Climatic niche similarity and geographic range limits in ecologically similar co-existing damselflies

Dear all,
Now it is time to discuss one of my papers again. Together with Keith Larson and Erik Svensson, I am currently working on a paper that investigates niche divergence in Calopteryx damselflies.

Speciation in the genus Calopteryx is largely thought to be de-coupled from ecology, and reproductive isolation seems to have evolved independent of habitat ecology, through sexual selection, social interactions, learning and/or genetic incompatibilities. For this reason, ecological differences between closely related odonates are a priori expected to be relatively minor, and the modest differences that exist are likely to have evolved post-speciation, reflecting ecological divergence after reproductive isolation was already achieved. We tested these predictions using a large habitat data set for the two largely co-existing species Calopteryx splendens and C. virgo in Sweden and Finland and then employed spatial modelling techniques to identify the:

(i) environmental habitat characteristics, amount of niche overlap and degree of habitat specialisation,

(ii) combined and interactive effects of environment and predators and

(iii) ecological differences between allopatric and sympatric populations.

It will be great to discuss our findings with you next week (as usual we meet on Wednesday the 6th of October at 10:15 at the Darwin room, Lund University). Erik has also suggested to read a recent paper by John E. McCormack, Amanda J. Zellmer, and L. Lacey Knowles. Their work focused on niche divergence and its role in speciation in Mexican Jays.

DOES NICHE DIVERGENCE ACCOMPANY ALLOPATRIC DIVERGENCE IN APHELOCOMA JAYS AS PREDICTED UNDER ECOLOGICAL SPECIATION?: INSIGHTS FROM TESTS WITH NICHE MODELS

I will circulate the Evolution paper by McCormack et al. (2010) and the manuscript via email. If I have not included you in the email list and you would like to read and comment on these papers, then please send an email Maren.Wellenreuther@zooekol.lu.se

I will bring fika to the next meeting.

Have fun, Maren

On intralocus sexual conflict in hermaphroditic animals

Former lab-member Jessica Abbott, who defended her PhD-thesis in Lund in 2006 has a review-paper published in Proc. R. Soc. Lond. B., that can be found here. After finishing her PhD, Jessica moved for a two-year postdoc to Adam Chippindale's lab at Queens University in Canada, and then back to Sweden and Uppsala University (Ted Morrow's lab).

Jessica will visit the Biology Department in Lund on October 14 for a Thursday Seminar in the "Blue Hall" (14.00, Thursday 14 October 2010). One possibility would be to read her review-paper on our lab-meeting that week (Thursday October 13, at 10.15) to prepare for her talk. Here is the abstract of Jessica's article in Proceedings:


Intra-locus sexual conflict and sexually antagonistic genetic variation in hermaphroditic animals

Jessica K. Abbott

Abstract

Intra-locus sexual conflict results when sex-specific selection pressures for a given trait act against the intra-sexual genetic correlation for that trait. It has been found in a wide variety of taxa in both laboratory and natural populations, but the importance of intra-locus sexual conflict and sexually antagonistic genetic variation in hermaphroditic organisms has rarely been considered. This is not so surprising given the conceptual and theoretical association of intra-locus sexual conflict with sexual dimorphism, but there is no a priori reason why intra-locus sexual conflict cannot occur in hermaphroditic organisms as well. Here, I discuss the potential for intra-locus sexual conflict in hermaphroditic animals and review the available evidence for such conflict, and for the existence of sexually antagonistic genetic variation in hermaphrodites. I argue that mutations with asymmetric effects are particularly likely to be important in mediating sexual antagonism in hermaphroditic organisms. Moreover, sexually antagonistic genetic variation is likely to play an important role in inter-individual variation in sex allocation and in transitions to and from gonochorism (separate sexes) in simultaneous hermaphrodites. I also describe how sequential hermaphrodites may experience a unique form of intra-locus sexual conflict via antagonistic pleiotropy. Finally, I conclude with some suggestions for further research.

Lab-meeting about selection, genetic drift and population divergence of a female mating polymorphism in diving beetles

This coming Wednesday (30 September 2010), we will discuss and give feedback on Tina Karlssons last manuscript: a study about population divergence of a female mating polymorphism in diving beetles and the relative role of genetic drift and selection. This paper is a study on three different species of diving beetles, all of which have the female mating polymorphism ("rough" and "smooth" females, respectively), but at various frequencies. Tina has studied population divergence in morph frequencies of these three species and compared with neutral molecular population divergence (AFLP-markers) to infer the relative roles of genetic drift, stabilizing selection and divergent selection in population divergence. This study is a follow-up study to the previous biomechanical study on male adhesion on these female morphs that we discussed at a  previous lab-meeting. 

