Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Long-term Study Shows Effect of Climate Change on Animal Diversity

24.09.2008
Two species of giraffe, several rhinos and five elephant relatives, along with multitudes of rodents, bush pigs, horses, antelope and apes, once inhabited what is now northern Pakistan.

But when climate shifted dramatically there some 8 million years ago, precipitating a major change in vegetation, most species became locally extinct rather than adapting to the new ecosystem, according to an extensive, long-term study of mammal fossils spanning a 5-million-year period.

Results of the study, by University of Michigan paleoecologist Catherine Badgley and coworkers, are scheduled to be published online in the Proceedings of the National Academy of Sciences the week of Aug. 18.

The work has value not only in reconstructing Earth's past, but also for understanding what may lie ahead if current climate trends continue, Badgley said. "Climate is going to produce changes in ecological structure of all sorts of plants and animals around the world, now as in the past. The fossil record can help us understand how much---or how little---climate change is necessary to produce changes in ecosystems."

Badgley is part of an interdisciplinary team of geologists and paleontologists that has been studying the fossil-rich Siwalik sedimentary rocks in northern Pakistan for more than 30 years. The Siwalik Group of sediments contains one of the world's most complete and best-studied fossil records of mammals, chronicling in a two-mile-thick deposit of rock the mammals that roamed the area from 18 to 1 million years ago. About 8 million years ago, the local climate became drier, and the prevailing vegetation changed from tropical forests and woodland to a savannah similar to that found in parts of Africa today.

What happened next can be reconstructed from the chemistry and wear of the teeth of the plant-eating mammals, as well as the longevity of each species during the period when vegetation was changing. The teeth provide evidence of the animals' diets, revealing whether they switched to eating the newly abundant grasses when their favored fruits and broad-leafed plants were no longer available.

Mammals that relied on fruit and browse disappeared early in the transition from forest to savannah vegetation and were not replaced, while those that ate broad leaves and grasses either adapted and persisted by changing their diets to include more grass or disappeared and were replaced by immigrant species with similar diets. By the time that savannah was the dominant vegetation, most herbivorous mammals in the area subsisted mainly on grass. The overall effect was a significant decline in the diversity of mammals in the area.

"We see quite a different ecological profile of the kinds of mammals that coexisted after this climate change than before," said Badgley, who is an assistant professor of ecology and evolutionary biology, as well as a research scientist in the Department of Geological Sciences and the Museum of Paleontology. "It's clear that climate has had an impact on the ecological diversity of mammals in the area."

In addition to providing compelling evidence for the effects of climate change on ecological systems, the paper is a testament to the value of long-term research in a single field area, Badgley said. "This is the kind of study you can only do after you've been working in a place with a big team for 25 years or more, because you need all the other basic data to be thoroughly resolved before you can even start to address the kinds of questions in this work. We've been fortunate to have a team that found the various research topics so worthwhile and so interesting that they stuck with it for several decades, and we've also been fortunate to receive funding for field work for that long."

Badgley's co-authors on the PNAS paper are John Barry, Michèle Morgan and David Pilbeam of Harvard University; Sherry Nelson of the University of New Mexico; Kay Behrensmeyer of the National Museum of Natural History and Thure Cerling of the University of Utah. The research described in the paper was supported by a grant from the National Science Foundation.

Nancy Ross-Flanigan | Newswise Science News
Further information:
http://www.umich.edu
http://www.pnas.org/
http://www.ns.umich.edu/htdocs/public/experts/ExpDisplay.php?ExpID=1337

More articles from Ecology, The Environment and Conservation:

nachricht 100 % Organic Farming in Bhutan – a Realistic Target?
15.06.2018 | Humboldt-Universität zu Berlin

nachricht What the size distribution of organisms tells us about the energetic efficiency of a lake
05.06.2018 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

Im Focus: Photoexcited graphene puzzle solved

A boost for graphene-based light detectors

Light detection and control lies at the heart of many modern device applications, such as smartphone cameras. Using graphene as a light-sensitive material for...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Carbon nanotube optics provide optical-based quantum cryptography and quantum computing

19.06.2018 | Physics and Astronomy

How to track and trace a protein: Nanosensors monitor intracellular deliveries

19.06.2018 | Life Sciences

New material for splitting water

19.06.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>