Lab-meeting on multiple adaptive peaks and predator-mediated natural selection

Posted by Erik Svensson

On Tuesday (April 30, 10.30) I was thinking that we should discuss a short paper that was recently published in Science, showing an empirical example and application of the Adaptive Landscape concept. I choose this paper to demonstrate that the idéa of the adaptive landscape is not just a theoretical construct, but could actually stimulate empirical and experimental studies. This was also the main rationale for the publication of our book on the topic last year, which is cited in the current paper. You will find the Abstract below, and the paper can be reached here. 

As another example of how "landscape thinking" and fitness surfaces can guide empirical work, I will also send around a manucript draft about predator-mediated natural selection in Calopteryx-demoiselles, that stems from the field work former postdoc Shawn Kuchta did in our lab between 2007 and 2009. We would both love to get some input on this manuscript, short or long, either during the lab-meeting or before or after (if you cannot attend). I will send you an e-mail with this paper attached well before the lab-meeting, but if you do not receive it and wish to have a copy, please do not hesitate to send me an e-mail (erik.svensson@biol.lu.se).

Any fika-volunteer?

Science 11 January 2013: 
Vol. 339 no. 6116 pp. 208-211 
DOI: 10.1126/science.1227710

• REPORT

Multiple Fitness Peaks on the Adaptive Landscape Drive Adaptive Radiation in the Wild

1. Christopher H. Martin*, 
2. Peter C. Wainwright

• ABSTRACT

The relationship between phenotype and fitness can be visualized as a rugged landscape. Multiple fitness peaks on this landscape are predicted to drive early bursts of niche diversification during adaptive radiation. We measured the adaptive landscape in a nascent adaptive radiation ofCyprinodon pupfishes endemic to San Salvador Island, Bahamas, and found multiple coexisting high-fitness regions driven by increased competition at high densities, supporting the early burst model. Hybrids resembling the generalist phenotype were isolated on a local fitness peak separated by a valley from a higher-fitness region corresponding to trophic specialization. This complex landscape could explain both the rarity of specialists across many similar environments due to stabilizing selection on generalists and the rapid morphological diversification rate of specialists due to their higher fitness.

Praise for our book "The Adaptive Landscape in Evolutionary Biology"

As you hopefully remember, last year Ryan Calsbeek at Dartmouth College and I published an edited volume entitled "The Adaptive Landscape in Evolutionary Biology" (Oxford University Press 2012). Although we have generally gotten positive feedback and responses when talking research colleagues at meetings, relatively few reviews have yet appeared, probably because it is a relatively recent publication. Here is one very flattering review, however, published on the blog "Nothing in biology makes sense".

I thank the blog author for his kind words, and have to cite some of the nice formulations on a very long and thorough review:

"Unlike a recent book addressing aspects of the modern synthesis, Evolution: The Extendend Synthesis (Pigliucci and Müller, 2010) which called for a revolution, Svensson and Calsbeek have assembled authors that explore the innovations and contributions that build upon the fundamental ideas of population genetics and seek to grow the field. Early in this book, Pigliucci asks about the utility of the Adaptive Landscape metaphors, even titling his chapter with the question, “what are they good for?” I think the rest of the book provides a more than sufficient answer to his question."

and:

"Over the course of this semester, my colleagues and I read and discussed each of the chapters. Our group consisted of a diversity of backgrounds spanning evolution, ecology, and behavior. We included a range of experience from first and second year graduate students to postdocs as well as junior and senior faculty. While we read the book in the sequential order it was published in, each part could certainly be pulled out and read as a separately. Some of the chapters make cross references to each other but not enough that reading them independently would be impossible. While some chapters certainly provided more challenges to some, this forced our discussion to flesh out explanations that the text just didn’t have time to go into. I think that the first two parts might make particularly good set of readings to supplement an upper level Evolution or Population Genetics course."

and:

"My recommendationThis is a book ideally suited for a graduate level seminar in any Biology department. While it may be good to read a few chapters on your own, the book benefits from an active discussion of the content. We took 14 weeks to go through the entire book, reading one chapter most weeks occasionally two (or three). This pace allowed everyone to casually complete the readings. Going slowly through the book also allowed us to digest the material and make connections among the chapters without getting too overwhelmed with new information each week. You can follow this link to see the schedule we followed. If you are not convinced about the utility of this book yet, below I highlight some of the excellent contributions contained within the different parts."

and finally:

"CONCLUSION: I would strongly encourage students of population genetics to pick up this excellent volume and spend some contemplative weeks reading through the chapters. Better yet, grab a group of your department colleagues and argue about the 80 years of interpretation of the Adaptive Landscape. I personally cannot wait to see where this excellent metaphor leads us."

Lab-meeting on the history of the Adaptive Landscape

For next week's lab-meeting, we'll become more philosophical and historical, and discuss a book chapter about the history of the Adaptive Landscape metaphor in evolutionary biology. This chapter will be one of approximately 20 chapters in a forthcoming volume at Oxford University Press that I am currently editing together with my colleague Ryan Calsbeek (Dartmouth College, New Hampshire, USA).

This volume is intended to become published in 2012, which marks the 80-year celebration of population geneticist Sewall Wright's famous paper in 1932 where the concept of the Adaptive Landscape was first explicitly presented. Both Ryan and I are looking forward to input on this chapter, and in case you have not received a copy prior to our lab-meeting and wish to participate, send me an e-mail (erik.svensson@zooekol.lu.se). Time and location for lab-meeting as usual: "Darwin" at 13.30-15.00 on March 2, 2011. Fika volunteers are most welcome!