Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Species take care of each other in ecological communities

01.12.2005


Unspoken rules of existence in tropical rain forests mean no one species will take up too much space and squeeze others out, says new research conducted in part at the University of Alberta that shows how ecological communities regulate themselves.



Dr. Fangliang He is part of a research team that studied fundamental questions plaguing scientists since Darwin’s time: why are some species so common while others are rare? How do common and rare species interact? And how do hundreds, even thousands, of tree species coexist in a limited space in the tropics?

He, along with Igor Volkov and Jayanth Banavar, from Pennsylvania State University, Stephen Hubbell from the University of Georgia and Amos Maritan from the Universita di Padova in Italy, offer a new theory to explain why tropical rain forests are so species rich and how species are assembled in a community. Their work is published in the current edition of "Nature".


Species must meet certain conditions to live in a community. Understanding the rules that make up community assemblages is one of the most challenging scientific questions facing scientists today. Niche theory, which assumes species differ from one another in various aspects, has been traditionally used to explain community assemblages. However, this theory offers little to predict community assemblage patterns – the way species share a limited space.

He’s work attempts to address community assembly rules based on Hubbell’s recently developed neutral theory. "The basic idea of the neutral theory is that community membership is determined by five fundamental processes: birth, death, immigration, speciation and random drift. Furthermore, the theory assumes that every individual in the community, regardless of species identity, has the same rates of birth, death, immigration and mutating into a new species," said He, who is a Canada Research Chair from the Department of Renewable Resources.

The research team modified this theory by arguing that the birth rate and mortality rate are not identical across species, but there is a "density-dependent" probability of birth and death. The more abundant species have lower birth rates and higher mortality rates. "The consequence is that when a species becomes rare, its birth rate will increase and death rate will reduce," said He. In other words, species will regulate themselves to make room for each other if they follow the membership rules. "If not, they’re out."

The scientists tested their model using data from six tropical rain forests--these tiny areas can accommodate more than 1000 tree species--across the world. "Our theory offers a better understanding of why tropical rain forests are so species rich," said He. "This rare species advantage regulates dynamics and therefore permits the coexistence of many species

Phoebe Dey | EurekAlert!
Further information:
http://www.ualberta.ca

More articles from Ecology, The Environment and Conservation:

nachricht Value from wastewater
16.08.2017 | Hochschule Landshut

nachricht Species Richness – a false friend? Scientists want to improve biodiversity assessments
01.08.2017 | Carl von Ossietzky-Universität Oldenburg

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: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>