The study is the first to demonstrate that the indicator species may adapt to polluted conditions of a habitat and become an entirely unreliable source of information about ecosystem health.
Gary Wellborn, professor of biology in the OU College of Arts and Sciences and director of the Oklahoma Biological Station; Donald P. Weston, University of California, Berkeley; and Helen C. Poyton, University of Massachusetts, Boston; tested cultures in the laboratory and water samples from California lakes, ponds and streams. The Hyalella amphipods are aquatic crustaceans commonly used by scientists and agencies as an indicator species of a healthy, unpolluted environment.
"Our study documented the specific genetic changes that allow the amphipods to survive at 500-times the normal lethal dose of the pesticide," says Wellborn. "The results have far-reaching implications for biomonitoring programs that rely on H. azteca as a bioindicator. H. azteca, a species common across North America, may prove to be an unreliable indicator in other agricultural states where biomonitoring programs use H. azteca as a principal species for monitoring and environmental policy decisions."
Insecticides for agricultural crops are regulated by the Environmental Protection Agency, but runoff during rains can enter a lake, pond or stream and contaminate a non-target species, like H. azteca. The evolution of H. azteca in this study occurred when the species mutated and adapted to the widely used pyrethroid insecticides—a principle known as adaptive evolution. As reported in this study, the resistant H. azteca was no longer reliable as a bioindicator when used to test the toxicity of water and sediment.
A technical article on this study was published in the October 8, 2013 issue of the Proceedings of the National Academy of Sciences. For more information about this study, please contact Gary Wellborn at firstname.lastname@example.org.
Jana Smith | EurekAlert!
Water forms 'spine of hydration' around DNA, group finds
26.05.2017 | Cornell University
How herpesviruses win the footrace against the immune system
26.05.2017 | Helmholtz-Zentrum für Infektionsforschung
Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.
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Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.
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Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
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