Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Texas A&M professor helping to unravel causes of Ice Age extinctions

03.11.2011
Did climate change or humans cause the extinctions of the large-bodied Ice Age mammals (commonly called megafauna) such as the woolly rhinoceros and woolly mammoth?

Scientists have for years debated the reasons behind the Ice Age mass extinctions, which caused the loss of a third of the large mammals in Eurasia and two thirds of the large mammals in North America, and now, an inter-disciplinary team from more than 40 universities around the world led by Professor Eske Willerslev and his group from the Centre for GeoGenetics, University of Copenhagen, have tried to answer the contentious question in one of the biggest studies of its kind ever.

The study by the team, which includes two Texas A&M University professors, is published online today in the journal Nature and reveals dramatically different responses of Ice Age species to climate change and human impact. Using ancient DNA, species distribution models and the human fossil record, the findings indicate that neither climate nor humans alone can account for the Ice Age mass extinctions.

"Our findings put a final end to the single-cause theories of these extinctions," says Willserslev. "Our data suggest care should be taken in making generalizations regarding past and present species extinctions; the relative impacts of climate change and human encroachment on species extinctions really depend on which species we're looking at."

The study reports that climate alone caused extinctions of woolly rhinoceros and musk ox in Eurasia, but a combination of climate and humans played a part in the loss of bison in Siberia and wild horse. While the reindeer remain relatively unaffected by any of these factors, the reasons causes of the extinction of the mammoth remain unresolved.

The study also reports that climate change has been intrinsically linked with major population size changes over the past 50,000 years, supporting the view that populations of many species will decline in the future owing to climate change and habitat loss. Finally, the authors find no clear pattern in their data distinguishing species that went extinct from species that survived.

Eline Lorenzen, professor at the University of Copenhagen and lead author of the study, said, "The fact that we couldn't pinpoint what patterns characterize extinct species - despite the large and varying amount of data analyzed - suggests that it will be challenging for experts to predict how existing mammals will respond to future global climate change. Which species will go extinct and which will survive?

"The bottom line is that we really don't know why some of these ancient species became extinct," adds Ted Goebel, researcher in the Department of Anthropology at Texas A&M and affiliated with the Center for the Study of First Americans.

"Now we can better predict what might happen to animals in the future as climate change occurs. What happens to species when their ranges are significantly diminished, and why do some animals adapt successfully while others become extinct? We now have a genetic roadmap to follow in our efforts to protect sensitive animal populations - especially in drastically impacted regions like the Arctic."

openhagen Contacts

Prof. Director Eske Willerslev
Centre for GeoGenetics
University of Copenhagen
Øster Voldgade 5-7DK-1350, Denmark
Phone: 45-35321309/ 45-28751309
E-mail: ewillerslev@gmail.com
ewillerslev@snm.ku.dk,
http://geogenetics.ku.dk/
Dr. Eline Lorenzen
Centre for GeoGenetics
University of Copenhagen
Oester Voldgade 5-7 DK-1350,
Denmark Office: 45-35-321225
Mobile: 45-26-701024
Email: elinelorenzen@gmail.com
edlorenzen@snm.ku.dk
Texas A&M Contact
Keith Randall
News & Information Services
979-845-4644
keith-randall@tamu.edu
Ted Goebel
Department of Anthropology
979-862-4544
goebel@tamu.edu
About Research at Texas A&M University: As one of the world's leading research institutions, Texas A&M is in the vanguard in making significant contributions to the storehouse of knowledge, including that of science and technology. Research conducted at Texas A&M represents an annual investment of more than $630 million, which ranks third nationally for universities without a medical school, and underwrites approximately 3,500 sponsored projects. That research creates new knowledge that provides basic, fundamental and applied contributions resulting in many cases in economic benefits to the state, nation and world.

Keith Randall | EurekAlert!
Further information:
http://www.tamu.edu

More articles from Earth Sciences:

nachricht Shrinking of Greenland's glaciers began accelerating in 2000, research finds
12.12.2019 | Ohio State University

nachricht One-third of recent global methane increase comes from tropical Africa
11.12.2019 | European Geosciences Union

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Virus multiplication in 3D

Vaccinia viruses serve as a vaccine against human smallpox and as the basis of new cancer therapies. Two studies now provide fascinating insights into their unusual propagation strategy at the atomic level.

For viruses to multiply, they usually need the support of the cells they infect. In many cases, only in their host’s nucleus can they find the machines,...

Im Focus: Cheers! Maxwell's electromagnetism extended to smaller scales

More than one hundred and fifty years have passed since the publication of James Clerk Maxwell's "A Dynamical Theory of the Electromagnetic Field" (1865). What would our lives be without this publication?

It is difficult to imagine, as this treatise revolutionized our fundamental understanding of electric fields, magnetic fields, and light. The twenty original...

Im Focus: Highly charged ion paves the way towards new physics

In a joint experimental and theoretical work performed at the Heidelberg Max Planck Institute for Nuclear Physics, an international team of physicists detected for the first time an orbital crossing in the highly charged ion Pr⁹⁺. Optical spectra were recorded employing an electron beam ion trap and analysed with the aid of atomic structure calculations. A proposed nHz-wide transition has been identified and its energy was determined with high precision. Theory predicts a very high sensitivity to new physics and extremely low susceptibility to external perturbations for this “clock line” making it a unique candidate for proposed precision studies.

Laser spectroscopy of neutral atoms and singly charged ions has reached astonishing precision by merit of a chain of technological advances during the past...

Im Focus: Ultrafast stimulated emission microscopy of single nanocrystals in Science

The ability to investigate the dynamics of single particle at the nano-scale and femtosecond level remained an unfathomed dream for years. It was not until the dawn of the 21st century that nanotechnology and femtoscience gradually merged together and the first ultrafast microscopy of individual quantum dots (QDs) and molecules was accomplished.

Ultrafast microscopy studies entirely rely on detecting nanoparticles or single molecules with luminescence techniques, which require efficient emitters to...

Im Focus: How to induce magnetism in graphene

Graphene, a two-dimensional structure made of carbon, is a material with excellent mechanical, electronic and optical properties. However, it did not seem suitable for magnetic applications. Together with international partners, Empa researchers have now succeeded in synthesizing a unique nanographene predicted in the 1970s, which conclusively demonstrates that carbon in very specific forms has magnetic properties that could permit future spintronic applications. The results have just been published in the renowned journal Nature Nanotechnology.

Depending on the shape and orientation of their edges, graphene nanostructures (also known as nanographenes) can have very different properties – for example,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

The Future of Work

03.12.2019 | Event News

First International Conference on Agrophotovoltaics in August 2020

15.11.2019 | Event News

Laser Symposium on Electromobility in Aachen: trends for the mobility revolution

15.11.2019 | Event News

 
Latest News

New yeast species discovered in Braunschweig, Germany

13.12.2019 | Life Sciences

Hubble watches interstellar comet Borisov speed past the sun

13.12.2019 | Physics and Astronomy

Saliva test shows promise for earlier and easier detection of mouth and throat cancer

13.12.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>