Labmeeting on niches and sexual communication in antbirds

Posted by Erik Svensson

The next weeks lab-meeting we will discuss some classical problems in ecology and evolution namely niche evolution, reproductive character displacement (or the lack thereof) and sexual communication. I have chosen a recent article on a South American bird radiation in Nature, co-authored by our Lund colleague Charlie Cornwallis and another paper on the same topic in PNAS by the same Oxford group (Joseph A. Tobias and Nathalie Seddon).

The titles and Abstracts of both these papers are found below, where you can also find link to these papers. Charlie has promised that he will be present to answer any more specific questions we might have on the results, the analyses and other background information about this fascinating system.

When: Tuesday February 4 at 10.30
Where: "Argumentet", 2nd floor (Ecology Building)

Species coexistence and the dynamics of phenotypic evolution in adaptive radiation 

Joseph A. Tobias, Charlie K. Cornwallis, Elizabeth P. Derryberry, Santiago Claramunt, Robb T. Brumfield & Nathalie Seddon

Nature (2013) doi:10.1038/nature12874

Interactions between species can promote evolutionary divergence of ecological traits and social signals, a process widely assumed to generate species differences in adaptive radiation. However, an alternative view is that lineages typically interact when relatively old, by which time selection for divergence is weak and potentially exceeded by convergent selection acting on traits mediating interspecific competition. Few studies have tested these contrasting predictions across large radiations, or by controlling for evolutionary time. Thus the role of species interactions in driving broad-scale patterns of trait divergence is unclear. Here we use phylogenetic estimates of divergence times to show that increased trait differences among coexisting lineages of ovenbirds (Furnariidae) are explained by their greater evolutionary age in relation to non-interacting lineages, and that—when these temporal biases are accounted for—the only significant effect of coexistence is convergence in a social signal (song). Our results conflict with the conventional view that coexistence promotes trait divergence among co-occurring organisms at macroevolutionary scales, and instead provide evidence that species interactions can drive phenotypic convergence across entire radiations, a pattern generally concealed by biases in age.

Species interactions and the structure of complex communication networks

Joseph A. Tobias, Robert Planqué, Dominic L. Cram, and Nathalie Seddon

Abstract

A universal challenge faced by animal species is the need to communicate effectively against a backdrop of heterospecific signals. It is often assumed that this need results in signal divergence to minimize interference among community members, yet previous support for this idea is mixed, and few studies have tested the opposing hypothesis that interactions among competing species promote widespread convergence in signaling regimes. Using a null model approach to analyze acoustic signaling in 307 species of Amazonian birds, we show that closely related lineages signal together in time and space and that acoustic signals given in temporal or spatial proximity are more similar in design than expected by chance. These results challenge the view that multispecies choruses are structured by temporal, spatial, or acoustic partitioning and instead suggest that social communication between competing species can fundamentally organize signaling assemblages, leading to the opposite pattern of clustering in signals and signaling behavior.

Lab Meeting about Research Careers and Reputation

Posted by Anna Nordén

Hello everyone,

For the next meeting, I thought we could discuss research careers and reputation in science. The first short article is about how to build and maintain a scientific reputation with ten simple rules. The other one is a quantitative study about the difference between PhD students’ preferences for making a career in either academia or industry. I thought we could focus on their findings, that PhD students staying in academia have a stronger ‘taste for science’. 

Do you agree with the ten simple rules or are there more ‘rules’ that should have been included? What does it actually mean to have a stronger or weaker ‘taste for science’?

Tuesday 28/1 at 10:30 – 12 in Argumentet as usual and I will provide fika.

I’m looking forward to hear about your experiences and opinions on this topic!

Article 1:
Ten Simple Rules for Building and Maintaining a Scientific Reputation

By Philip E. Bourne, Virginia Barbour

Article 2:
A taste for science? PhD scientists’ academic orientation and self-selection into research careers in industry

By Michael Roacha, Henry Sauermann

Abstract
Recent research on industrial and academic science draws on the notion that academically trained scientists have a strong “taste for science”. However, little attention has been paid to potential heterogeneity in researchers’ taste for science and to potential selection effects into careers in industry versus academia. Using survey data from over 400 science and engineering PhD students, we examine the extent to which PhD students’ taste for science (e.g., desire for independence, publishing, peer recognition, and interest in basic research) and other individual characteristics predict preferences for research careers in industry versus academia. Our results suggest that PhD students who prefer industrial employment show a weaker “taste for science”, a greater concern for salary and access to resources, and a stronger interest in downstream work compared to PhD students who prefer an academic career. Our findings have important implications for innovation research as well as for managers and policy makers.

Lab meeting: Abundant Genetic Variation + Strong Selection = Multivariate Genetic Constraints: A Geometric View of Adaptation

By Tom Gosden

Hello all. Erik has asked me to pick a paper as a way of integrating me back into the lab and meeting all the new faces that have appeared over the last 5 years I have been away. So to ease into it I have picked a paper which I found very useful in explaining and interpreting multivariate genetic constraints.  It was written several years ago by Bruce Walsh and Mark Blows. It might be considered quite heavy in places, but I have personally found it an excellent paper as an introduction to some very complex and interesting approaches to studying genetic constraints.

There will be a test.


Abundant Genetic Variation + Strong Selection = Multivariate Genetic Constraints: A Geometric View of Adaptation
Bruce Walsh and Mark W. Blows

Abstract
Evolutionary biology has struggled to explain the coexistence of two basicobservations: Genetic variation is found in almost all traits in the presenceof strong natural and sexual selection in natural populations. These twoobservations are in direct conflict as such selection should deplete geneticvariation. Furthermore, the presence of genetic variation in a trait, and se-lection acting on that trait, is often not sufficient for the trait to respondto selection. Here, we bring together geometric perspectives on mutation,selection, and genetic variation and show how the perceived incompatibilitybetween these two observations is a consequence of taking a trait-by-traitapproach to the multivariate problem of genetic variation and selection. Weconclude that the simultaneous presence of widespead genetic variation in,and strong selection on, individual traits indicates that substantial multivari-ate genetic constraints are likely to be present in natural populations 

A revival for Jean Baptiste Lamarck?

 

Posted by Erik Svensson

The latest issue of the journal Nature Neuroscience has the famous French evolutionary biologist Jean Baptist Lamarck on its cover. This is of course quite an unusal cover for a journal which is rather mechanistically oriented, and the reason is probably an article by Brian K. Dias and Kerry J. Ressler entitled "Parental olfactory experience influences behaviour and neural structure in subsequent generations."  The claim made in this article, as well as implied by the choice of journal cover and in the "News & Views"-article by Moshe Shyf is that Lamarck's old but generally outdated theory of inheritance of aquired characters might be true after all, and the central dogma of molecular biology (that genes influence the phenotype but not vice versa) might be wrong.

Extraordinary claims requires extraordinary evidence, and I think it would be useful to critically discuss this paper at this semester's first lab-meeting, which will take place in "Argumentet" (2nd floor, Ecology Building) on January 14 at 10.30.

Undoubtedly, some rather pompous proponents of a so-called "Extended Evolutionary Synthesis" (EES) will probably welcome this study in their endless battle against the so disliked "Neodarwinian Synthesis", which I personally prefer to call "The Modern Synthesis" and so does population geneticist Jerry Coyne.  

These endless, but often futile calls for "paradigm shifts" and "scientific revolutions" have been heard for many years, but have never been very succesful and appears to me to be more ideologically motivated than grounded in scientific advancements based on new theory or experimental results. A particularly enthusiastic proponent of the ESS, Massimo Piggliucci, has, however, seemed to have given up empirical evolutionary biology and moved on to philosophy instead, perhaps because the anticipated "revolution" did not happen the way he anticipated that it would? 

In any case, Massimo probably enjoys philosophy more than biology (no empirical evidence needed that complicates things) and hopefully he has a lot to think about, given that he has three PhD-exams with him (in genetics, evolutionary biology and philosophy). As you can hear, I am sceptical.

You can hear that I largely agree with Jerry Coyne on the likelihood and validity of a forthcoming "scientific revolution", and I think those who call for this suffer from the so-called BIS - Big Idea Syndrome. Moreover, scientific revolutions do not happen because you want them. To quote Richard Lewontin, Jerry Coynes former PhD-advisor who states critically the following about scientific revolutions:

“The so-called evolutionary synthesis – these are all very vague terms. . . . That’s what I tried to say about Steve Gould is that scientists are always looking to find some theory or idea that they can push as something that nobody else ever thought of because that’s the way they get their prestige. . . .they have an idea which will overturn our whole view of evolution because otherwise they’re just workers in the factory, so to speak. And the factory was designed by Charles Darwin.”

Articles to discuss at lab-meeting (click on links): 

    Dias & Ressler

    Szyf