Experimental study of species invasion: early population dynamics and role of disturbance in invasion
David Reznick, Sebastiano de Bona, Andres Lopez-Sepulcre, Paul Bentzen, Ron Bassar and Joe Travis
See our new lab publication, just released: Eco-Evolutionary Feedbacks Predict the Time Course of Rapid Life-History Evolution. American Naturalist 194: 671-692. DOI: 10.1086/705380.
This work is part of our ongoing experimental study of the interactions between ecology and evolution in natural environments. We extended the range of guppies over barrier waterfalls that had excluded them from headwaters and have followed their population growth with monthly mark-recapture plus monitored their impacts on the only other resident fish species and the ecosystem. We assayed life history evolution (male age and size at maturity) with common garden experiments executed every year for the first four years after the introduction. We observed a lag in when male traits evolved that corresponds to the onset of density regulation.
Joshua Goldberg successfully defended his PhD yesterday - Thursday, October 10. His thesis title is: "Population, spatial and temporal structure in the development of a stream community". It was a series of studies of the interaction between guppies and the killifish, Rivulus hartii as guppies invade a headwater stream where killifish were the only prior resident. The three chapters were: 1) artificial stream experiments that detailed the nature of their interaction, 2) mark-recapture studies of killifish where guppies were introduced, in comparison with an upstream control from which guppies had been excluded by a barrrier waterfall, and 3) how these interactions "matured" over time in longer term introduction experiments (30+ years) and natural communities with both species present.
It was a great presentation. We are all very proud of him and happy with the outcome.
Joshua will soon return to Bhutan to study tigers and leopards!
A recent publication about the consequences of recognizing evolution as a contemporary process:
Reznick, Losos and Travis. 2019. From low to high gear: there has been a paradigm shift in our understanding of evolution. Ecology Letters 22: 233-244
Matt Walsh (PhD 2009) was just awarded the "Presidential Early Career Award for Scientists and Engineers" (PECASE). He was nominated by the National Science Foundation on the basis of his CAREER grant and subsequent research success. He may get to shake Donald Trump's hand! Congratulations Matt!
Book review of James Costa's biography of Darwin's latter life at Downhouse. Costa does a terrific job describing Darwin's approach to empirical science.
My perspective, co-authored with Joseph Travis, came out in Science today. We comment on Patrik Nosil et al. (2018) who assess the (un)predictability of evolution in Timema stick insects. Their work raises questions as to why evolution is predictable in some systems (e.g., microbes and viruses), but not others.