Plenary talk by Hanna Kokko on partial migration on Wednesday

Our lab-meeting about the genetics of high-altitude adaptation in humans will start somewhat later than usual on Wednesday, namely at 10.30 on Wednesday September 1, and not the usual time at 10.15. The reason is that there will be an interesting plenary lecture about the evolution of partial migration by Professor Hanna Kokko (University of Helsinkki) that will start at 09.40 in the "Blue Hall".  

Hanna is an excellent speaker, so we might not want to miss this. Her talk will end approximately 10.20, and after that we will start our regular lab-meeting. During the rest of the day and in the afternoon, there will be other interesting talks during the symposium on partial migration, which might be worth attending.

And from 17.00 and onwards, there will be a "CAnMove"-barbecue, organized by postdocs Sophia Engel, Ben Chapman and Miriam Liedvogel. Contact Sophia for more info (sophia.engel@teorekol.lu.se)

Lab-meeting about high-altitude adaptation in humans

It is time for a new lab-meeting on Wednesday (September 1), and this time I was thinking that we should discuss a recent Science-paper where the auhtors present evidence for genetic adaptations to high-altitude living in Tibet. The paper can be downloaded here. Interestingly, there is also another recent study on the same topic in PNAS, which can be downloaded here. I suggest we read both of them in preparation for the lab-meeting on Wednesday.

These papers has received quite a lot of attention both in media and in the bloggosphere. I can recommend population geneticist Jerry Coynes blogpost about one of these papers on his excellent blog "Why Evolution is true". Coyne has also a more critical blogpost where he cautions against solely relying on statistical approaches on gene frequency changes to infer selection. Being an experimental evolutionary biologist and ecologist by heart, I could of course not agree more with Coyne.

Time of lab-meeting as usual: 10.15 in "Darwin", Wednesday September 1, 2010. Any fika-volunteer?

Also, do not forget that CAnMove organises a barbecue on the same day in the afternoon at 17.00 at the Biology Department. Contact Sophia Engel for more info.


References and publication details:

Genetic Evidence for High-Altitude Adaptation in TibetTatum S. Simonson, Yingzhong Yang, Chad D. Huff, Haixia Yun, Ga Qin, David J. Witherspoon, Zhenzhong Bai, Felipe R. Lorenzo, Jinchuan Xing, Lynn B. Jorde, Josef T. Prchal, and RiLi Ge Science 2 July 2010 329: 72-75; published online 13 May 201013 May 2010 [DOI: 10.1126/science.1189406] (in Reports)

Natural selection on EPAS1 (HIF2α) associated with low hemoglobin concentration in Tibetan highlanders PNAS 2010 107 (25) 11459-11464; published ahead of print June 7, 2010, doi:10.1073/pnas.1002443107

On using social media to recruit future talent in ecology and evolutionary biology

We have talked before about the utility of social media like Facebook and blogs to increase public outreach and disseminate your research. This is one main incentive behind this blog, and I am quite convinced it will create a competitive advantage, compared to the strategy of ignoring social media altogether. Today's young generation of students are increasingly using social media to stay in touch with each other, to scan for job opportunities etc., and senior researchers can simply not afford not to use these new means of communications.

Thus, the correct question to ask is not: "Should I really invest the time to learn how to use social media?", but rather: "Can I afford to ignore social media?".

In my own experience, this blog has been extremely succesful in terms of all contacts I have got, including several postdoc requests, journalists who wants to write about our research etc. Now, this general impression of mine seems to be shared by other people in academia than me. In the latest issue of Trends in Ecology & Evolution, there is an opinion piece entitled "Recruiting future talent in ecology and evolutionary biology" by Joshua M. Ward. He writes, among other things, the following:

"The rising popularity of dedicated social networking sites for academics, such as Academia.edu, shows their importance. However, if your goal is to inspire students who are new to ecology and evolution, you must look elsewhere. Why are large numbers of university admissions departments using social media platforms? The answer is simple enough; it's where the students are. Facebook updates students on what their friends are interested in and which groups they are fans of. As young people continue to spend an unprecedented amount of time online, using Facebook pages and Twitter can increase awareness and support of your research group by initiating a viral spread of content and name recognition from user to user."


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"Investing some time and effort now in presenting your research in a stimulating way can pay off considerably. University research groups and publishers are becoming more confident in the value added by having a strong online strategy. The value of having a presence that extends beyond a predictable website into social-networking sites might not seem obvious at first. However, showing potential students that your research group is at the forefront of developments in public engagement will do wonders for name (and brand) recognition. Ultimately, scientists can no longer rely on the mainstream media or their universities’ mere presence online to ensure continued interest in ecology and evolutionary biology. It is up to us to do the inspiring now."

