Guppy Project News
A longstanding problem in ecology is whether structured life cycles impede or facilitate coexistence between species. Theory based on populations with only two discrete stages in the life-cycle indicates that for two species to coexist, at least one must shift its niche between stages and each species must be a better competitor in one of the niches. However, in many cases, niche shifts are associated with changes in an underlying continuous trait like body size and we have few predictions concerning conditions for coexistence for such a widespread form of ontogenetic development. We develop a framework for analyzing species coexistence based on Integral Projection Models (IPMs) that incorporates continuous ontogenetic changes in both the resource niche and competitive ability. We parameterize the model using experimental data from Trinidadian guppies and show how niche shifts and competitive symmetries impact species coexistence. Overall, our results show that the effects of competition on fitness depend upon trait-mediated niche-separation, trait-mediated competitive asymmetry in the part of the niche that is shared across body sizes, and the sensitivity of fitness to body size. Interactions among these processes generate multiple routes to coexistence. We discuss how our modelling framework expands results from two-stage models to mutli-stage or continuous stage models and allows for deriving predictions that can be tested in populations displaying continuous changes in niche use and competitive ability.
7/12/2017 0 Comments
Newish article from the The Scientist. Article can be found here.
An omnibus update on the progress of several former interns:
Congratulations to Troy Simon, past graduate student on the guppy project, on his new paper on guppy phenotype effects in Trinidadian streams. While previous studies have shown that evolutionary divergence alters ecological processes in small-scale experiments, a major challenge is to assess whether such evolutionary effects are important in natural ecosystems at larger spatial scales. At the landscape scale, across eight streams in the Caroni drainage, we found that the presence of locally adapted populations of guppies (Poecilia reticulata) is associated with reduced algal biomass and increased invertebrate biomass, while the opposite trends were true in streams with experimentally introduced populations of non-locally adapted guppies. Exclusion experiments conducted in two separate reaches of a single stream showed that guppies with locally adapted phenotypes significantly reduced algae with no effect on invertebrates, while non-adapted guppies had no effect on algae but significantly reduced invertebrates. These divergent effects of phenotype on stream ecosystems are comparable in strength to the effects of abiotic factors (e.g. light) known to be important drivers of ecosystem condition. They also corroborate the results of previous experiments conducted in artificial streams. Our results demonstrate that local adaptation can produce phenotypes with significantly different effects in natural ecosystems at a landscape scale, within a tropical watershed, despite high variability in abiotic factors: five of the seven physical and chemical parameters measured across the eight study streams varied by more than one order of magnitude. Our findings suggest that ecosystem structure is, in part, an evolutionary product and not simply an ecological pattern.
5/22/2017 0 Comments
12/23/2016 0 Comments
12/23/2016 0 Comments
August 2016. David Reznick prepares to begin his Guggenheim Fellowship.David Reznick will use his Guggenheim Fellowship to spend a year at Oxford University. He aspires to learn something of Integrated Population Models and mixed effects modeling during his time there. We wish him the best of luck for his time abroad!
June 10, 2016. Martin Turcotte gets a new position.Congratulations to former FIBR graduate student Martin Turcotte on becoming a newly minted assistant professor at the University of Pittsburgh. All the best to him in his new environs!
June 10, 2016. Another wave of FIBR alumni enter graduate school.Several former interns have accepted offers to begin graduate school in the upcoming academic year. Kathryn Chenard, former intern and field manager, will join Renée Duckworth's lab at the University of Arizona. Greg Larsen, another former intern and field manager, will begin at Duke University in David Johnston's lab, working on large marine mammals. Greg will bring with him a wealth of experience and an NSF Graduate Research Fellowship. Tomas Potter, former intern, lab manager and experimental ace, has accepted the offer of the Oxford University Doctoral Traineeship Program. While he has not chosen a major professor or study system, he may very well return to Trinidad for his doctoral research. Meanwhile, Toby Hector will begin exploring the Southern Hemisphere as a PhD student in Matthew Hall's lab at Monash University, Melbourne, Australia. Good luck to all in their new academic adventures!
April 6, 2016. David Reznick wins a Guggenheim Fellowship.Congratulations to David Reznick on winning the prestigious John Simon Guggenheim Memorial Foundation Fellowship for 2016! Well done, David! See the announcement in the New York Times.
December 28, 2015. News from the FIBR family treeFormer FIBR intern (2011-2012) extraordinaire Jennifer Hoey has had a successful start to her PhD at Rutgers University. She has been applying genetic techniques to understand population structure, dispersal and connectivity in summer flounder. In the future, she may expand these themes to examine how fishing pressure and climate have influenced adaptation in this species. Best of luck moving forward, Jennifer!
September 21, 2015. New FIBR papers!Two new FIBR papers have been published, one in the journal Oikos and another in Freshwater Biology. Please click on the Publications page to view them!
