Current Lab Members

Post Docs

Ariel Greiner

I am a quantitative ecologist focused on using modelling to inform conservation and health solutions. I am also passionate about increasing equity, diversity and inclusion in science and beyond. Currently, I am a postdoctoral fellow in the Shea and Ferrari Labs working on developing mathematical and statistical models of foot-and-mouth disease virus and methods to optimize the deployment of surveillance to manage epidemiological and ecological systems. Before starting my postdoc at Penn State, I obtained a PhD in Ecology and Evolutionary Biology at the University of Toronto working with Dr. Martin Krkošek, Dr. Marie-Josêe Fortin and Dr. Emily Darling on modelling coral reef networks to inform coral reef management design. I worked with Dr. Andrew Gonzalez at McGill during my BSc on modelling ecosystem functioning debts in metacommunities.

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Hidetoshi Inamine

Hidetoshi InamineI am a theoretical ecologist interested in how population processes at various scales generate and maintain biodiversity. Currently I am studying the effects of disturbance on the structure of ecological communities. Disturbances are ubiquitous in nature, and how different species in a community react ecologically and evolutionarily to disturbances affects the interactions between species and the overall community. I have a penchant for experiments, and collaborate with Angus Buckling at U Exeter (UK) to test theoretical predictions in bacterial microcosm. Before starting my postdoc at Penn State, I obtained my BA (Biological Sciences with specialization in Neuroscience) from U. Chicago, and my PhD (Ecology and Evolutionary Biology, Minor in Applied Mathematics) from Cornell with Steve Ellner.

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Jose Luis Herrera Diestra

JoseCurrently, I am a Research Associate affiliated to the UT Austin in the Lauren Meyers’ Lab, working with a joint project with the Department of Biology at PSU, actively collaborating with Matthew Ferrari and Katriona Shea. My research is focused on complex networks (dynamics on and of networks), disease spreading on networks and applications to surveillance, control and immunization of epidemic diseases. I obtained my PhD in Fundamental Physics from Universidad de Los Andes in Venezuela, where I worked as a professor for 10 years. I was a postdoctoral researcher and research scholar in the Meyers Lab in two previous occasions (2013 and 2015). I worked for two and a half years (2017 – 2019) as a postdoctoral researcher at ICTP – SAIFR, located in Sao Paulo – Brazil. At the moment, I am working on the characterization and analysis of the network of cattle exchanges in Turkey (aggregated and temporal) to propose potentially optimal surveillance strategies for the control of foot-and-mouth disease (FMD). In addition, I am developing computational and mathematical models to help us understand how different network features might affect the fate of diseases spreading in populations.

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Graduate Students

Emily Howerton


I am a Ph.D student in the Department of Biology studying the management of infectious diseases and invasive species. My research focuses on how we can combine biotic and abiotic forces, varying in space and time, to design more efficient and effective control strategies. For example, I study the interaction between diagnostic testing and non-pharmaceutical interventions in COVID-19 management, as well as the combined effects of pesticide application and native competition on fire ant invasion success. Further, my research includes the effects of scientific uncertainty on our ability to design such effective control strategies and explores how we might design robust control strategies in the face of this uncertainty.

Trevor Dress


I am an ecology PhD candidate in the Department of Biology and have a wide variety of interests at the intersection of ecology, statistics, and data science. My work primarily involves quantifying movement, namely plant dispersal, in ecological systems and seeking answers to questions regarding (a) modelling dispersal processes, (b) the probabilistic nature of dispersal, (c) relative contributions of multiple dispersal vectors in series and parallel, and (d) how current dispersal patterns may be affected by climate change. Dispersal and movement in ecological systems can be quite challenging to understand, and I use a variety of mechanistic and statistical models to help unravel the mysteries behind these processes. I am also interested in applications of machine learning to problems of classification and prediction, especially in the realms of science, engineering, medicine, and business.

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Emma van der Heide

ID PhotoI am a PhD student in the Ecology program with broad interests in disturbance ecology. More specifically, I study the impact of multiple disturbances on life history traits in invasive thistles, with specific focus on the types of disturbance that are likely to become more common as the climate changes. I’m also interested in exploring the similarities and differences in response to disturbance across study systems; this work will extend to cress and bacteria and include field, greenhouse, and lab work components. For a landscape-level perspective, I plan to look at how invasive thistles move across Pennsylvania, with emphasis on how land use and human-mediated disturbance allow an invasion to spread.

Katie Yan

IMG_5825I am a Ph.D. student in the Department of Biology studying the interplay between messaging and disease transmission. My research focuses on how we can use targeted messaging to illicit a response in the population that will affect disease transmission. Within my research I employ an interdisciplinary methodology combining empirical social science research with mathematical modeling to determine the optimal messaging time, type, and uptake in the general population. Through deepening our understanding on the impact of public health messaging I hope to inform decision makers on the optimal messaging strategy to help curb the spread of a disease.

Undergraduate Researchers

Elyse Johnson


I am a senior undergrad majoring in General Science with minors in Astrobiology and Wildlife/Fisheries Sciences. My empirical research studies the ramifications of early life stress timing and duration on plant life history traits.  Currently, I manage Shea Lab administration and oversee our research field in Rock Springs, PA. Beyond the lab, I am involved with the Nittany Artificial Intelligence Alliance, Happy Valley LaunchBox, and ACRES Project Nonprofit.

I joined the Shea lab in 2018 as a Women in STEM and Engineering Research (WISER) PA NASA Space Grant Intern studying how early life drought stress and resource competition interacts for microgreens (L. sativum). As a 2020 NSF REU, I simulated flash flooding and hail on thistle seedlings (C.acanthoides & C.nutans) to explore local extreme precipitation events as a source of uncertainty for agricultural management practices. I have also collaborated with Multi-Model for Outbreak Decision Support (MMODS) and designed affordable, home experiments for students K-12 to study early life stress using our microgreen system.  

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