Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Experimental proof of chaos in food webs

14.02.2008
The traditional idea of the balance of nature has taken quite a beating by a study that appears in the 14 February issue of Nature.

Using a long-term laboratory experiment, the study demonstrates that, even under constant conditions, all species in a food web continued to fluctuate in a chaotic fashion. Chaos makes long-term prediction of species abundances impossible.

Theoretical ecologists already argued in the 1970s that populations of plants and animals might fluctuate in an unpredictable manner, even without external influences. These predictions, derived from chaos theory, attracted a lot of debate. However, only few scientists believed that species in real ecosystems would truly fluctuate in a chaotic fashion. The common perception was that species fluctuations result from changes in external conditions, driven by climate change or other disturbances of the balance of nature.

This classic perspective has been radically changed by new findings of graduate student Elisa Benincà and Professor Jef Huisman of the Institute for Biodiversity and Ecosystem Dynamics of the University of Amsterdam, The Netherlands, in collaboration with colleagues from Wageningen University (The Netherlands), the University of Rostock (Germany), and Cornell University (USA).

The core of their work consists of a laboratory experiment in which a plankton community isolated from the Baltic Sea was studied for more than eight years. The experiment was maintained under constant light and temperature conditions by the German biologist Reinhard Heerkloss, who reported the development of the different plankton species twice a week. To his major surprise, the food web never settled at equilibrium and the species abundances continued to vary wildly. He sent his data to Amsterdam for statistical analysis. This revealed that the fluctuations were caused by the species themselves; competition and predation generated a dynamic food web in which none of the species succeeded in getting the upper hand. Advanced mathematical techniques proved the indisputable presence of chaos in this food web.

According to the authors, these findings have far-reaching implications: “Our results demonstrate that species abundances are essentially unpredictable in the long term. For many years, we thought that a better understanding of all relevant processes would enable sound prediction of changes in species abundances in response to external factors (e.g., climate change). Now we know that things are not as simple as that.” Professors Jef Huisman and Marten Scheffer, both from The Netherlands, had already foreseen the possibility of chaos in plankton communities by means of mathematical models. However, the experimental demonstration of chaos in this study provides the real breakthrough. The limited predictability of species in food webs is comparable to the weather forecast. Benincà: “Short-term prediction is possible, but long-term prediction is not. We can at best indicate within which boundaries species will fluctuate”.

The research was financed by the Earth and Life Sciences Foundation, which is subsidized by the Netherlands Organization for Scientific Research (NWO).

Josje Spinhoven | alfa
Further information:
http://www.uva.nl

More articles from Ecology, The Environment and Conservation:

nachricht Bioinvasion on the rise
15.02.2017 | Universität Konstanz

nachricht Litter Levels in the Depths of the Arctic are On the Rise
10.02.2017 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung

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: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Impacts of mass coral die-off on Indian Ocean reefs revealed

21.02.2017 | Earth Sciences

Novel breast tomosynthesis technique reduces screening recall rate

21.02.2017 | Medical Engineering

Use your Voice – and Smart Homes will “LISTEN”

21.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>