Andrew Storfer
(Washington State University)

09/5/19, 13:30 - 14:30 at Room 3631 (6th floor of building 3 of the Faculty of Sciences)

merging infectious diseases threaten wildlife, livestock and humans, and are recognized as a leading scientific challenge for the 21st Century. Emerging infectious diseases are implicated in the global die-offs of amphibians, driving populations and even species to extinction. Two critical questions arise when pathogens emerge. First – is the pathogen new or old? Second – why is the disease spreading? I will discuss the past 10 years of a multifaceted research program on coevolution of tiger salamanders and an emerging virus throughout western North America to address these two questions. Using comparative phylogenetic methods we show that tiger salamanders and viruses are coevolved, but human introductions of infected salamanders as fishing bait disrupts coevolutionary patterns. Due to increased densities of captive populations, increased virulence is observed in a virus strain isolated from a captive salamander population. Next, we show geographic variation in putative viral virulence genes. Using a cross-infection experiment designed to test for local adaptation, we show that apparent viral adaptation is inversely correlated with the strength of selection on these genes. Finally, we are using microarrays to unravel the genomic basis for the high susceptibility of tiger salamanders to the virus. We show a general lack of adaptive immunity, which may be associated with the high lethality of the virus.

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