Press Releases
Someone tell the Red Queen: new species arise due to random events, not due to natural selection! – University of Reading
Release Date : 10 December 2009
Research from the University of Reading has found that the mechanism by which new species arise is probably not due to natural selection, but is caused by random events. These findings, published in the Journal Nature, provide a new interpretation of the Red Queen hypothesis, which is based on natural selection, and has previously been used to describe rates of occurrence of new species.
The research shows that collections of closely-related species produce new species (speciation) at a constant rate over millions of years; with new species appearing at random intervals over long periods of time. The difference between this and other views of speciation is that these new findings separate actual speciation events from the gradual changes caused by natural selection.
This model of why new species appear suggests that rare random events happen to species, and that these cause reproductive isolation. These random events could be a number of things, ranging from changes to the environment, to changes in mating preferences, to genetic changes. The reproductive isolation these random events cause prevents the successful mixing of genetic material with individuals outside the isolated group, and hence create a new species.
Professor Mark Pagel from the School of Biological Sciences said “We think this research can transform our understanding of how speciation occurs. Our research indicates that the idea that new species occur by gradually becoming more and more adapted to their particular niches, is not true. In fact, we have found that new species appear due to rare random events that seem to simply just happen.”
The research could explain such things as why there are more than sixteen mouse lemur species in Madagascar that appear to be identical, or why there are so-called living fossils, and why some groups include so many more species than others.
Currently, the main theory used to describe the rates of speciation is known as the Red Queen hypothesis, originally proposed by Leigh Van Valen in 1973. This is a view of nature in which species continually evolve but do not become better adapted because the environment is continually changing. The Red Queen hypothesis describes speciation as a constant race against a constantly changing environment in which "It takes all the running you can do, to keep in the same place". In this hypothesis, over long periods of time a species accumulates enough changes that it becomes a new species.
Scientists at the University of Reading have now tested the claims that the Red Queen hypothesis makes about speciation occurring at a constant rate. Evolutionary biologist Professor Mark Pagel and colleagues used phylogenetic and statistical techniques to rigorously test the Red Queen hypothesis against other models of speciation.
ENDS
Notes to editors
For more information please contact the University of Reading Press Office, on +44 (0)118 378 7388 or media@reading.ac.uk.
This research “Phylogenies reveal new interpretation of speciation and the Red Queen” is published in the journal Nature. The paper will be available online at www.nature.com from 09/12/09 18:00hr, and the digital object identifier (DOI) number will be: 10.1038/nature08630. The DOI can be used to retrieve the abstract and full text from the Nature web site (abstracts are available to everyone, full text only to subscribers) at the following URL: http://dx.doi.org/ . Copies of the full text will be available from the University of Reading communications office on request.
This research was supported by grants from the Natural Environment Research Council (NERC), and the Leverhulme Trust.
The analysis was carried out on 101 phylogenies of animal, plant and fungal taxa. The data sets used included bumblebees, cats, turtles and roses.
The term ‘Red Queen Hypothesis’ was originally taken from the Red Queen's race in Lewis Carroll's book ‘Through the Looking-Glass’. In the story, the Red Queen said, "It takes all the running you can do, to keep in the same place." This hypothesis has originally proposed by Leigh Van Valen in 1973 (Leigh Van Valen. 1973. A new evolutionary law. Evolutionary Theory 1: 1—30).
University of Reading:
The University of Reading is rated as one of the top 200 universities in the world (THE-QS World Rankings 2009).
The University of Reading is one of the UK’s top research-intensive universities. The University is ranked in the top 20 UK higher education institutions in securing research council grants worth nearly £10 million from EPSRC, ESRC, MRC, NERC, AHRC and BBSRC. In the RAE 2008, over 87% of the university’s research was deemed to be of international standing. Areas of particular research strength recognised include meteorology and climate change, typography and graphic design, archaeology, philosophy, food biosciences, construction management, real estate and planning, as well as law.
Standards of teaching are excellent - the University scored highly in the National Student Survey 2009. 87% of Reading students responding to the survey stated they were satisfied with the quality of their course.
The University is estimated to contribute £600 million to the local economy annually.
University of Reading is a member of the 1994 Group of 19 leading research-intensive universities. The Group was established in 1994 to promote excellence in university research and teaching. Each member undertakes diverse and high-quality research, while ensuring excellent levels of teaching and student experience. www.1994group.ac.uk
More information at www.reading.ac.uk