Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Larger nuts end up further from tree

14.02.2003


The acouchy is the most important disperser of nuts in the rainforest of French Guyana


Cameras were one of the devices used by biologists from Wageningen to study nut dispersal


Trees are better off if they produce large nuts. This is revealed in research by Patrick Jansen from Wageningen University. Scatterhoarding rodents appear to prefer burying larger nuts for later. The bigger the nut, the further it is buried from the tree and the more frequently it is forgotten.

Biologist Patrick Jansen investigated what happened to nuts as soon as they fell on the ground of the rainforest in French Guyana. He placed thousands of nuts on the ground in the forest. Each nut was marked with a numbered fluorescent thread. Using video cameras he observed which animals removed the nuts. He then traced the nuts using the threads sticking out of the ground and followed them until they were either eaten or grew into a seedling.

He found that the vast majority of nuts were taken by acouchies, large guinea-pig-like rodents, which are active during the day. These animals mostly use the nuts for their food store. Each nut is buried separately at a different location in the forest soil.



The rodents were found to be fussy. Larger nuts have a far greater chance of being successfully dispersed than smaller ones, as they are buried more frequently and further away. Sometimes they are buried as far as 100 metres away from the tree. The rodents often forget such nuts and therefore these can successfully germinate.

The scientist concluded, partly on the basis of other aspects of his research, that nut-producing trees may have evolved due to the fussiness of the hoarding animals. Trees which produce large nuts obtain many offspring. Over the course of time the number of trees producing large nuts increases and the number producing small nuts decreases.

According to the biologist, protecting animals in managed forests is important for tree regeneration. That has hardly happened up until now. For example, once logging has taken place the tracks for this are used by hunters who are after rodents and other important seed dispersers.

Nalinie Moerlie | alfa
Further information:
http://www.nwo.nl

More articles from Life Sciences:

nachricht World’s Largest Study on Allergic Rhinitis Reveals new Risk Genes
17.07.2018 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht Plant mothers talk to their embryos via the hormone auxin
17.07.2018 | Institute of Science and Technology Austria

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Microscopic trampoline may help create networks of quantum computers

17.07.2018 | Information Technology

In borophene, boundaries are no barrier

17.07.2018 | Materials Sciences

The role of Sodium for the Enhancement of Solar Cells

17.07.2018 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>