University of Minnesota
University of Minnesota
College of Biological Sciences
http://www.cbs.umn.edu/

Departmental seminars

All Ecology, Evolution and Behavior departmental seminars are held Wednesdays at 3:30 pm in 335 Borlaug Hall unless otherwise noted.

 

Spring 2012

Jan 25

Comparative sociogenomics of bees and wasps: insights into social evolution

Dr. Amy Toth, Iowa State University

In the Toth lab, we study the evolution of sociality and mechanisms underlying complex social organization in insects.  Our work focuses on eusocial colonies of bees and wasps, whose highly integrated societies exhibit a bewildering complexity of individual and colony-level behaviors. We use an integrative research approach involving field studies of naturally occurring colonies, experimental manipulations in semi-natural or lab settings, and numerous lab techniques to measure physiological, chemical, and genetic characters of individual insects. We have applied next generation sequencing methods to develop sequence databases for social wasp species, in order to facilitate comparative evolutionary analyses.

Host: Dr. Emilie Snell-Rood

Feb 1

Ecology from the ground up:  A roots-to-biomes look at mycorrhizal symbiosis

Dr. Kabir Peay, University of Minnesota

Ecology has made great progress in recognizing the importance of positive interactions in structuring natural communities and in elucidating the contribution of microbial organisms to ecosystem function. However, fundamental questions remain unanswered about the ecology of even the most common forms of symbiosis. My research focuses on plant-fungal root associations, better known as mycorrhizas, which constitute one of the most pervasive mutualisms in terrestrial ecosystems.  I work on questions at multiple scales of this symbiosis in order to try and build a roots-to-biomes understanding of plant-microbe symbiosis.

Host: Dr. Jeannine Cavender-Bares

Feb 8

"Bacterial communities in the gut of pigs: effects of age, antibiotics, and infection on community compositions"

Dr. Dick Isaacson, University of Minnesota

Bacterial communities in the gastrointestinal tract of animals have been recognized as important drivers of animal maturation and health. It is estimated that the gut microflora contains 10e14 individual bacteria and its composition is between 500 and 1000 species. The gut microflora is known to have important functions for animals including promoting the maturation of the immune system and  contributing metabolic functions to the host. We have been using culture independent characterize the bacterial composition of the pig intestinal tract. Data will be presented regarding the composition of the pig gut microbiome and how it changes over time. This work also demonstrates that pen mates have similar but not identical gut microbiomes. In addition, data will be presented that demonstrate the reproducible alterations of the pig gut microbiome when they consume growth promoting antibiotics. Finally, data will be presented that demonstrate that concurrent infections have profound effects on the gut microbiome including pathogen:pathogen interactions.

Host: Dr. Elizabeth Borer

Feb 15

Socialized Medicine in Honey Bee Colonies

Dr. Marla Spivak, University of Minnesota

Honey bees, Apis mellifera, are highly social insects that live in large colonies (e.g., 40,000 individuals). One cost of social living is the increased rate of disease transmission among individuals. One effective strategy of honey bees and other social insects to combat pathogens and parasites has been the evolution of “social immunity” – colony-level defenses that emerge from the collective behaviors of individuals.  One form of social immunity in honey bees is hygienic behavior in which individual bees detect and remove diseased and parasitized brood from the nest, reducing colony-level infection. Another form is the collection of plant resins by some bees and the incorporation of the antimicrobial resins into the nest architecture as propolis.  I will discuss our research on these forms of honey bee social immunity, and our current outreach efforts to translate this research directly to beekeepers and bee breeders with the goal of improving honey bee health nationwide.

(A recording of this seminar is available to CBS students, faculty and staff only.  To obtain access, please email schu1293@umn.edu.)

