changes that ended the Pleistocene. They were similar to previous climate changes as recorded in deep sea cores. So what tipped the scale and caused the extinction?

Russell Graham, who has been working on climate models for Pleistocene extinction for almost 30 years, looked for triggers in a threshold effect that did not require a unique climate change. Graham, Chief Curator at the Denver Museum of Nature and Science, will present his research on Wednesday, November 7, at the Geological Society of America's annual meeting in Boston, Massachusetts.

"The end Pleistocene climate change, especially the Younger Dryas [a sudden cold period], was a trigger that tipped the balance," he explained. "Also, the climate model needed to answer the question of why big animals--mammoths, mastodons, ground sloths, etc., were the primary ones to go extinct and not the small ones. The answer to this question is the relationship between geographic range and body size. The larger an animal, the more real estate or geographic range it needs to support viable populations, especially in harsh environments like those of the Pleistocene.... Therefore, if the geographic range of animals decreased through time then their probability of extinction would increase with time."

Graham successfully tested his hypothesis by using a computer database of fossil ice age mammal sites linked with a geographic information system to map changes in the distribution of species throughout time.

"This is one of the first models that does not require a unique climate change at the end of the Pleistocene. To my knowledge it is one of the first to look at geographic range changes of a large number of mammal species as the primary driving factor of the extinction."
-end-
Written by Kara LeBeau, GSA Staff Writer

CONTACT INFORMATION

During the GSA Annual Meeting, November 4-8, contact Ann Cairns or Christa Stratton at the GSA Newsroom in the Hynes Convention Center, Boston, Massachusetts, for assistance and to arrange for interviews: (617) 954-3214.

The abstract for this presentation is available at: http://gsa.confex.com/gsa/2001AM/finalprogram/abstract_17728.htm

Post-meeting contact information:

Russell Graham, Chief Curator
Denver Museum of Nature and Science
2001 Colorado Blvd, Denver, CO 80205
Phone: (303) 370 6073
E-mail: rgraham@dmns.org

Ann Cairns
Director of Communications
Geological Society of America
Phone: 303-357-1056
Fax: 303-357-1074
acairns@geosociety.org

For more information about GSA visit our Web site at: http://www.geosociety.org

Geological Society of America

Related Climate Articles from Brightsurf:

Are climate scientists being too cautious when linking extreme weather to climate change?
Climate science has focused on avoiding false alarms when linking extreme events to climate change.

Climate Insights 2020: Climate opinions unchanged by pandemic, but increasingly entrenched
A new survey provides a snapshot of American opinion on climate change as the nation's public health, economy, and social identity are put to the test.

Climate action goes digital
More transparent and accessible to everyone: information and communication technologies bring opportunities for transforming traditional climate diplomacy.

Sub-national 'climate clubs' could offer key to combating climate change
'Climate clubs' offering membership for sub-national states, in addition to just countries, could speed up progress towards a globally harmonized climate change policy, which in turn offers a way to achieve stronger climate policies in all countries.

Review of Chinese atmospheric science research over the past 70 years: Climate and climate change
Over the past 70 years since the foundation of the People's Republic of China, Chinese scientists have made great contributions to various fields in the research of atmospheric sciences, which attracted worldwide attention.

How aerosols affect our climate
Greenhouse gases may get more attention, but aerosols -- from car exhaust to volcanic eruptions -- also have a major impact on the Earth's climate.

Believing in climate change doesn't mean you are preparing for climate change, study finds
Notre Dame researchers found that although coastal homeowners may perceive a worsening of climate change-related hazards, these attitudes are largely unrelated to a homeowner's expectations of actual home damage.

How trees could save the climate
Around 0.9 billion hectares of land worldwide would be suitable for reforestation, which could ultimately capture two thirds of human-made carbon emissions.

Climate undermined by lobbying
For all the evidence that the benefits of reducing greenhouse gases outweigh the costs of regulation, disturbingly few domestic climate change policies have been enacted around the world so far.

Climate education for kids increases climate concerns for parents
A new study from North Carolina State University finds that educating children about climate change increases their parents' concerns about climate change.

Read More: Climate News and Climate Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.