Principal Investigator
Megan Frederickson
Professor
Ecology & Evolutionary Biology, University of Toronto
2009– Present
I study mutualism and symbiosis. ‘Symbiosis’ means two species live together, while ‘mutualism’ means two species benefit each other. Symbioses are often, but not always, mutualisms, and vice versa. Without mutualism and symbiosis, life on Earth would look radically different. Symbiotic microorganisms (the ‘microbiome’) affect the health, development, physiology, ecology, and evolution of most plants and animals, including humans. Mutualism and symbiosis also underpin many critical ecosystem functions, such as pollination, biological nitrogen fixation, and photosynthesis in coral reefs. My research aims to understand how mutualism and symbiosis have shaped the evolution of life on Earth, and how these interactions continue to affect biodiversity in the Anthropocene.
I began my career studying ant-plant symbiosis in tropical rainforests, but as my lab has grown, we’ve branched out to study a wide range of plant-animal and host-microbe mutualisms. Currently, I am developing a high-throughput experimental model of host-microbiome interactions using a tiny, fast-growing aquatic plant, duckweed (Lemna minor), and its microbes. I am also writing a book that synthesizes mutualism and microbiome research.
PREVIOUS APPOINTMENTS
Junior Fellow, Harvard Society of Fellows (2006-2009)
DEGREES
Ph.D. in Biological Sciences, Stanford University (2006)
A.B. magna cum laude with Highest Honors in Biology, Harvard University (2001)
Postdocs
Kevin Ricks
Postdoctoral Researcher
2023 – Present
I’m broadly interested in the evolutionary ecology of host-microbial symbioses, working towards identifying the evolutionary drivers and ecological impacts of host-symbiont coevolution. In the Frederickson Lab, I’m planning on investigating how host-microbe coevolutionary processes may impact higher order community dynamics and functions. Additionally, given the complex molecular environments in which these interactions persist, I also hope to integrate the molecular signaling and chemical ecology of the host-microbiome into the ecology and evolution of these systems. My approach to this area uses plants as a model system, and uses tools such as amplicon and whole genome sequencing, experimental evolution, and in vivo microbiome manipulation.
Takuji Usui
Postdoctoral Researcher
2023 – Present
I am an evolutionary ecologist investigating the eco-evolutionary processes that govern species geographical ranges and community assembly. I use a combination of experimental evolution, data synthesis, and field work to test how rapid feedbacks between population genetics and ecology scale up to influence macroecological patterns of biodiversity across space and over time. I am currently testing how coevolution between duckweed plants (Lemna minor, Spirodela polyrhiza, and Spirodela intermedia) and their microbial symbionts alters the dynamics of range expansion and patterns of species coexistence in nature.
Website: https://takujiusui.github.io/
Graduate Students
Julia Boyle
Ph.D. Candidate
2019 – Present
I am interested in the community assembly of plant microbiomes. In my thesis, I have explored how ecological timing, host genotype, and climate change alter the microbial community associated to a host plant, and the subsequent impacts on plant performance.
Pooja Nathan
Ph.D. Student
2019 – Present
Broadly, I am interested in the ecology and evolution of mutualistic interactions between plants and animals. I hope to shed light on the macroevolutionary impacts of mutualism and the network composition of plant-animal mutualisms involving more than one animal partner.
María C. Tocora
PH.D. Student
2020 – Present
Reciprocal selection in symbiotic systems is determined by different selective pressures among populations, and the environmental heterogeneity they are exposed to. I am investigating the genomics underlying reciprocal evolutionary change of host-symbiont interactions by exploring how the genetic structure of ants and their associated symbionts covary across space in the Galápagos Islands and continental South America.
Chris Carlson
Ph.D. Student
2021 – Present
I’m curious about the evolutionary genetics of
mutualistic coevolution. A few specific questions I’m interested in include:
Does coevolution between mutualists ever end? What forces, biotic and abiotic,
shape the coevolutionary process? What role (if any) do cheaters have in the
evolution of mutualism? Can mutualistic partners adapt to a rapidly changing
world? My research combines mathematical models from game theory and population
genetics, with manipulative laboratory experiments to address these and other
questions.
Jessie Wang
Ph.D. Student
2022 – Present
I am interested in the dynamics and stability of host-microbe interactions. How do these interactions vary across environmental gradients? How do microbial interactions scale up to affect a host? What determines the core microbiome, and to what extent can we predict the outcomes of host-microbe interactions? To answer these questions, I work with duckweed (genus Lemna), which are small, floating aquatic plants amenable to high throughput experimentation. Through my research, I aim to characterize species interactions across environments and the feedback between hosts and microbes.
