Research Areas

 

Comparative Genomics and Social Evolution in Bees and Wasps


The evolution of eusociality from solitary life is considered one of the major transitions in evolution.  By studying how this transition occurred using genomic approaches, we seek to answer: 1) What types of genetic changes accompany a major transition in evolution—changes in gene number, sequence, or regulation?  2) Are these changes relatively minor or large-scale?  3) Are there shared, core sets of genes (i.e. a “genetic toolkit”) or are there many genetic avenues to eusocial life?

Multiple origins of sociality (indicated in red) and small genome size in the insects make them especially good models for comparative genomics. 


We have recently sequenced the first social wasp genome Polistes dominula, and are conducting comparative analysis to other social insect genomes, in collaboration with the laboratory of Volker Brendel (Indiana University).

Paper wasps as a Neurogenomic Model for Complex Behavior


Animal behavior stems from genetic and environmental influences over the lifetime of an organism.   Paper wasps in the genus Polistes are an especially attractive model for studying the roles of genetics, epigenetics, and the social environment in shaping behavior.  These insects are eusocial, but retain some characters in common with solitary ancestors, such as well-developed maternal behavior, making them a promising model for understanding the evolution of several fascinating, complex behaviors such as maternal care, cooperation, aggression, and individual recognition.


 

Using transcriptomic (RNA-seq and microarray) data from paper wasps, in comparison to studies from other social insects, we explored whether the same or different genes underlie the convergent evolution of one of the defining traits of eusociality, the presence of castes (e.g. figure to the right). 

    Our studies point to a small set of deeply conserved pathways and gene networks that are related to the convergent evolution of queen and worker castes across ants, bees, and wasps. 

    Furthermore, our data suggest that nutritional differences and molecular pathways related to nutrient signaling and metabolism are key regulators of social caste differences in wasps, and this may be widely conserved across social insects.

Ongoing research investigates the epigenetic basis of sociality in paper wasps.  Interestingly, there has been a dramatic reduction of the DNA methylation system in Polistes compared to all other known social insects, suggesting surprising lability of epigenetic influences on social phenotypes in the insects.


Polistes fuscatus (left) shows variation in facial color patterns, P. metricus (right) does not.  Unusual interspecies nest-sharing photo by Jenny Jandt.

In addition, we are untangling the influences of nutrition and maternal behavior on offspring development.  Maternal vibrational cues can be simulated in the field using the devices shown at above (photos by Jenny Jandt), in collaboration with Bob Jeanne and John Hermanson (University of Wisconsin).



Polistes wasps are the only insects, and one of the few animals, known to possess individual facial recognition. 

We are using a combined candidate gene and transcriptomic approach (using RNA-sequencing), and manipulations of gene expression (using RNA-interference) to provide the first studies of the molecular underpinnings of facial recognition in any animal.  In collaboration with Elizabeth Tibbetts (University of Michigan).

Integrative Ecological, Physiological, and Genomic Analyses of Bee Health


Both managed honey bees and wild native bees are beneficial insects with a critical role in agricultural pollination.  There have been startling declines in bee populations in recent years, one example being honey bee “Colony Collapse Disorder”.  Pollinator health problems have been tied to habitat disturbance and the availability of adequate floral resources.  We are interested in understanding the role of bee nutrition on bees’ susceptibility to pathogens, abundance in different habitats, and overall health.



We are testing the hypothesis that nutritional stress and infection with viruses leads to colony abandonment by worker bees.  In collaboration with Bryony Bonning and Allen Miller (Iowa State University), we are testing this idea using an integrative approach combining virology, physiology, genomics, and behavioral studies.

 

We are also investigating how landscape composition (i.e. extent of agricultural intensification) and vegetation composition affect bee abundance and nutrition. 


We have worked in different agro-ecosystems, including grazing lands (in collaboration with Diane Debinski) and soybean fields (in collaboration with Matt O’Neal). 


Data thus far suggest nutritional state of managed honey bees and native bees can bee affected by the type of landscape bees live in, with extremely high levels of grazing and agricultural intensification resulting in poorer bee nutritional state.

Word Cloud by Tagxedo.com