A role for ecology in male mate discrimination of immigrant females in Calopteryx damselflies?

Dear all,

We have recently published another Calopteryx paper, this time in the Biological Journal of the Linnean Society. The paper is investigating male mate preferences and asks the question if males have the ability to distinguish between immigrant and resident females. Below is the abstract and the link to the paper.
 
A role for ecology in male mate discrimination of immigrant females in Calopteryx damselflies?

MAREN WELLENREUTHER, ELODIE VERCKEN and ERIK I. SVENSSON

ABSTRACT: Sexual selection against immigrants is a mechanism that can regulate premating isolation between populations but, so far, few field studies have examined whether males can discriminate between immigrant and resident females. Males of the damselfly Calopteryx splendens show mate preferences and are able to force pre-copulatory tandems. We related male mate responses to the ecological characteristics of female origin, geographic distances between populations, and morphological traits of females to identify factors influencing male mate discrimination. Significant heterogeneity between populations in male mate responses towards females was found. In some populations, males discriminated strongly against immigrant females, whereas the pattern was reversed or non-significant in other populations. Immigrant females were particularly attractive to males when they came from populations with similar predation pressures and densities of conspecifics. By contrast, immigrant females from populations with strongly dissimilar predation pressures and conspecific densities were not attractive to males. Differences in the abiotic environment appeared to affect mating success to a lesser degree. This suggests that male mate discrimination is context-dependent and influenced by ecological differences between populations, a key prediction of ecological speciation theory. The results obtained in the present study suggest that gene-flow is facilitated between ecologically similar populations.


http://onlinelibrary.wiley.com/doi/10.1111/j.1095-8312.2010.01464.x/pdf

Interesting visitor statistics of our blog: where do our readers come from and how many are they?

Although this blog was never intended primarily to have a big outreach, and was mainly aimed to communicate within our own lab, locally in Lund, you might be interested in some visitor statistics that has accumulated over the summer, since a counter was installed earlier this year. Sofar, we have had about 1500 pageloads, which probably is not equal to the number of visitors, since some visitors come back.

However, I think it is a fairly educated guess that we probably have several hundred visitors, many of them active scientists and biologists. That demonstrates quite convincingly, in my opinion, the value of blogs as an efficient tool of scientific communication. Hopefully, this blog also increases the visibility of our research and could even help to attract students and postdocs, once they discover it.

I have included a graph of the number of downloads this year, and as you see, it has peaked during the summer and then gone down, probably because low activity from us all during the field work and our vacations. Now, however, I think we should all strive to put up more blog posts, and try to keep the blog an active and attractive forum. I have kick-started the fall today with three blog posts, and I am looking forward to more contributions from e. g. Maren, Machteld and Fabrice and of course our colleagues in other countries, mainly Tom and Shawn.

I have also included a map of the geographic origin of downloads and visits. As you see, many downloads come from Sweden and Europe (not surprisingly), but we also have some fans in Australia (hello Tom!), the US (hello Shawn and Ryan) and even Brazil (!). Again, this map and the visitor statistics sends and important message: research group blogs, like the one we have, are extremely useful to communicate science, not only locally within the group, but also globally. So please, do not hesitate to put up new blog posts, including advertisements of your own recent lab-publications, as it increases the visibility of our research and (most likely) results in more future citations. Keep on bloggin'!!! Gotta love it!

 

Former lab-member publishes paper on intralocus sexual conflict on wing shape and wing size

As a follow-up to my previous blogpost about intralocus sexual conflict, it is worth pointing to a new and interesting study by a former lab-member and PhD-student: Jessica Abbott (now postdoc in Ted Morrow's lab in Uppsala). Jessica has studied intralocus sexual conflict over wing size and wing shape in Drosophila melanogaster, during her first postdoc in Adam Chippindale's laboratory at Queens University (Canada). The paper will appear in Journal of Evolutionary Biology, and it can be downloaded here (scroll down the list of publications to the bottom), for those who are interested in details. An abstract is posted below.

The fascinating topic of the evolution of wing shape and the selection pressure operating on wings have also been subject of several other studies in our laboratory, mainly related to natural selection and predation on Calopteryx-wings. Like Jessica, we (Shawn Kuchta, I and Sophia Engel) have been using landmark-based geometric morphometric techniques to quantify wing shape and have been used these measures to estimate the strength of natural selection on wings. More will follow, and in addition to sexual selection and intralocus sexual conflict, natural selection is also likely to play a major role in shaping wing size and wing shape in both fruitflies, damselflies and other insects.

