Monday, August 31, 2009
This week there will not be any lab-meeting on Wednesday (2 September), as I am catching up on various administrative work and waiting manuscripts after the ESEB-meeting in Italy. I aim for a lab-meeting next week, though, on Wednesday September 9. Suggestions for papers are welcome, and if you do not have any I suggest that we discuss a few papers about intralocus sexual conflict, which was a popular topic at the ESEB-meeting last week.
I would also like to say goodbye to our great co-workers Master's student Lisa Orr and postdoc Shawn Kuchta, who are now leaving us, after one and two years, respectively. I hope best for their future careers. We surely all hope to see you again in Lund at some point in the future. As our lab has now temporarily shrunk in size (hopefully temporarily!) it becomes even more important that we all go to the lab-meetings to get good discussions and have the necessary "critical mass" in terms of number of participants when we discuss papers.
Following some advice from Shawn and how many labs function in the US, I have therefore now decided that our lab-meetings will from now on be compulsory for the three PhD-students whom I am still the main advisor of: Anna, Tina and Fabrice. If one of you can't make it for a Wednesday meeting, you should contact me well in advance so that I know this and can cancel in time if we are not enough participants for meetings. Legitimate reasons for not participating in a lab-meeting include sick leave, maternity leave, conferences, field work or lab work outside Lund, or when I am away travelling. Lab work in Lund or manuscript writing are not legitimate reasons for absence on Wednesday meetings.
This new rule, which ultimately will be to the benefit to all of us, will start operating from September 9. The next PhD-student to defend his thesis, Fabrice, has to follow this rule at least until his dissertation on November 20 (and hopefully voluntarily after that as well). I encourage you all to also try to bring in those PhD-students for whom I am not main advisor for to get an even bigger discussion group, e. g. Josefin and Sanna. Master's students are also always very welcome. We might soon have a new Canadian Master's student from Canada (Andrew McAdam's lab) coming in next year, by the way, and two new postdocs (Sophia Engel and Machteld Verzijden) are also in the pipeline. The more participants and lively discussions in the lab-meetings the better, for you and your PhD-education. I hope that we can soon discuss some of Fabrice's thesis-chapters and a new manuscript by Anna on Podarcis-lizards in September or early October.
Wednesday, August 26, 2009
The second full conference day in Turin has been spent in the symposium that I organized (together with Alexis Chaine) entitled The phenotype-fitness map revisited: agents of selection and the importance of ecology in evolutionary studies. This symposium was, I would say, a HUGE success, and the room was crowded from the very beginning. It is clear to me that evolutionary biologists are increasingly realizing that they should not take ecology as "given" or treat it as a "black box" and only focus on DNA-sequence variation, which has been dominating these evolutionary conferences a lot the past decade.
Luckily, things are now changing and there is an increasing interest in the actual ecological causes of selection and their effects of evolutionary diversification. These ecological factors include inter- and intraspecific competition, predation, parasitism, social environments, to name only a few. Todays speakers included Craig Benkman, who gave an interesting overview of the crossbill radiation in North American Europe (see picture above!) and its ecological causes: the size and hardness of the cones of coniferous trees. Benkman showed that selection on cones by crossbills changes if there are also squirrels present in the area, a nice example of how interspecific competition can have a dramatic effect on evolutionary trajectories.
The other invited speaker was Stevan J. Arnold, a legendary evolutionary biologist and quantitative geneticist, who developed the statistical framework of estimating selection gradients in natural popualtions (together with Russel Lande). It was therefore very nice to see both Steve Arnold and Russ Lande sitting on the front row of this symposium, enjoying the fact that their landmark paper from 1983 (published in Evolution) still inspires workers today. Few papers in evolutionary biology has been cited as much as this landmark one.
