Tuesday, December 28, 2010

Happy New Year!

I hereby wish all my co-workers (students, PhD-students, postdocs and colleagues) a Happy New Year 2011! I certainly hope that the new year will be as succesful as the previous was, for many of us. Apart from several good publications in excellent journals (BMC Evolutionary Biology, Evolution, J. Evol. Biol., TREE to mention only a few) I would also like to highlight some other great highlights (to me personally):

1. Kristina Karlsson succesfully defended her PhD in November and have already published most of her thesis-papers. Well done!

2. Fabrice Eroukhmanoff got a postdoctoral 2-year grant from The Swedish Research Council (VR) to go to Norway (Oslo University) and work with Glenn-Pether Saethre and Thomas F. Hansen.

3. Machteld Verzijden found out, just before Christmas, that she will stay in our lab for 2-3 more years, due a postdoctoral scholarship from the Wenner-Gren Foundations.

4. Former postdoc Shawn Kuchta got a faculty position at Ohio University (Athens, USA), and started up his new lab from the beginning of September 2010. Sophia Engel visited him during November, and I will myself go there for a visit in April 2011.

Needless to say: I am proud to work with such a group of excellent and dedicated scientists as you guys! Although academic life is stressful and we compete (like all other groups) for grants and to get our papers published in good journals, I think we are doing remarkably well, as a lab and as a group. I think this is because we regularly meet and discuss science - in a friendly and cooperative atmosphere. This is the key to sucess - much more than large research grants. I hope we can continue along this succesful path for many years to come.

As for myself, I will now leave for South Africa (well, tomorrow!), and will be back in the last week of January. Until then; enjoy this picture of a Greater Collared Sunbird, photographed in the Eastern Cape Province in South Africa in April this year. My overly ambitious daughter My (who is soon a professional blogger and expert in HTML-programming, by the way), has started up a new photo blog, where she wants us both to upload our photos during the trip to South Africa. You can find it here.

I am not sure I will allocate that much time as my daughter expects me to, as I want to stay away from the internet for a while, when enjoying field work, good wine, birds and wildlife. But keep following this other blog, perhaps I will change my mind :).

Sunday, December 19, 2010

How we are evolving and more on the "missing heritability" problem

Although I suggested  we should skip articles for next lab-meeting (Wednesday 22 December), I changed my mind after finding a couple of interesting papers in the popular science magazine Scientific American. Both deal with human evolution and human genetics, and should be an easy read, and are of much principal interest, also to us.

The first one raises the question "How we are evolving" and it discusses the recent recent data obtained from "Next-generation sequencing" that have elucidated the evolutionary history of coding genes in Homo sapiens. It turns out that so-called "selective sweeps" are quite unusual in our genome, i. e. alleles that have quickly increased in frequency in response to local selection pressures and in local environments. Thus, the case of the recent demonstrated selective sweep in the genes affecting haemoglobin production when humans invaded the Tibetan Plateau that we discussed earlier this year, are atypical, and do not seem to be the norm (according to the article in Scientific American).

Instead, it appears that the global distribution of human coding genes more reflects recent migration histories: genes that increased in frequency at a certain place were then carried along to new places as human colonized the Earth. This implies that selective sweeps are rare, and they mainly happen when there is strong and sustained selection that is consistent over relatively long time at a given place. This implies that selection might in general be relative weak, in humans at least. Perhaps humans are able to adapt (culturally) and counteract selection pressures by cultural adaptations, such as clothing, food habits etc., which weakens natural selection in many environments?

The other article in Scientific American deals with the so-called "missing heritability"-problem, i. e. the uncomfortable facts that there are very few genes explaining a substantial amount of variation in diseases. Thus, most large-effect genes are quite rare in the populations, whereas those genes that are common explain only a tiny fraction (in the order of a few percent) of the disease-related variation. This has caused despair among molecular biologists and biomedical researchers, since the huge amount of sequencing data has not solved many of Homo sapiens biomedical problems (contrary to promises in the most enthusiastic heydays of genome sequencing). In spite of thousands of variable SNP:s ("single-nucleotide polymorphisms"), only a few percent of the total amount of variation in human phenotypic traits are explained by these molecular markers. This can either be interpreted as a great disappointment (in relation to promises), a complete failure for molecular biology or a great triumph of quantitative genetics, but as usual, the questions that are raised by these findings might be more interesting than the exact answers. The solution? Well, certainly not to sequence more or try to obtain more SNP:s, but rather to think harder (surprisingly, an underutilized strategy in much of today's science!).

The two articles can be found here and here, and I think you will enjoy both, as they are relatively easy read. Let's have a brief and informal discussion about these papers on Wednesday, after we've had some glögg!

Friday, December 17, 2010

Soon Christmas and last lab-meeting for this year on December 22 2010

Wednesday 22 will be the last lab-meeting for this year before Christmas, and before I leave for South Africa. I was thinking we should skip a paper this time, and just discuss some general issues and any remaining practicalities before the winter break. I will bring "glögg" (both with and without alcohol!), if somebody else could volunteer to bring "lussekatter" and/or pepparkakor.