Host: Dr. Emilie Snell-Rood

Feb 22

“The eternal seas of space and time”: Experimental evolution in structured communities"

Dr. Ben Kerr, University of Washington

At their core, biological systems involve interaction.  From molecular to ecosystem scales, critical biological processes entail close physical proximity of the relevant entities (whether these are molecules, cells, organisms, etc.).  Therefore, it is essential to understand the manner in which such entities come together.  In this talk, I focus on the effects of limited movement for the evolutionary trajectories of organisms in various ecological scenarios.  Because the nature of dispersal and migration affects who interacts with whom, patterns of movement within a community can influence eco-evolutionary dynamics.  I illustrate this using microbes evolving inside experimental metapopulations.  I discuss how the topology of migratory connections between subpopulations affects (1) basic evolutionary search of adaptive landscapes, (2) the evolution of virulence in host-pathogen communities, and (3) the evolution of altruistic restraint in competitive relationships.  In these cases, the spatial scale of migration influences both evolutionary outcomes and spatio-temporal dynamics of the community.

(A recording of this seminar is available to the public.  Please email schu1293@umn.edu if you experience issues accessing this video.)

Host: Dr. Emilie Snell-Rood and Philosophy Dept.

Feb 29

Invasion Biology: The Science and the Ideology

Dr. Mark Davis, Macalester

The science of invasion biology has been shaped by both data and values.   When the field of invasion biology began in the early 1980s, all non-native species were characterized as ‘invaders’ by most researchers.  By choosing the invasion paradigm, ecologists brought not just data but a specific value-based agenda to the public, conservation organizations, and policy makers.  In many cases, policy and conservation decisions regarding non-native plant species have not been based on good scientific evidence but on assumptions of harm, beliefs that were rooted in a nativism ideology that had been promulgated by scientists.

Host: Dr. Alex Eilts

Mar 7

The Spread of Homo Out of Africa at 1.8 myr: Evidence from the fossil faunas at the Dmanisi Site in country of Georgia

Dr. Martha Tappen, University of Minnesota

The first major “Out of Africa” biogeographic expansion in human evolution occurred long before the evolution of modern humans at about 1.8 million years ago.  The Dmanisi site in the country of Georgia has some of the best preserved and earliest evidence for this expansion in the form of Homo erectus and other mammal fossil bone and stone tools.  This presentation will focus on the evidence from Dmanisi and specifically the evidence from the mammalian fossils for how this large site formed; the degree of interaction between Homo and the fossil mammals present at the site; and what the site indicates for the many hypotheses that have been proposed to explain “Out of Africa I”.  Evidence indicates that the site formed because it was located in a cul-de-sac and had low elevation promoting rapid burial.  Carnivore activity is more prevalent than hominin meat-eating activities.  Hominins did not spread with a major expansion of other African mammals, and the habitats were probably significantly different that African habitats.  This suggests hominins had in fact changed their adaptive strategies at this time.  The hominins were eating meat, although signs carnivore consumption of animals is more commonly preserved on the bones.  Other changes in behavior are hinted at by the evidence, but more work is needed.

Host: Dr. Mike Wilson

Mar 21

Resource Dynamics and the Evolution of Bright Colors: Insights from Butterflies

Dr. Nate Morehouse

Color patterns don’t take up physical space in the same way that deer antlers or peacock tail feathers do, but they can still impose strong resource costs. This is because color production often requires large quantities of specific pigment molecules, which may be rare in diet or metabolically expensive to produce. These material requirements can introduce strong biochemical biases into the resource budgets of individuals, resulting in important evolutionary relationships between color patterns and underlying trophic dynamics. Dr. Morehouse will be speaking about his research on the role of nitrogen limitation in the evolution of color signaling in the Cabbage White butterfly, Pieris rapae , and how tryptophan toxicity may have influenced the evolution of a seasonal color polyphenism in the European Map butterfly Araschnia levana.

(A recording of this seminar is available to CBS students, faculty and staff only.  To obtain access, please email schu1293@umn.edu.)

