Watching new species evolve in real time

Sometimes evolution proceeds much more rapidly than we might think. Genetic analysis makes it possible to detect the earliest stages of species formation and to gain a better understanding of speciation processes. For example, a study just published in PLOS Genetics by researchers from Eawag and the University of Bern - investigating rapid speciation in threespine stickleback in and around Lake Constance - shows that a species can begin to diverge very rapidly, even when the two daughter species breed alongside one another simultaneously.

The innumerable three-spined stickleback which end up in fishermen's nets on Lake Constance are an unwanted by-catch. Unlike some other species, these tiddlers - of no commercial value - appear to be relatively unaffected by lake eutrophication, bank stabilization and channelization. This species has been spreading rapidly throughout the Swiss Central Plateau for around 150 years. Now, an elaborate genetic study conducted by researchers at Eawag and Bern University helps to explain the secret of its success: the stickleback can evidently adapt very rapidly to new habitats - so rapidly that, for evolutionary biologists, it serves as a model for the divergence of a single species into two or more distinct species. Rather than just one "Lake Constance stickleback", the researchers found two different forms - typical of the lake and of inflowing streams - even though lake stickleback migrate into these streams during the spawning season.

According to first author David Marques, "It was completely unexpected for the species to diverge over such a short period, given that the sticklebacks breed at the same time and at the same sites." Usually, independent species develop by adapting to different habitats and reproducing isolated from other populations - at different depths of a lake, for example. Among whitefish, different breeding and spawning seasons have additionally evolved.

###

FINANCIAL DISCLOSURE: This research was supported by the Swiss National Science Foundation (http://www.snf.ch) grant PDFMP3_134657 to OS and LE. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

COMPETING INTERESTS: The authors have declared that no competing interests exist.

CITATION: Marques DA, Lucek K, Meier JI, Mwaiko S, Wagner CE, Excoffier L, et al. (2016) Genomics of Rapid Incipient Speciation in Sympatric Threespine Stickleback. PLoS Genet 12(2): e1005887. doi:10.1371/journal.pgen.1005887

PLEASE ADD THIS LINK TO THE FREELY AVAILABLE ARTICLE IN ONLINE VERSIONS OF YOUR REPORT (the link will go live when the embargo ends): http://www.plosgenetics.org/doi/pgen.1005887

Disclaimer

This press release refers to an upcoming article in PLOS Genetics. The release is provided by journal staff, or by the article authors and/or their institutions. Any opinions expressed in this release or article are the personal views of the journal staff and/or article contributors, and do not necessarily represent the views or policies of PLOS. PLOS expressly disclaims any and all warranties and liability in connection with the information found in the releases and articles and your use of such information.

PLOS Genetics reflects the full breadth and interdisciplinary nature of genetics and genomics research by publishing outstanding original contributions in all areas of biology. We publish human studies, as well as research on model organisms--from mice and flies, to plants and bacteria. Our emphasis is on studies of broad interest that provide significant insight into a biological process or processes. Topics include (but are not limited to) gene discovery and function, population genetics, genome projects, comparative and functional genomics, medical genetics, disease biology, evolution, gene expression, complex traits, chromosome biology, and epigenetics.

PLOS is a nonprofit publisher and advocacy organization founded to accelerate progress in science and medicine by leading a transformation in research communication. For more information, visit http://www.plos.org.