Steve Arnold gave a talk about how the adaptive landscape model of microevolution can be extended to the macroevolutionary scale to understand phenomena like adaptive radiations. He presented some new models and a newly developed software (MIPoD: Microevolutionary Inference from Patterns of Divergence) that can estimate parameters like the strength of long-term stabilizing selection and its relationship to genetic drift and other evolutionary forces, using phylogenetic data, estimates of effective population sizes and phenotypic and genetic information from different evolving populations. He illustrated this new approach using his own collected empirical data on the number of vertebrae in gartern snake populations from different parts of North America.
Now, I will go and have a beer with my close college Tom van Doorn to prepare for tomorrow, which will include a trip to Mont Blanc in the afternoon. Hopefully, we will see some nice Alpine birds!
Tuesday, August 25, 2009
I am currently in Turin (Italy), participating in the European Evolutionary Biology Meeting, organized by European Society for the Study of Evolutionary Biology (ESEB). I travelled down to Italy with a dozen of my colleagues from the Ecology Department by train, a nice trip that took about 24 hours. We passed through the Alps and enjoyed the sight of the extensive grape fields in northern Italy before we reached our final destination. A nice experience that was also both climate-smart and environmentally friendly, compared to the usual flight trip.
What has happened this first day? Well, Hanna Kokko from University of Helsinkki gave an excellent keynote plenary about the need to incorporate ecology, particularly population dynamics, in evolutionary studies (and not only genetic factors). Being an ecologist myself, I could not agree more, and actually, tomorrow (Wednesday August 26) I am hosting a full-day symposium about the need to incorporate ecology, particularly information about selective agents (predators, parasites, inter- and intraspecific competitors etc.) and selective causes in studies of natural and sexual selection in the wild. Our two invited speakers tomorrow are Stevan J. Arnold and Craig Benkman, two well-known field evolutionary ecologists who have done excellent work in this spirit in natural populations of birds (crossbills) and amphibians (salamanders).
Back to Hanna Kokko. One of her most interesting points today was a critical re-evaluation of Bateman's principle, the idéa that differences in gamete size of males and females (i. e. eggs and sperm) is the main explanation for differences in reproductive strategies and sex-differences in parental care. This idéa has long been popular in evolutionary psychology and classical behavioural ecology, and it was taught to me as more or less a "truth" when I took courses in behavioural ecology and animal ecology in Lund in the late 80'ties and early 90'ties.
As many other popular idéas in behavioural ecology (a field with an unfortunate tendency of forming scientific "bandwagons") it was an oversimplification and Kokko convincingly argued that there are many other ecological factors than differences in gamete size that are likely to override these initial sex-differences and which are likely to be as important (or even more important) to explain sex differences in partental care. Among these factors are the operational sex ratio (OSR), which should (all else being equal) favor more male parental care when there are few females available and less mating opportunities, for a simple reason: males might then benefit more from providing parental care than try to hunt the few females that are available in the mating pool.
I suspect that Bateman's Principle will be start to become more critically questioned among evolutionary biologists in the future, although the hardcore dogmatic ones that remain (some of them in Lund) might not give up their pet idéa that easily and might be hard to convince. Paradigm shifts in the sense of science philosopher Thomas Kuhn sometimes need that some reactionary key figures retire, before new idéas can establish themselves, and this is also true for behavioural ecology and evolutionary biology.
Talking about pet idéas, another such (in Lund and at many other places) has been the so-called "good genes"-model of sexual selection. This popular hypothesis, which has actually quite limited empirical support in spite of its extreme popularity, was almost a dogma in the nineties in Lund and Uppsala and many other animal ecology departments. The idéa is that male secondary sexual ornaments (signals), like bright feathers and colour patterns, primarily evolve through the force of indirect selection for genetic fitness benefits of offspring.
