Introduced white pine sawfly: ​​Diprion similis

Meet my study system!
Diprion similis is known as the introduced white pine sawfly in North America, and the name tells you most of what you need to know about why they are so interesting. D. similis' native range is in the old world, stretching from western Europe across to eastern Russia, where it feeds primarily on the abundant Scotch pine (Pinus sylvestris) throughout. 

In 1914, the first records of D. similis in North America were recorded in Connecticut. Since then, the species has spread across most of northeastern North America, but - as its name suggests - is now most often found on Eastern White Pine (Pinus strobus), which is native to North America and has drastically thinner needles than any native host. 

​The focus of most of my postdoctoral work is investigating the evolutionary history of this invasion and shift to a novel host, using both modern and historical specimens. My work intersects a variety of fields and approaches, including population genomics, "museomics", evolutionary ecology experiments, and morphometrics. 

Current research projects

Read below to get to know some of the projects I have been working on recently, also see publications

Sampling locations and pine host for population genomic sequencing.

Population structure and demographics of an invasion

In this project - funded by The American Genetics Association's EECG award - I am using whole genome sequencing to identify discreet populations within eastern North America, and use demographic analysis to estimate number of invasions, genetic variation, and more. Read more about this project HERE.

Preserved D. similis from the Canadian National Collection.

 Historical genomics
​+ morphometrics

Insect collections offer powerful insights into the history of insects, especially for invasives. Using both morphometrics and museum genomics tools, I am uncovering the genetic and morphological history of a successful invasion and subsequent host shift. 

Change in D. similis preference for white pine over time.

Evolution of a host preference in an introduced range

An outstanding question in host adaptation is whether host-preference or host-performance is more likely to evolve first during successful host-shifts. Using both historical survey data as well as contemporary experiments, I aim to address this question on D. similis' shift to white pine in the last century. 

Drosophila work

Adaptation to divergent environments in the D. americana ​group

The Drosophila americana group occupies a diverse range of environments in North America. I investigated if differences in environmental variables is correlated with adaptive traits such as pigmentation and desiccation resistance. Read more HERE.

Cuticular hydrocarbon divergence and reproductive isolation

Cuticular hydrocarbons (CHCs) are important as sensory signals in the form of pheromones in Drosophila. Divergence in these pheromones could be critical in dictating patterns of sexual isolation. I used mating trials, chemical analysis, and perfuming experiments to evaluate this claim. Read more HERE.​

Caribbean Drosophila pigmentation
​and parasitoids

The Drosophila dunni clade consists of West Indies island endemics with unique pigmentation patterns on each island. We hypothesized that pigmentation was being used as protection against parasitoid wasps and surveyed these islands for both flies and wasps. Read more about our voyage HERE.​