Host: Dr. Emilie Snell-Rood

Mar 28

Phenotypic plasticity, evolvability, and the stability of quantitative genetic patterns

Dr. Mike Whitlock, University of British Columbia

Phenotypic plastic genotypes express different phenotypes in different environments, often in adaptive ways. The evolution of phenotypic plasticity creates developmental systems which are more flexible along the trait dimensions which are more plastic, and as a result, we hypothesize that such traits will express greater mutational variance, genetic variance, and evolvability. We developed an explicit gene network model with three components: some genes can receive environmental cues about the adult selective environment, some genes which interact repeatedly to determine each others’ final state, and other genes which translate these final expression states into the phenotype.

Host: Dr. Emilie Snell-Rood

Apr 3

SPECIAL TUESDAY SEMINAR

Plant Populations in a changing world

Dr. Helen Alexander, University of Kansas

 (A recording of this seminar is available to CBS students, faculty and staff only.  To obtain access, please email schu1293@umn.edu.)

Host: Dr. Ruth Shaw and Plant Biology

Apr 11

Molecular Adaptation to Seasonal Change in Hibernating Mammals

Dr. Matt Andrews, University of Minnesota Duluth

Hibernation is a natural adaptation that allows certain mammals to survive physiological extremes that would result in death in humans.  The fundamental trait present in natural hibernators is greatly reduced body temperature, metabolism and respiration—conditions that buy precious time in cases of myocardial ischemia, traumatic injury and cardiac arrest.  High-throughput instrumentation and advances in computational power have allowed us to identify genes that control the hibernation phenotype and link their expression to organ function under extreme conditions.  We have identified genes that are expressed in active and hibernating thirteen-lined ground squirrels (Ictidomys tridecemlineatus) at six points throughout the year by high-throughput cDNA sequencing using the Roche 454 and Illumina sequencing systems.  The 454 platform generates individual reads with lengths up to 500 bases and the Illumina High-Seq system produces 10 million reads per reaction.  These massive sequencing platforms have generated statistically high numbers of cDNA sequences that are used to determine patterns of gene expression throughout the hibernation season.  This new approach of measuring gene activity opens the door for investigating other novel phenotypes in the vast world of “non-model” organisms.

Host: Dr. Emilie Snell-Rood

Apr 18

Dissecting an evolutionary radiation: exploring leaf shape diversity in Pelargonium

Dr. Carl Schlichting, University of Connecticut

The plant genus Pelargonium is species-rich (~250 species) and extraordinarily morphologically diverse, with strong variation in growth forms, floral characters and leaf shape. Our work is focused on examining patterns of evolution of leaf shape and functional traits in this genus, taking advantage of the phylogenetic and biogeographical history of its members.
I will report on studies examining character evolution, phenotypic plasticity and trait integration, and how this work fits into our current Dimensions of Biodiversity project.

(A recording of this seminar is available to CBS students, faculty and staff only. To obtain access, please email schu1293@umn.edu.)

Host: Dr. Emilie Snell-Rood

Apr 24

SPECIAL TUESDAY SEMINAR

The Evolutionary Ecology of Geographic Range Limits

Dr. Amy Angert, Colorado State University

(A recording of this seminar is available to CBS students, faculty and staff only. To obtain access, please email schu1293@umn.edu.)

Host: Dr. Ruth Shaw and Plant Biology

May 2

Individual differences in behavior in threespined sticklebacks

Dr. Alison Bell, University of Ilinois

Threespine sticklebacks are small fish renowned for their geographic variation among populations. Even within populations, however, individual sticklebacks show dramatic inter-individual differences in behavior. For example, some sticklebacks are consistently more ‘bold’ in the presence of a predator compared to others, and individuals that are more ‘bold’ toward a predator are also more aggressive toward other sticklebacks We study the proximate causes and ultimate consequences of behavioral variation among individuals and populations of sticklebacks. In this talk, I will describe some of the other axes of behavioral variation that we observe in sticklebacks, including consistent individual differences in parenting behavior and in how individuals respond to a changing food resource. I will illustrate some of the approaches we are taking to understand the factors that can maintain behavioral variation, as well as its underlying causes using, for example, whole genome expression analyses.

(A recording of this seminar is available to CBS students, faculty and staff only. To obtain access, please email schu1293@umn.edu.)

Host: Dr. Emilie Snell-Rood