Many workers have now pointed out, among them evolutionary geneticist William Rice, that the indirect fitness benefits are quite small and likely to be "swamped" by direct fitness costs (e. g. costs of mating, as shown in fruitflies) or direct fitness benefits (e. g. benefits of male parental care, which is probably present in most birds with parental care). Thus, even if indirect fitness exist, they are unlikely to be important in explaining the evolution of secondary sexual characters, which is of course frustrating for those bird behavioural ecologists who have invested a large part of their careers and prestige in to this particular scientific bandwagon which is no longer that fashionable anymore and actually contradicted by much new data and new theoretical models.
Recently, it has also been demonstrated in fruitflies, reed deer and some other animals that fitness benefits of alleles are sex-specific and that there exists intralocus sexual conflict in the genome: genes which have a positive fitness benefits on sons often have a detrimental fitness effect on daughters, which should further diminish the indirect fitness benefits of females mating to attractive males. This topic and other obstacles to the "good genes" were adressed in a symposium entitled Are “good genes” theories of sexual selection finally sinking into the sunset?. Well, one could hope so, or at least that people in behavioural ecology start to think more critically about this issue and that they do not take these "good genes" (important or not) as much as for granted as they have done in the past.
Monday, August 17, 2009
This week, I have the pleasure to announce two lab-meetings, one on Wednesday (10.00-12.00) and the other on Thursday (10.00-12.00). Both will take place in "Darwin", as usual. I hope as many as possible will come. There will be no article to read, but interesting research presentations.
On Wednesday, Shawn Kuchta and I will present our talks that we will give at the coming European Evolutionary Biology Meeting (ESEB), that will take place in Turin (Italy) next week. Shawn will talk about selective predation on wing morphology and geometric morphometrics in calopterygid damselflies, i. e. the work he has done during his two year postdoctoral visit in Lund. Shawn will present his talk in Turin in a symposium organized by me and Alexis Chaine about the role of ecology and selective agents in evolutionary biology studies. You can find the programme here for that symposium.
As for myself, I will talk about the genetics of life-history trade-off, which is the topic of a symposium at the ESEB-meeting where I have the pleasure of being an invited speaker (the other one being Derek Roff). Our presentations will be very informal, and there will be room for suggestions of how Shawn and I can improve our presentations. We are looking forward to your feedback!
On Thursday, my colleague Almut Kelber from the department of Cell- and Organismal Biology (COB) and her postdoc Miriam will visit us to talk a little bit about our collaboration that has been ongoing the last summer about sensory physiology, colour vision and colour physiology in our model damselfly species Ischnura elegans (see picture above!). I will also give a short presentation about damselflies as model organisms in ecology and evolution. Mirjam will bring fika, and I encourage all of you who might be interested in this to join in!
Saturday, August 15, 2009
Some of you might be interested in this recent study published in PLoS ONE about rapid evolutionary changes in morphology in rodents. I served as an academic editor on this interesting paper, that has gained quite a lot of media attention, e. g. in Science News and in Los Angeles Times. Since I was academic editor for this article, I was interviewed about it and I briefly comment upon it in the Science News article.
Although media attention and coverage is not, and should certainly not be, the only criterion for scientific "quality" (whatever that is!), it is further testimony of the advantage to publish in "Open Acess"-journals in general, and PLoS ONE in particular. This study is also interesting because it shows the value of museum collections as a source for ecological and evolutionary research, a point that Shawn Kuchta has repeatedly emphasized in our lab-meetings (and which I completely agree with, of course).
Oliver Pergams and his colleague Joshua Lawler used a large data set consisting of thousands of museum specimens, collected from various places of the world and during a long time period (more than a century) to track changes in morphology of the skull of rodents. They analyzed statistically which traits that changed, and how much. They further linked these morphological changes to two ecological factors: increasing urbanisation (i. e. increasing local human population densities) and climatic factors.
They found that both urbanisation and climatic factors were statistically significantly related to the morphological changes they observed. Although not all these morphological changes are understood from a functional viewpoint, and the genetic basis of the changes are not known, the study is strongly suggestive. Rapid evolution in rodents might thus be a result of both humans directly, and possibly indirectly through anthroprogenic climate change.