Tina will send out this manuscript to interested participants on Monday. Please send her an e-mail (kristina.karlsson@zooekol.lu.se) if you have not received this manuscript by Monday and wish to participate in the discussion. Both positive and negative constructive feedback on this manuscript will be most welcome, as Tina will soon submit her thesis to the printer. The date of thesis defence will be Friday 26 November 2010, at 09.30, and the Faculty's opponent will be professor Nina Wedell from Exeter University (UK). 

Time and place for lab-meeting as usual: "Darwin" at 09.30, September 30 2010. Any fika-volunteer?

Are migrating birds using a "cactus corridor" in the Sonoran Desert?

This coming Wednesday (September 22) we will have two papers to discuss:

One by Tina that she will post separately, and one on a study that I did as part of my last post doc in Blair Wolf’s lab in New Mexico (http://biology.unm.edu/wolf/Home.html). Based on coinciding timing of Saguaro cactus bloom and bird migration in the Sonora we asked if migratory birds might fuel their journey northwards by exploiting flower nectar as energy and water source. From stable isotope analysis we concluded that Saguaro cacti provided food to the avian community mainly later in the season in the form of fruit and seeds. Nectar seems to be of less importance, and the idea of migrating birds following a nectar corridor on their way north has to be refuted, especially as mainly resident birds seem to profit from Saguaro as food resource.

I will send out the manuscript by email and you can also request it from me (Sophia.engel@teorekol.lu.se) if you did not receive it. I would be glad to receive your feedback, especially as this is a case of "negative results" that are often a little hard to communicate...

Time and place as usual: "Darwin", Wednesday 22 September at 10.15.

I’ll bring fika J

Seminar about conservation biology in South Africa on September 15

 

This coming Wednesday (15 September), PhD-student John Simaika from Stellenbosch University in South Africa will give a presentation about conservation biology entitled:

"Advances in monitoring and prioritizing riverine habitats for conservation using biotic indices with special emphasis on South Africa."

John is a PhD-student of Professor Mike Samways, who is head of the Department of Conservation Ecology and Entomology in Stellenbosch. Samways and his students have especially studied the conservation biology of rare, endemic and threatened odonates (dragonflies and damselflies) and developed various habitat restoration strategies to increase the population sizes of some rare species.

Prof. Samways and I have recently initiated a research collaboration and an exchange programme between Lund and Stellenbosch Universities, that was launched earlier this year and will run for the coming three years. John is here for a short visit as part of this programme. I will announce this seminar also to people outside our lab-group. Time and place as usual:

"Darwin" on September 15, 10.15.

Please spread the word about this talk to all other interested students and researchers in the Ecology Building!

Surviving in academia: Young, dumb and full of dung

I wanted to share an article I read recently on todays scientific culture and how this reflects on young scientists.

As a "young" scientist I found the article of extreme interest, as it highlights much of my limited view of the system I hope to join. It taps into the general feeling of being considered (and perhaps feeling) inadequate based on your publication rate and eventually forced into publishing anything and everything you can, in the vain hope that you can carve out a meaningful career or at least not have to get a real job.

But what really struck me most was the authors comparison with a young Darwin, and the time he spent nurturing his ideas without the necessity to publish them into bite size portions. Of course much has changed and the birth of "big science" can be considered a hugely positive step in its advancement of ideas, but it does highlight a need for us up-and-coming whippersnappers to take the time to absorb and digest ideas, rather than just spitting out whatever we feel we can publish.

Lab-meeting on female mating polymorphisms in diving beetles

This coming Wednesday (8 September), we will discuss a manuscript by Kristina Karlsson that is part of her PhD-thesis, which will be defended on November 26, later this autumn. Both Tina and I would like to receive feedback on this manuscript before it is included in the thesis. The paper is a study which combines the field of sexual conflict with experimental biomechanics, and it has been done in collaboration with morphologist and entomologist professor Stas Gorb at Kiel University in Germany. 

Tina has investigated male adhesion on the surface of two female morphs in diving beetles: either "smooth" or "rough" female types. This polymorphism in female morphology is thought to be an adaptation against male mating harassment, similar to the one we have previously studied in the damselfly Ischnura elegans, which also has multiple female morphs co-existing within local populations.

Tina will send out the manuscript on Monday so that you can read it well in advance and be prepared for the lab-meeting. In case you do not receive it, send an e-mail to Tina (kristina.karlsson@zooekol.lu.se) and ask for a copy.

Time and place as usual: "Darwin", Wednesday 8 September at 10.15. Any fika volunteer?