Valmic Mukund
Ph.D. Student
2023 – Present
I am fascinated by the complex network of interactions that occur in biological communities across space and time. Through manipulative experiments, I seek to unweave this complex tapestry and better understand how interactions at one level of biological organization may impact interactions at another level. One specific topic I am interested in is the potential impact that bacteriophage viruses may have on legume-rhizobia interactions. Can the parasitism of phage on rhizobia disrupt the legume-rhizobia mutualism and decrease legume fitness? Does phage infection of rhizobia influence which rhizobia strains get incorporated into the nodules of legumes? To what extent do phages, as agents of horizontal gene transfer, actually increase the fitness of rhizobia (and potentially, the fitness of their legume hosts)? During my PhD, I hope to shed light onto the answers to these questions through greenhouse experiments, in vitro experiments, and sequencing.
Erin McHugh
Ph.D. Student
2023 – Present
Broadly, I am interested in the spatial ecology of plant-microbe interactions. How do plant microbiomes vary across species ranges and environmental gradients? What drives this variation, and is it adaptive for plant hosts? How will these microbiomes be altered under environmental change? I hope to provide some answers to these questions using greenhouse, field, and modelling approaches.
Lab Manager
Oxana Pogoutse
Lab Manager
2021 – Present
For many years I worked on projects which were mostly focused on yeast or bacteria proteomes and specific protein-protein interactions within a single cell of these organisms. Since joining the Frederickson Lab, I am excited to switch my research focus to studying interaction on a much larger scale: mutualistic interaction amongst a group of organisms. Currently, we investigate how the growth of a small aquatic plant, Lemna minor, commonly known as duckweed, is influenced by a combination of various biotic and abiotic factors.
Undergraduates
Yash Singhal
EEB397 Project Student
2022 – Present
My ultimate academic interests lie in understanding biological systems at both the micro and macro scales. I hope to not only advance our knowledge of the living world, but also help guide the development of innovative real-world applications. My current focus is on plant biology, particularly understanding the various adaptations through which plants interact with their abiotic environment and the other organisms around them. I am fascinated by how years of shared evolutionary histories can lead to the development of interesting physiological features in plants, facilitating unique relationships with non-plant species. I am also interested in exploring the immense diversity of strategies plants have evolved to survive in a wide range of biomes. At the Frederickson Lab, I am conducting a simulated herbivory study on the myrmecophyte Ricinus communis to further our understanding of their induced defence response.
Nishka Srivastava
Work-study Student
2022 – Present
My research interest is host-microbe mutualisms, using the model species L. minor (duckweed). I am currently investigating how varying inoculum bacterial concentration affects growth patterns of both duckweed and their associated microbes. I am also in a meta-analysis project investigating the fitness benefits conferred by microbial symbionts onto various animal hosts.
Lab Alumni
Past Graduate Students and Postdocs
- Tia Harrison, Ph.D., 2017-2023
- Jason Laurich, Ph.D. 2015-2023
- Anna O’Brien, Postdoc, 2017-2022
- Christopher Reid, M.Sc., 2018-2020
- Rebecca Batstone, Ph.D., 2012-2018 (top left)
- Mitch Trychta, M.Sc., 2016-2018
- Katrina Kaur, M.Sc., 2016-2018 (top middle)
- Shannon Meadley Dunphy, M.Sc., 2014-2016 (top right)
