Radiation causes oxidative stress, damages biological molecules and may have "important" negative effects on organisms in relatively high doses, like those found in certain zones close to Chernobyl.
Bird populations fell as the levels of radiation in peripheral zones of Chernobyl (Ukraine) rose. Credit: Rafael Palomo Santana
"In the case of the birds studied, these effects were seen in the size of their populations", says Ismael Galván, lead author of the study and researcher in the Laboratory of Ecology, Systematics and Evolution at the University of Paris-Sur, in France, speaking to SINC.
According to the study, which has been published in the journal Oecologia, bird populations fell as the levels of radiation in peripheral zones of Chernobyl (Ukraine) rose. In total, the researchers analysed the abundance of 97 bird species exposed to different levels of radiation during four years.
In the majority of the birds (64 species), the populations diminished with the level or radioactivity. "Nevertheless, the populations of a few species (the 33 remaining species) experienced positive effects from the radiation (though the magnitude of these effects was very low in some cases), perhaps due to the reduction in competition with other species", explains Galván.
Colour: a bird's weak or strong point
The scientists concentrated on the colouring generated by melanins – pigments which protect from ultraviolet radiation and generate camouflage patterns – of the nearly one hundred species of bird studied. The reason: the type of pigmentation may interfere with the ability to resist radioactivity's negative effects.
"The impact on the populations depends, at least in part, on the amount of plumage whose colouring is generated by pheomelanin, one of the two main types of melanins, which produces orangish and brownish colours", the Spanish expert adds.
The birds of Chernobyl with the most pheomelanism (with the most plumage coloured by pheomelanin) were judged to be the "most negatively" affected by the radioactivity. As the pigment consumes glutathione (one of the antioxidants most susceptible to radiation and whose level tends to be diminished by its effects), in these birds, the capacity to combat the oxidative stress generated by radiation "probably" diminishes.
Galván, Ismael; Mousseau, Timothy A.; Moller, Anders P. "Bird population declines due to radiation exposure at Chernobyl are stronger in species with pheomelanin-based coloration" Oecologia 165(4): 827-835, april of 2011.
SINC Team | EurekAlert!
Value from wastewater
16.08.2017 | Hochschule Landshut
Species Richness – a false friend? Scientists want to improve biodiversity assessments
01.08.2017 | Carl von Ossietzky-Universität Oldenburg
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,...
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...
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...
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...
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...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
18.08.2017 | Life Sciences
18.08.2017 | Physics and Astronomy
18.08.2017 | Materials Sciences