Featured Research

from universities, journals, and other organizations

Math experts question key ecological theory

Date:
June 20, 2012
Source:
University of York
Summary:
Mathematicians say they have disproved a widely accepted theory underpinning the operation of complex networks of interactions in the natural world.

Mathematicians at the University of York in the UK and the University of Canterbury in New Zealand say they have disproved a widely accepted theory underpinning the operation of complex networks of interactions in the natural world.

Related Articles


Networks are a powerful way to describe ecological communities, which typically involve large numbers of species that can exhibit both negative (e.g. competition or predation) and positive (e.g. mutualism) interactions with one another. Recent mathematical and computational analysis suggested that nestedness -- the tendency for ecological specialists to interact with a subset of the species that also interact with more generalist species -- increases species richness.

But the researchers from the York Centre for Complex Systems Analysis (YCCSA) and the Biomathematics Research Centre at Canterbury say they have proved the reverse is true, using mathematical models based on plant-pollinator networks observed in the wild. The data span the globe, ranging from tropical rainforests to the high Arctic, and include species such as birds of paradise and hummingbirds as well as insect pollinators such as bees, wasps and butterflies.

The research is published in the latest edition of Nature.

By carefully examining previous analytic results, and applying computational and statistical methods to 59 empirical datasets representing mutualistic plant-pollinator networks, they say they disprove the accepted theory of nestedness. Instead, they contend that the number of mutualistic partners a species has is a much better predictor of individual species survival and community persistence.

Co-author Dr Jon Pitchford, who is also a member of the Departments of Biology and Mathematics at York, said: "We know that real mutualistic communities are nested -- they have sets of interactions-within-interactions, rather like Russian dolls. We are trying to understand how this is related to their biodiversity and stability. This will enable us to better understand the way ecological networks are affected by environmental fluctuation and climate change."

Co-author Dr Alex James, of the Department of Mathematics and Statistics at Canterbury, said: "It is a well-used phrase but correlation does not imply causation. Although a cursory glance at real networks can make it appear that nestedness is correlated with survival, you need to delve deeper to realise this is a secondary correlation. The stronger and more causal relationship is between the number of mutualistic partners a species has and its survival."

Co-author Dr Michael Plank, also of the Department of Mathematics and Statistics at Canterbury, added: "Real-life networks, whether they are from ecology, economics, or Facebook, can be large and complex. This makes it difficult to tease apart causal relationships from confounding factors. This is where mathematical models come into their own. They allow us to systematically change one network attribute, such as nestedness, whilst controlling for other variables."


Story Source:

The above story is based on materials provided by University of York. Note: Materials may be edited for content and length.


Journal Reference:

  1. Alex James, Jonathan W. Pitchford, Michael J. Plank. Disentangling nestedness from models of ecological complexity. Nature, 2012; DOI: 10.1038/nature11214

Cite This Page:

University of York. "Math experts question key ecological theory." ScienceDaily. ScienceDaily, 20 June 2012. <www.sciencedaily.com/releases/2012/06/120620133157.htm>.
University of York. (2012, June 20). Math experts question key ecological theory. ScienceDaily. Retrieved February 28, 2015 from www.sciencedaily.com/releases/2012/06/120620133157.htm
University of York. "Math experts question key ecological theory." ScienceDaily. www.sciencedaily.com/releases/2012/06/120620133157.htm (accessed February 28, 2015).

Share This


More From ScienceDaily



More Plants & Animals News

Saturday, February 28, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Whale-Watching Scientists Spot Baby Orca

Whale-Watching Scientists Spot Baby Orca

AP (Feb. 28, 2015) Researchers following endangered killer whales spotted a baby orca off the coast of Washington state, the third birth documented this winter but still leaving the population dangerously low. (Feb. 28) Video provided by AP
Powered by NewsLook.com
The Best Drinks for Your Health

The Best Drinks for Your Health

Buzz60 (Feb. 27, 2015) When it comes to health and fitness, there&apos;s lots of talk about what foods to eat, but there are a few liquids that can promote good nutrition. Krystin Goodwin (@krystingoodwin) has the healthiest drinks to boost your health! Video provided by Buzz60
Powered by NewsLook.com
Cherries, Snap Peas and More Tasty Spring Produce

Cherries, Snap Peas and More Tasty Spring Produce

Buzz60 (Feb. 27, 2015) From sweet cherries to sugar snap peas, spring is the peak season for some of the tastiest and healthiest produce. Krystin Goodwin (@Krystingoodwin) has the best seasonal fruits and veggies to spring in to good health! Video provided by Buzz60
Powered by NewsLook.com
The Best Foods to Battle Stress

The Best Foods to Battle Stress

Buzz60 (Feb. 26, 2015) If you&apos;re dealing with anxiety, there are a few foods that can help. Krystin Goodwin (@krystingoodwin) has the best foods to tame stress. Video provided by Buzz60
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:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

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