September 17, 2015. Where are they now? News on FIBR alumni Matthew Walsh, a former graduate student affiliated with FIBR, is now an assistant professor at the University of Texas, Arlington. He has just received a grant from NSF to exploit the long-term data set amassed by a LTER project in Wisconsin to study the evolution of microcrustacea in Wisconsin lakes. There are traces of responses to climate change and other anthropogenic influences on the environment evident in the phenotypes of samples archived over the past 30 years. Matt will extract information from these archived samples and combine it with laboratory experiments that characterize genetic divergence among the extant populations. You can hear an interview of Matt that was featured on NPR at this link: http://www.wpr.org/biologist-gets-national-science-grant-study-environmental-change-wisconsin-lakes
September 2015. Science News articleThe September 2015 Nature paper by Ghalambor et. al was featured in a Science News article, "Unhelpful adaptations can speed up evolution." Visit http://cnas.ucr.edu/guppy/fibrsciencenews.pdf to download the article.
September 2, 2015. Nature paper press releasesA paper published on 2 September 2015 in Nature by Ghalambor and colleagues has been featured in several press releases:
Featured press release entry:
Evolutionary biology: How guppy fish adapt to new environments
An evolutionary study involving guppy fish populations provides insights into how organisms adapt to environmental change, reports a paper published in Nature this week.
Changes in the environment drive organisms to alter their characteristics, and this can occur through evolutionary changes across generations (genetic adaptation), as well as through plastic changes in gene expression within a generation (phenotypic plasticity). Although it is known that phenotypic plasticity may influence evolutionary change by altering the distribution of phenotypes upon which natural selection acts, it is not currently clear whether it facilitates or hinders genetic adaptation.
Cameron Ghalambor and colleagues transplant wild Trinidadian guppy fish (Poecilia reticulata) from a stream with predatory pike fish into two predator-free streams, and compare brain gene expression patterns between the original and the transplanted populations after three to four generations, as well as with a native predator-free population. They find that when the phenotype varies in the same way as is favoured by natural selection (adaptive plasticity), the genes that gave rise to the phenotype tend not to evolve in response to selection. Conversely, when the phenotype varies in the opposite way (non-adaptive plasticity), those genes evolve rapidly.
“A question that needs to be addressed in future studies is whether results from gene expression analyses can be extended and generalized to macroscopic traits that have more direct ecological relevance,” says Juha Merilä in an accompanying News & Views article.
Cameron Ghalambor (Colorado State University, Fort Collins, CO, USA)
Tel: +1 970 402 6505; E-mail: email@example.com
The paper is available for download at http://dx.doi.org/10.1038/nature15256
Andrew Furness, another FIBR Alum, has been awarded an NSF post-doctoral research fellowship in biology, with am emphasis on research that makes use of museum collections. The title of his project is: "The evolution of the placenta in poeciliid fishes: testing adaptive and conflict hypotheses." Congratulations Andrew!
February 2015. Greg Larsen becomes assistant editor for Lab Animal Congratulations to former intern and field manager Greg Larsen on his new job as assistant editor for Lab Animal, a publication of Nature Publishing Group!
January 2015. New position for Abby Sage, a former FIBR Guppy InternAbby Sage, a former intern has a new position as a researcher at Kruger National Park in South Africa. She is working on a disease ecology project on African Buffalo. Congrats on the new job!
December 2014. Martin Turcotte is awarded a competitive post-doctoral fellowshipCongratulations to Martin Turcotte for being awarded the competitive Adaptation to Changing Environments (ACE) post-doctoral fellowship at ETH Zürich!
October 2014. Andrew Furness appointed post-doc at UC IrvineFIBR Guppy alumni Andrew Furness has joined John Avise's lab at UC Irvine as a post-doctoral researcher.
May 2014. A blog on the day-to-day life of a FIBR Guppy Intern, stories from the Guppy HouseKaren Backe, former field intern, has made a blog about what it is like to work on the FIBR Guppy Team. For insights and photos on the day-to-day life of a FIBR Guppy intern in Trinidad, check out her blog here. The Trinidad posts are all under the May 2014 section.
May 2014. News on FIBR Guppy InternsJohn Kronenberger is finishing his first year as a PhD student at Colorado State University.
Gregor Sigmund and Cinnamon Mittan will matriculate as graduate students at Cornell in September 2014.
Congratulations on these achievements!
April 2014. Sonya Auer wins post-doctoral fellowshipBelated congratulations to Sonya Auer for winning a post-doctoral fellowship to work with Neil Metcalfe at the University of Glasgow!
April 2014. Matt Walsh becomes assistant professorBelated congratulations to Matthew Walsh for becoming an assistant professor at the University of Texas, Arlington!
April 2014. Swanne Gordon is awarded post-doctoral research grantCongratulations to Swanne Gordon for receiving a highly competitive post-doctoral researcher grant to continue her work at the University of Jyvaskyla!