Friday, August 14, 2009
For those of you who have not followed Swedish TV- or radio the last days, I would like to point to a couple of programs where our research on Calopteryx splendens and Calopteryx virgo has been covered. First, the regional TV-news channel "Sydnytt" has a 2-minute interview with me at Klingavälsåns Naturreservat, where I am interviewed in the field, and where I discuss the potential consequences of future climate change. You can watch this programme here.
Second, the popular science radio programme "Vetandets Värld" has a 20-minute programme, where both I and Anna Runemark are interviewed, about our learning experiments on mate recognition. Also, our physics-colleagues are interviewed about the laser-studies that were performed at Klingavälsån och what they can inform us about the behaviour of damselflies. You can listen to this programme here.
Saturday, August 8, 2009
This coming Wednesday (12 August 2009), we will have our first lab-meeting for this semester. I suggest that we discuss this TREE-article by Rundell and Price about ecological and non-ecological speciation (and adaptive and non-adaptive speciation).
This article, as well as the second author's recent book Speciation in birds has been somewhat of an eye-opener, at least to me. Trevor Price's recent speciation-book might seem somewhat taxonomically narrow, since it only deals with birds. However, the book is a superb reading, also for those who work with other organisms (including insects!). Trevor makes a strong case for learning playing an important but under-appreciated role in the speciation process of birds, and backs up his claims by massive empirical data in a thorough review.
This was one of the major insights I got from reading his book during the summer, the other one was that I realized that the evidence for ecological speciation (and sympatric speciation, which is a sub-set of ecological speciation) is not that strong as one might think after reading Dolph Schluters equally excellent book The Ecology of Adaptive Radiation. In reality, many workers have in the recent past demonstrated ecological differences between closely related taxa, which is not the same thing as evidence for ecology playing a major role during the speciation process that formed the same taxa. Thus, the ecology of species differences is not the same thing as ecological speciation, just as the genetics of species differences is not the same thing as the genetics of speciation!
These subtle, but important issues, are dealt with in detail in Trevor's critical overview of the state-of-the-art of the speciation field. In practice, we might never be able to confidently state that a group of closely related species speciated because of ecological differences caused the reproductive isolation, particularly when the taxa are old and when it becomes difficult or impossible to infer ancestral character states (ecologies). Trevor makes a strong case in the article, and in his book, that many species of birds most probably did not speciate because of ecological factors, but rather because of geographical isolation during a prolonged period in allopatry. Ecological differences between species often emerged later, upon secondary contact in sympatry. He might be correct, although you will have to read the book and the article for yourself to decide where you stand on these issues.
Full reference and abstract to the article (in case the link above does not work): Time as usual: 10.00 on Wednesday (12 August) in "Darwin".
Saturday, August 1, 2009
For those of you who did not already know this, our beloved former co-worker Tom Gosden received a three-year postdoctoral fellowship from the "Marie Curie"-programme. I wrote a blogpost also about this at the CAnMove-blogg, which you can read here. This is good news, not only for Tom, but also for me and our entire research laboratory, since Tom will return to Lund in the third year of his postdoc, with the aim to build up a Drosophila-laboratory here, in collaboration with me.
Tom's brave decision to move from a field-based evolutionary ecology system (Ischnura elegans, his thesis-work) to a more classical lab-based system of Drosophila will most likely pay off in the future. Hopefully, in the future we can combine concepts and methods from the Drosophila-world with the Ischnura-system, particularly if we one day are able to characterize the colour morph-locus of I. elegans at the DNA-sequence level.
Although we are not there yet, Maren Wellenreuther will next year start on her Marie Curie postdoc project that will bring us closer to that long-term goal, with the primary (and more realistic) aim to first produce a linkage map and find a molecular marker of the morph-locus. Luckily, we have molecular ecology expert help from Bengt Hansson in this hunt for the magic morph gene.