Abbott, J. K., Bedhomme, S., & Chippindale, A. K. (2010) Sexual conflict in wing size and shape in Drosophila melanogaster. Journal of Evolutionary Biology, in press.

Intralocus sexual conflict occurs when opposing selection pressures operate on loci expressed in both sexes, constraining the evolution of sexual dimorphism and displacing one or both sexes from their optimum. We eliminated intralocus conflict in Drosophila melanogaster by limiting transmission of all major chromosomes to males, thereby allowing them to win the intersexual tug-of-war. Here we show that this male-limited (ML) evolution treatment led to the evolution (in both sexes) of masculinized wing morphology, body size, growth rate, wing loading, and allometry. In addition to more male-like size and shape, ML evolution resulted in an increase in developmental stability for males. However females expressing ML chromosomes were less developmentally stable, suggesting that being ontogenetically more male-like was disruptive to development. We suggest that sexual selection over size and shape of the imago may therefore explain the persistence of substantial genetic variation in these characters and the ontogenetic processes underlying them.

Lab-meeting on intralocus sexual conflict and transcriptomics

It is time for the fall's first lab-meeting, and what could possibly be a better start than to discuss a paper about how intralocus sexual conflict might (or might not!) leave a transcriptomic signature in the organism? The study I wish to discuss is a relatively new paper in PLoS Biology by Paulo Innocenti and Ted Morrow. The authors combined quantitative-genetic fitness assays in the fruitfly (Drosophila melanogaster) to investigate sex-biased gene expression and its links to intralocus sexual conflict, i. e. the developmental conflict that arises between male and female phenotypes, that arises due to the fact that both sexes share a common gene pool.

We have discussed intralocus sexual conflict and its consequences in previous lab-meetings, and some of our recent lab-publications that are relevant to this topic can be found here (lizards) and here (damselflies). The authors of the current study used microarrays to study sex-specific transcripts, a technique which is now rapidly replaced by "454-sequencing" and other methods in this rapidly moving field of molecular biology.

The time and place for the lab-meeting is as usual: Wednesday August 15 at 10.15 in the "Darwin Room" (2nd floor, Ecology Building). Fika volunteers are encouraged to step forward. Below, I have put an abstract to the paper which can be downloaded here, and you can also find an interesting short comment by Robin Meadows, also published in PLoS Biology.

Abstract 

When selective pressures differ between males and females, the genes experiencing these conflicting evolutionary forces are said to be sexually antagonistic. Although the phenotypic effect of these genes has been documented in both wild and laboratory populations, their identity, number, and location remains unknown. Here, by combining data on sex-specific fitness and genome-wide transcript abundance in a quantitative genetic framework, we identified a group of candidate genes experiencing sexually antagonistic selection in the adult, which correspond to 8% of Drosophila melanogaster genes. As predicted, the X chromosome is enriched for these genes, but surprisingly they represent only a small proportion of the total number of sex-biased transcripts, indicating that the latter is a poor predictor of sexual antagonism. Furthermore, the majority of genes whose expression profiles showed a significant relationship with either male or female adult fitness are also sexually antagonistic. These results provide a first insight into the genetic basis of intralocus sexual conflict and indicate that genetic variation for fitness is dominated and maintained by sexual antagonism, potentially neutralizing any indirect genetic benefits of sexual selection.

Author's summary

Males and females of many species are different: many of these differences are thought to have evolved because the sexes often have needs and strategies that do not coincide. For example, in fruit-flies, females may do best by concentrating their efforts in acquiring resources to be able to lay more eggs, while males would benefit most from increasing their mating and fertilization success. Such differences generate a sexual “conflict of interests”, and since as a general rule each behavioural, morphological or physiological characteristic is regulated by the same set of genes in the two sexes, this conflict takes place ultimately at the genetic level. In our study, we combined data on the reproductive success of different lines of fruit-flies with their gene expression profiles. We show that a large proportion of genes that contribute to male fertilization success are detrimental for female fecundity, and vice-versa. These results indicate that an optimal genotype for both sexes does not exist: many genes maintain different variants because they have opposite effects in males and females, perhaps helping to explain how genetic diversity is maintained in the face of selection.

Citation: Innocenti P, Morrow EH (2010) The Sexually Antagonistic Genes of Drosophila melanogaster. PLoS Biol 8(3): e1000335. doi:10.1371/journal.pbio.1000335