Featured Research

from universities, journals, and other organizations

Understanding the past and predicting the future by looking across space and time

Date:
May 25, 2013
Source:
University of Wisconsin-Madison
Summary:
Scientists have validated a fundamental assumption at the very heart of a popular way to predict relationships between complex variables.

Studying complex systems like ecosystems can get messy, especially when trying to predict how they interact with other big unknowns like climate change.
Credit: arquiplay77 / Fotolia

Studying complex systems like ecosystems can get messy, especially when trying to predict how they interact with other big unknowns like climate change.

In a new paper published this week (May 20) in the Proceedings of the National Academy of Sciences, researchers from the University of Wisconsin-Madison and elsewhere validate a fundamental assumption at the very heart of a popular way to predict relationships between complex variables.

To model how climate changes may impact biodiversity, researchers like Jessica Blois and John W. (Jack) Williams routinely use an approach called "space-for-time substitution." The idea behind this method is to use the information in current geographic distributions of species to build a model that can predict climate-driven ecological changes in the past or future. But does it really work?

"It's a necessary assumption, but it's generally untested," says lead study author Blois, a former postdoctoral fellow with Williams at UW-Madison. She is now an assistant professor at the University of California, Merced. "Yet we're using this every day when we make predictions about biodiversity going into the future with climate change."

Their results should give other ecologists -- and potentially others such as economists who use similar models -- more confidence in their methods.

"At these spatial and temporal scales, the space-for-time assumption does work well," says Williams, professor of geography and director of the Center for Climatic Research at the UW-Madison Nelson Institute for Environmental Studies. "Our fossil data did support the idea that you can use spatial relationships as a source of information for making these predictions for the future."

Their research focus is paleoecology, the study of ancient ecosystems. By looking at fossilized pollen trapped in cores of sediment from the bottoms of lakes, the scientists reconstructed information about the plant communities present at locations across eastern North America during the past 21,000 years.

If climate has influenced communities the same way across space and through time, Blois explains, then a model based on the spatial data should make the same predictions as a model based on their temporal data. And in fact, they did.

The space-for-time model explained about 72 percent of the variation seen in their time data, and the remainder is likely due to other biological and environmental factors that the simplified model does not include, Blois says.

Though the testing does not capture all the ways space-for-time substitutions are used in other predictive fields, she says that the results are very encouraging for questions spanning large geographic and time scales -- scales at which collecting good temporal data can be very challenging.

"We found that at these broad time scales we're looking at, that space does substitute for time relatively well," Blois says. "It makes me more confident in my analyses going forward."


Story Source:

The above story is based on materials provided by University of Wisconsin-Madison. The original article was written by Jill Sakai. Note: Materials may be edited for content and length.


Journal Reference:

  1. J. L. Blois, J. W. Williams, M. C. Fitzpatrick, S. T. Jackson, S. Ferrier. Space can substitute for time in predicting climate-change effects on biodiversity. Proceedings of the National Academy of Sciences, 2013; DOI: 10.1073/pnas.1220228110

Cite This Page:

University of Wisconsin-Madison. "Understanding the past and predicting the future by looking across space and time." ScienceDaily. ScienceDaily, 25 May 2013. <www.sciencedaily.com/releases/2013/05/130525143731.htm>.
University of Wisconsin-Madison. (2013, May 25). Understanding the past and predicting the future by looking across space and time. ScienceDaily. Retrieved August 20, 2014 from www.sciencedaily.com/releases/2013/05/130525143731.htm
University of Wisconsin-Madison. "Understanding the past and predicting the future by looking across space and time." ScienceDaily. www.sciencedaily.com/releases/2013/05/130525143731.htm (accessed August 20, 2014).

Share This




More Fossils & Ruins News

Wednesday, August 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Disquieting Times for Malaysia's 'fish Listeners'

Disquieting Times for Malaysia's 'fish Listeners'

AFP (Aug. 19, 2014) Malaysia's last "fish listeners" -- practitioners of a dying local art of listening underwater to locate their quarry -- try to keep the ancient technique alive in the face of industrial trawling and the depletion of stocks. Duration: 02:29 Video provided by AFP
Powered by NewsLook.com
Mother And Son Find Woolly Mammoth Tusks 22 Years Apart

Mother And Son Find Woolly Mammoth Tusks 22 Years Apart

Newsy (Aug. 15, 2014) A mother and son in Alaska uncovered woolly mammoth tusks in the same river more than two decades apart. Video provided by Newsy
Powered by NewsLook.com
Fossils Reveal Ancient Flying Reptile With 'Butterfly Head'

Fossils Reveal Ancient Flying Reptile With 'Butterfly Head'

Newsy (Aug. 14, 2014) Newly found fossils reveal a previously unknown species of flying reptile with a really weird head, which some say looks like a butterfly. Video provided by Newsy
Powered by NewsLook.com
Clearing WWII's Explosive Legacy in the Pacific

Clearing WWII's Explosive Legacy in the Pacific

AFP (Aug. 11, 2014) The hulks of tanks can still be found rusting in the jungles of Palau, but the fierce fighting that scarred the Pacific island nation in WWII has left a more dangerous legacy - unexploded bombs that pose a constant risk to locals. Duration: 00:47 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins