Friday, April 29, 2016

Lab meeting on female mate choice

Posted by Katrine Lund-Hansen

I thought this week we could read a paper by one of the invited speakers at Evolution in Sweden 2016, Sergey Gavrilets. There are many papers to choose from, so I tried to pick one that should be of general interest, even though it is a quantitative genetic model. So nothing about flies this time :)

Time: May 3rd, 10:00
Where: Argumentet, Ecology Building 2nd floor
Cake: Of course!

Title: The evolution of female mate choice by sexual conflict

Abstract: Although empirical evidence has shown that many male traits have evolved via sexual selection by female mate choice, our understanding of the adaptive value of female mating preferences is still very incomplete. It has recently been suggested that female mate choice may result from females evolving resistance rather than attraction to males, but this has been disputed. Here, we develop a quantitative genetic model showing that sexual conflict over mating indeed results in the joint evolution of costly female mate choice and exaggerated male traits under a wide range of circumstances. In contrast to traditional explanations of costly female mate choice, which rely on indirect genetic benefits, our model shows that mate choice can be generated as a side–effect of females evolving to reduce the direct costs of mating.

Monday, April 25, 2016

Half-time seminar on hermaphrodites and sex chromosome evolution

Posted by Anna Nordén

Hi all,
In addition to the lab meeting tomorrow (April 26th), I will have my half-time seminar in the afternoon entitled:

"Sex Chromosome Evolution & Sexual Antagonism in Hermaphrodites"

Time and place: 14:30, Red Room, Ecology Building.


The opponent will be Dr. Helena Westerdahl, MEMEG.

Everyone is welcome!

Thursday, April 21, 2016

Talk by Viktor Nilsson-Örtman on life-history theory, temperature and metabolic scaling (April 26 2016)



Next week, EXEB postdoc Viktor Nilsson-Örtman will give a talk about his PhD-research at Umeå University and his subsequent  research at Toronto University (Canada), where he has been a VR-funded postdoc in the laboratory of Locke Rowe. Although Viktor primarily studies damselfly larvae, the topic is a very general one that should be of interest to most EXEB members.

When: Tuesday, April 26, 2016
Where: "Argumentet", 2nd floor (Ecology Building)

 Beyond the log-log plot: toward a life history theory of metabolic scaling

Allometric scaling rules are common in biology, but it remains unclear to what extent they reflect fundamental biophysical constraints or natural selection. Two famous examples are the mass-scaling of metabolism (Kleiber’s law) and the temperature-scaling of biological rate traits (the Universal Temperature Dependence). One problem with studies of biological scaling is that they have been performed at the between-species level, even though natural selection can only act within species. By sampling European and North American damselflies over continental scales and performing common garden experiments within a quantitative genetic framework, my work has revealed striking - but previously unrecognized - variation in the size- and temperature-scaling of growth and metabolism at the level where natural selection can act. In addition, through common garden experiments, I have tried to understand the consequences of this variation with respect to ecological interactions, environmental variability and species’ life histories. In this talk, I will try to summarize the main findings from my recent and ongoing work on these topics.

Thursday, April 14, 2016

Discussion on vertebrate diversity

Hello all! For next week's lab meeting we will discuss a paper entitled: "Explaining large-scale patterns of vertebrate diversity" by John Wiens.

Link to paper: http://rsbl.royalsocietypublishing.org/content/11/7/20150506

Thursday, March 31, 2016

Lab meeting about sex chromosomes and dosage compensation in vertebrates

Posted by Anna Nordén

Next time at the lab meeting (Tuesday, April 5th) we will discuss a review by Jennifer Marshall Graves about the evolution of vertebrate sex chromosomes with an emphasis on the variation and similarity of dosage compensation mechanisms in vertebrate clades. How it works, how it might have evolved, and general patterns.

Looking forward to a fruitful discussion. Time (10 am) and place (Argumetet) as usual.

Title: Evolution of vertebrate sex chromosomes and dosage compensation

Abstract: Differentiated sex chromosomes in mammals and other vertebrates evolved independently but in strikingly similar ways. Vertebrates with differentiated sex chromosomes share the problems of the unequal expression of the genes borne on sex chromosomes, both between the sexes and with respect to autosomes. Dosage compensation of genes on sex chromosomes is surprisingly variable — and can even be absent — in different vertebrate groups. Systems that compensate for different gene dosages include a wide range of global, regional and gene-by-gene processes that differ in their extent and their molecular mechanisms. However, many elements of these control systems are similar across distant phylogenetic divisions and show parallels to other gene silencing systems. These dosage systems cannot be identical by descent but were probably constructed from elements of ancient silencing mechanisms that are ubiquitous among vertebrates and shared throughout eukaryotes.

Monday, March 21, 2016

Talk on Climate Change and Thermal Adaptation by Michael Logan on 29/3

Posted by Katie Duryea

Next week my grad student friend and academic brother, Mike Logan will be in the area and has agreed to give a talk at our EXEB meeting (Weizhao has nicely agreed to switch to the 17/5 meeting so we could use his spot.).

Mike is currently an NSF postdoctoral fellow at Stellenbosch University in South Africa. He does exiting work on thermal biology, thermal adaptation, and its relevance to climate change. Most of his work has been with lizards but he has been involved in some recent projects with insects, so I think his work will be interesting and relevant to all of us. More details about Mike can be found on his website:
www.evolutioninthetropics.com

Below is an abstract for his talk. The talk will be about 30 minutes with plenty of time for discussion. All are welcome!

When: Tues, 29 Mar, 10:00
Where: Argumentet
What: Talk, Discussion, Fika 

Anolis lizard in Honduras. Photo by Mike Logan.

Abstract:
The myth of the porcelain population: are we overestimating extinction risk by underestimating the power of evolution?

Models that explore the impact of climate change at global scales predict that terrestrial ectotherms are especially prone to extinction. But in order to evaluate many species and generate broad conclusions, global models must sacrifice data resolution. In the push for sweeping generalities, is it possible that these models ignore important adaptive features of real populations? In this talk, I will use data from New World reptiles and Old World insects to argue that in situ adaptive processes will significantly reduce the negative effects of rapid environmental change for many, if not most, species. 



Thursday, March 17, 2016

Lab meeting on multicellular origins

Posted by Hanna Laakkonen

Spring is here and I felt like reading something a bit different, so for the next weeks lab meeting I picked a review on the origins of multicellularity in Volvox communities. But don't worry, perhaps we can keep the discussion on more general level about evolutionary transformations and not dig ourselves into the details of Volvox signaling pathways ;-). I'll bring fika!

When: Tues, March 22nd, 10:00
Where: Argument

Ted Kinsman / Photo Researchers / Universal Images Group

Origins of multicellular complexity: Volvox and the volvocine algae

Matthew D. Herron





Abstract
The collection of evolutionary transformations known as the ‘major transitions’ or ‘transitions in individuality’ resulted in changes in the units of evolution and in the hierarchical structure of cellular life. Volvox and related algae have become an important model system for the major transition from unicellular to multicellular life, which touches on several fundamental questions in evolutionary biology. The Third International Volvox Conference was held at the University of Cambridge in August 2015 to discuss recent advances in the biology and evolution of this group of algae. Here, I highlight the benefits of integrating phylogenetic comparative methods and experimental evolution with detailed studies of developmental genetics in a model system with substantial genetic and genomic resources. I summarize recent research on Volvox and its relatives and comment on its implications for the genomic changes underlying major evolutionary transitions, evolution and development of complex traits, evolution of sex and sexes, evolution of cellular differentiation and the biophysics of motility. Finally, I outline challenges and suggest future directions for research into the biology and evolution of the volvocine algae.http://onlinelibrary.wiley.com/doi/10.1111/mec.13551/pdf