UBC prof’s research challenges prevailing theory of how new species evolve
A research team lead by University of British Columbia zoology assistant professor Darren Irwin is the first in the world to demonstrate a genetic gradient--or path of gradually changing genetic traits--between two distinct species that have been isolated by distance. The research challenges the prevailing theory among evolutionary biologists that species evolve only when separated by a geographical barrier.
The findings, published in the January 21 issue of Science magazine, have broad implications for preserving biological diversity and endangered species, says Irwin. "The process for how one species evolves into two is a subject of intense research interest and debate and is fundamental to understanding diversity of life," says Irwin, who spent ten months between 1994 and 2002 studying greenish warblers in Asia. "Until now, no one has been able to show continuous gene flow between reproductively isolated species via geographically connected populations – a process of evolution called speciation by distance."
Part of the difficulty in proving the theory has been that few examples of such species are known today. The greenish warbler, living throughout Asia, and the Ensatina salamander found in mountains in North Americas west coast, are the only known clear examples of species that may have evolved across distance.
Two distinct forms of greenish warblers co-exist in central Siberia but do not interbreed there, making them distinct species in that region. Irwin, along with co-authors Staffan Bensch (Lund University, Sweden), Jessica Irwin (UBC) and Trevor Price (University of Chicago) used a new genetic analysis technique called amplified fragment length polymorphism (AFLP) to trace a genetic gradient from one Siberian species to the other via a long chain of geographically connected populations to the south, surrounding the Tibetan Plateau.
Irwin believes the findings have broad implications for current approaches to conservation. "Much of endangered species law relies on identifying distinct groups that are reproductively isolated from other groups, and only those distinct groups are targeted for protection," says Irwin. "Our findings show that in some cases there are not well-defined groups, but rather a gradient of forms. In such cases the whole gradient of forms needs to be conserved."
"With massive habitat destruction being caused by humans, these gradients are being destroyed, as are the stories they tell about evolution and biodiversity," says Irwin. "This is happening in much of Asia, where there is a tremendous loss of habitat from humans."
"Ten years from now, Im not sure I would be able to find this same evidence," says Irwin.
Randy Schmidt | EurekAlert!
The most recent press releases about innovation >>>
Die letzten 5 Focus-News des innovations-reports im Überblick:
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.
Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....
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.
The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
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...
Nano-hologram paves way for integration of 3-D holography into everyday electronics
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...