Hydroelectric schemes usually generate a barrage of criticism from conservationists. But the flooding of a Venezuelan valley 20 years ago has provided ecologists with the ideal outdoor laboratory to answer one of ecologys oldest and thorniest questions: why is the world green?
Reporting their results in the March issue of the British Ecological Societys Journal of Ecology, a team lead by Professor John Terborgh of Duke University says that the role of predators is the key to keeping the world green, because they keep the numbers of plant-eating herbivores under control. Their results support the so-called “green world hypothesis” first proposed in 1960 by Hairston, Smith and Slobodkin and seem to lay to rest the competing theory that plants protect themselves from being eaten through the physical and chemical defences they have developed.
Despite being nearly 50 years old, the green world hypothesis has been almost impossible to test until now. According to Terborgh: “Since the landmark paper by Hairston et al, ecologists have been debating whether herbivores are limited by plant defences or by predators. The matter is trivially simple in principle, but in practice the challenge of experimentally creating predator-free environments in which herbivores can increase without constraint has proven almost insurmountable.”
Becky Allen | alfa
Dispersal of Fish Eggs by Water Birds – Just a Myth?
19.02.2018 | Universität Basel
Removing fossil fuel subsidies will not reduce CO2 emissions as much as hoped
08.02.2018 | International Institute for Applied Systems Analysis (IIASA)
University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.
Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.
Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.
Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...
Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.
The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...
Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.
Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...
In the fight against cancer, scientists are developing new drugs to hit tumor cells at so far unused weak points. Such a “sore spot” is the protein complex...
13.04.2018 | Event News
12.04.2018 | Event News
09.04.2018 | Event News
20.04.2018 | Physics and Astronomy
20.04.2018 | Interdisciplinary Research
20.04.2018 | Physics and Astronomy