- Pierre-Jean Male, Postdoc, 2013-2016 (middle left)
- Emily Dutton, M.Sc., 2013-2015 (middle)
- Eric Youngerman, M.Sc., 2012-2014
- Adam Cembrowski, M.Sc., 2011-2013 (middle right)
- Kirsten Prior, Postdoc, 2011-2013 (bottom left)
- Kyle Turner, M.Sc., 2011 – 2013 (bottom middle)
- Lina M. Arcila Hernandez, M.Sc., 2010-2012 (bottom right)
Past Undergraduate Students
- Mila Gorchkova (EEB399 student, 2019-2020)
- Christopher Reid (EEB498 student, 2017-2018; NSERC USRA, summer 2018)
- Luxiang Wang (NSERC USRA, summer 2018; Centre for Global Change Science intern, summer 2016)
- Caroline Biel (EEB299 student, 2017-2018)
- Daniel Li (EEB399 student, 2017-2018)
- Nathaniel (Atticus) Murphy (EEB498 student, 2017-2018)
- Christopher Knox (EEB299 student, 2016-2017; Centre for Global Change Science intern, summer 2018)
- Emma Lash (Centre for Global Change Science intern, summer 2017)
- Judith Li (EEB399 student, summer 2017)
- Tianbi (Abby) Wu (EEB498 student (summer 2017)
- Xue Zhang (EEB399 student (2016-2017)
- Xin (Carol) Chen (EEB299 student, 2016-2017)
- Meghan Huskisson-Snider (NSERC USRA, fall 2016)
- Susan Gordon (NSERC USRA, summer 2015)
- Aadiyat Ahmad (EEB498 student, 2014-2015)
- Madeline Peters (EEB299 student, 2014-2015)
- Michael Liu (EEB299 student, 2014-2015)
- Simran Dhunna (Work-study, 2014-2015)
- Shannon Meadley Dunphy (EEB399 student, summer 2012; Work-study, 2012-2013; EEB 498 student, 2013-2014; NSERC USRA, summers 2013, 2014)
- Donglin Wang (Work-study, 2013-2015; Research assistant, summer 2014)
- Elaine Luo (EEB498 student, 2013-2014)
- Shreeram Senthivasan (EEB397 student, 2013-2014, work-study 2014-2015)
- Molly Yang (EEB299 student, 2013-2014)
- Neil Macalasdair (EEB299 student, 2013-2014)
- Lauren Moretto (EEB399 student, summer 2013)
- Gloria Cho (EEB399 student, summer 2013)
- Jackie Awad (EEB399 student, summer 2012; Work-study, 2012-2013)
- Margaret Thompson (Volunteer, 2012-2013; Work-study, 2011-2012)
- Kyle Gaynor (EEB498 student, 2012-2013)
- Harry Rusnock (EEB299 student, 2012-2013)
- Kriti Saxena (Volunteer, summer 2012; EEB299 student, 2012-2013)
- Jennifer Robinson (NSERC USRA, summer 2012)
- Viviana Astudillo (Work-study, 2010-2012) – check out her talent outside the lab: http://www.youtube.com/watch?
v=HQtDhj_MaHY&feature=youtu.be - Emily Dutton (NSERC USRA, summer 2011)
- Erinn Todd (EEB399 student, summer 2011)
- Reem Tawfik (Work-study, summer 2011)
- Ishita Aggarwal (Work-study, 2010-2011)
- Melissa Donnelly (Volunteer, 2010-2011)
- Annabelle Ong (Volunteer, 2010-2011)
- Kyle Turner (NSERC USRA and EEB499 student, 2010-2011)
- Greg Booth (EEB399 student, summer 2010)
- Alison Ravenscraft (Field assistant, 2009-2010)
PAST LAB MANAGERS and TECHNICIANS
- Emily Dutton (2015-2016)
- Adam Cembrowski (2013-2014)
- Jackie Day (2012-2013)
- Emma Hodgson (2011)
The Lab Through the Years
MAY 2023
From left: Rebecca Batstone, Sangay Bhutia, Anna O’Brien, Tia Harrison, Megan Frederickson, Jason Laurich.
Fall 2019
From left: Megan Frederickson, Mila Gorchkova, Tia Harrison, Julia Boyle, Jason Laurich, Christopher Reid, Pooja Nathan.
Spring 2017
From left: Anna O’Brien, Rebecca Batstone, Jason Laurich, Megan Frederickson, Shannon Meadley Dunphy, Katrina Kaur, Mitch Trychta.
Summer 2014
From left: Pierre-Jean Malé, Shannon Meadley Dunphy, Megan Frederickson, Emily Dutton, Adam Cembrowski, Rebecca Batstone, Donglin Wang.
Fall 2012
From left, top row: Jackie Day, Eddie Ho, Rebecca Batstone, Margaret Thompson, Kirsten Prior. Middle row: Kyle Gaynor, Eric Youngerman, Adam Cembrowski, Shannon Meadley Dunphy, Kriti Saxena. Front row: Harry Rusnock, Lina Arcila Hernandez, Megan Frederickson.
Spring 2011
From left: Emma Hodgson, Melissa Donnelly, Ishita Aggarwal, Lina Arcila Hernandez, Kyle Turner, Megan Frederickson, Kirsten Prior, Annabelle Ong, Antonio Coral.