March 2014. Two new post-doc positions for FIBR alumniRon Bassar has accepted a post-doc position at Oxford University with Tim Coulson. Also, Martin Turcotte will work as a post-doc with Jonathan Levine at ETH Zürich. Both will start their positions in Summer 2014. Congratulations Ron and Martin!
March 2014. Jennifer Hoey headed to Rutgers UniversityJennifer Hoey, a former intern (2011-2012), has accepted a PhD position at Rutgers University in the department of Ecology and Evolotionary Biology. Starting fall 2014, she will work with Malin Pinksy. She has also been awarded an NSF Graduate Research Fellowship as well as a GAANN fellowship. Congratulations Jennifer!
November 2013. More media attraction for the FIBR teamThis experiment changed our understanding of parasite resistance
June 2013. Our latest article attracts the mediaIn a recent article, Andrés López-Sepulcre and colleagues analyze our focal stream data to show that a substantial proportion of males reproduce well after dead, and that this is important for population growth and selection. The findings, published in the Proceedings of the Royal Society of London B, have featured in Science NOW, Science NEWS, Live Science, Yahoo News, NBC News webpage, the Smithsonian blog and a variety of other science news pages around the world.
April 2013. Meredith Palmer wins NSF GRFP award.FIBR alumnus Meredith Palmer has won an NSF predoctoral award to support her PhD at the University of Minnesota-Twin Cities. She will be working with Craig Packer on predator-prey interactions in the Serengeti. Congrats, Meredith!
March 2012. Ron Bassar wins young researcher awardRon Bassar, who graduated with us, has won the 2012 Hynes Award for New Investigators from the Society for Freshwater Science. Congratulations Ron!!
Winter 2011-2012. The FIBR post-doc diaspora.We are proud to announce that many of our PhD students have graduated throughout the last year and gotten wonderful post-docs around the world. Sonya Auer at University of Montana (USA), Ron Bassar at University of Massachussets (USA), Swanne Gordon at University of Jyväskylä (Finland), Julian Torres-Dowdall at University of Konstanz (Germany), Martin Turcotte at University of Toronto (Canada) and Eugenia Zandona at Universidade Estatal de Rio de Janeiro (Brazil).
February, 2012 - Swanne Gordon accepts post-doctoral position in FinlandSwanne, who worked on the evolution of guppy coloration in our focal fish for her PhD, is moving to the University of Jyväskylä in Finland. She will be researching the role of sexual selection on the evolution of color polymorphism in the wood tiger moth Parasemia plantaginis.
December, 2011 - New video posted!You can find a recent report on the progress in this project in the Video Folder (scroll down to Presentations section) in the form of a seminar given by David Reznick at the Museum of Vertebrate Zoology, UC Berkeley on October 19, 2011.
Nov 26, 2011 - Swanne Gordon's article selected by Faculty of 1000Swanne Gordon's article in Evolution, on the rapid evolution of color sex linkage in guppies was recommended as a 'Must Read' by Deborah Charlesworth on Faculty of 1000. You can read the comment at http://f1000.com/13376970
August 15, 2011 - Martin Turcotte publishes a paper in Ecology LettersMartin Turcotte just published a paper in Ecology Letters entitled The Impact of Rapid Evolution on Population Dynamics in the Wild: Experimental Test of Eco-Evolutionary Dynamics. You can read a press release about his work at
Martin received his PhD at UC Riverside in March, 2011 and is now a post-doctoral researcher at the University of Toronto, where he is working with Marc Johnson.
August, 2011 - Rana El-Sabaawi gets tenure track appointmentRana El-Sabaawi, former post-doc with Alex Flecker at Cornell University, has accepted a tenure track assistant professorship at the University of Victoria, to begin in July 2012.
July, 2011 - Andrés López-Sepulcre gets tenure at CNRS (France)Andrés López-Sepulcre, a postdoctoral researcher for 4 years in the project (at UCR and ENS,Paris), earned a tenured position as CNRS junior researcher in France.
July, 2011 - Keeley MacNeill gets Fulbright Fellowship!Technician Keeley MacNeil has been awarded a Fulbright Fellowship and will work with Dr. Dag Hessen at the University of Oslo. She will study the effects of physical variables on the functional traits of bacteria and phytoplankton in Norwegian and Swedish lakes. Congratulations Keeley!
June, 2011 - Eugenia Zandonà completes PhDEugenia Zandonà completed her PhD and received the 'Best Dissertation Award in Physical and Life Sciences' from Drexel University for her thesis, which was affiliated with the FIBR project. She characterized how guppies from high versus low predation environments differed in diet, gut structure and stoichiometry. Her current position is: CNPq Post-Doctoral Fellow at the State University of Rio de Janeiro (UERJ) with Dr. Timothy Moulton. She is studying fish and shrimp stoichiometry and excretion to investigate their role in nutrient cycling in coastal streams of the Atlantic Forest. CNPq is the Centro Nacional de Pesquisa, which is the Brazilian version of NSF.