Hope to see you in "Darwin" then on December 22. Same time as usual: 10.15.

Interesting blog about "Eco-evolutionary dynamics" by Andrew Hendry's lab

Those of you have met Andrew Hendry before, either in Vienna during the "Speciation"-meeting last week, or last year when he was the external opponent on the PhD-thesis by Fabrice Eroukhmanoff, might enjoy this blog from his research laboratory. His lab seem to have a similar attitude as ours when it comes to public outreach and using social media, which is nice. A general theme of their blog is "Eco-evolutionary dynamics", which fits well with the kind of research Hendry et al. have been pursuing in recent years, using sticklebacks, guppies and Galápagos finches as study organisms. Enjoy!

Tuesday, December 14, 2010

Greetings from "Speciation-meeting" in Vienna!

Together with several other colleagues from Lund, Sweden and other countries, our lab was well-represented at the first European Speciation Conference, organized by the Institute for Advanced System Analysis (IIASA) in Vienna (Austria). This three-day conference has gathered a number of researchers working on the problems of speciation, both theoretically and empirically. A list of talks from the conference can be found here.  

The first evening of the conference, we enjoyed nice Austrian food (LOTS of meat!) and good wine, and of course the company of many of our colleagues. On the picture above you can see how happy we are after tasting some great wine. From left to right you see Anna Runemark (Lund University), Fredrik Haas (currently at Oslo University), Erik Svensson (Lund University), Andrew Hendry (McGill University, Canada), Anna Qvarnström (Uppsala University) and Jörgen Ripa (Lund University).Although this time there was a Scandinavian bias at the table, we have also of course interacted and entertained ourselves with some other great colleagues, such as Maria Servedio as well as former McArthur student and legendary ecologist Mike Rosenzweig.

 Personally, I mostly enjoyed the talk by Daniel Bolnick (University of Texas at Austin), about the rarity of sympatric speciation in sticklebacks, which was somewhat heretical in a conference that has been so dominated by the "Adaptive Dynamics"-school, led by Ulf Dieckmann at IIASA, where the importance of sympatric speciation has been vastly exaggerated, in relation to its real importance in natural populations (in my personal opinion). If sympatric speciation was as common as these models of "evolutionary branching" indicate, there would essentially be a new species on every twig of a bush, which there clearly isn't. This very fact in itself suggests (at least to me) that constraints on sympatric speciation are likely to operate and be important, and that the asexual modelling approach in the adaptive dynamics school has underestimated the severity of recombination.

As a primarily empirically oriented evolutionary biologist, I see a major weakness of the Adaptive Dynamics-school in that their models are only weakly connected to empirical work and the parameters they include in their models are not as natural to estimate as the classical and well-established estimates typically  used by field evolutionary biologists that are derived from quantitative genetics (i. e. selection coefficients). In the absence of such transparent models with parameters defined in an empirically meaningful way, the jury is still out whether adaptive and sympatric speciation is really important in nature, or whether it is mainly a phenomena that gains more attention from theoreticians than it deserves from an empirical point of view of practicing naturalists and field biologists.

Our learning paper is covered by German radio

Our recent paper on learned mate preferences in Calopteryx splendens females has now also been covered in German Radio. An excerpt from an interview Joachim Budde made with me in the German Radio channel Deutschland Funk is available here, unfortunately only in German. Enjoy!

Sunday, December 5, 2010

lab meeting December 8

For this week's labmeeting I have chosen a review on the evolution of sexual dimorphism in Lepidoptera, by Cerise Allen, Bas Zwaan and Paul Brakefield (all of whom I know from Leiden, though none of them are there anymore). In this paper they review the evidence for the relative contributions of natural and sexual selection to the evolution of sexual dimorphism.
Though none of us work on Lepidoptera, we do all work on sexual dimorphism in one way or another, so in that sense it's right on topic for us!

You can download this paper here.
The abstract is below some of my own pictures from Lepidoptera from the American continent.

Evolution of Sexual Dimorphism in the Lepidoptera

Among the animals, the Lepidoptera (moths and butterflies) are second only to beetles in number of described species and are known for their striking intra- and interspecific diversity. Within species, sexual dimorphism is a source of variation in life history (e.g., sexual size dimorphism and protandry), morphology (e.g., wing shape and color pattern), and behavior (e.g., chemical and visual signaling). Sexual selection and mating systems have been considered the primary forces driving the evolution of sexual dimorphism in the Lepidoptera, and alternative hypotheses have been neglected. Here, we examine opportunities for sexual selection, natural selection, and the interplay between the two forces in the evolution of sexual differences in the moths and butterflies. Our primary goal is to identify mechanisms that either facilitate or constrain the evolution of sexual dimorphism, rather than to resolve any perceived controversy between hypotheses that may not be mutually exclusive.