Ecology &amp; Evolutionary Biology

Emerging and Pandemic Infections Consortium

Institutional Strategic Initiatives

Graduate Students

Subheadline

PhD student Youngseo Jeong is using a mathematical model to explore the effect of vaccination on the parasite that causes malaria

A University of Toronto PhD student is shedding light on a poorly understood phenomenon that could impact vaccination strategies for malaria and other infectious diseases.

The phenomenon, called vaccine-driven evolution, describes possible scenarios where immunization could drive a pathogen to become better at causing disease – for example, by evading the immune system.

Youngseo Jeong (supplied image)

“I’m interested in how interventions like vaccines shape the evolution of virulence and other related parasite traits,” says Youngseo Jeong, a PhD student in the Faculty of Arts & Science’s department of ecology and evolutionary biology.

Specifically, she is focused on the Plasmodium family of parasites that are commonly transmitted by mosquitoes and that can cause the life-threatening disease malaria in humans.

The World Health Organization estimates that there were 249 million malaria cases globally in 2022 and 608,000 malaria deaths, with the African region bearing the heaviest burden. With the approval of the world’s first malaria vaccine in 2021and a second vaccine in 2023, vaccination programs have become an important part of the public health strategy to combat the disease.

However, the launch of malaria vaccination campaigns in the African region comes at a time when progress against the disease has stalled and two of the most important tools to prevent and treat malaria are losing their effectiveness. Insecticide-treated bed nets, a mainstay to prevent mosquito bites and kill mosquitoes, offer less protection as mosquitoes become increasingly resistant to the insecticides. Similarly, clinicians are concerned that the spread of Plasmodium parasites resistant to frontline antimalarial drugs will hamper their ability to treat the disease.

Both of these challenges arose as a result of mosquito and parasite evolution in response to a human intervention. Whether a malaria vaccination program could lead to similar changes in the Plasmodium parasite is a key question in the field and one that Jeong aims to answer through her work with Nicole Mideo, an associate professor of ecology and evolutionary biology.

With the support of a doctoral award from the Emerging and Pandemic Infections Consortium, a �Թϱ�� institutional strategic initiative, she is applying mathematical approaches to study how parasites evolve in hosts who have been vaccinated versus hosts who have not.

Jeong’s research, based on a mouse model of malaria, builds on a 2012 study from American researchers that found Plasmodium parasites caused more severe disease after repeated infections of vaccinated mice. However, the researchers did not find any changes to the part of the parasite targeted by the vaccine – a common process by which pathogens evade vaccine-induced immunity – and the cause of the parasite’s increased virulence remains unknown.

To identify the specific traits that are responsible for the parasite’s enhanced abilities, Jeong is using a mathematical model of malaria infection fitted with data from the 2012 study. She will determine which parameters, or parasite traits, in her model can explain the differences between parasites that evolved in vaccinated and unvaccinated hosts.

In the second phase of her PhD project, Jeong will refine the model by including relevant biological processes such as vaccine-induced immunity and the specific parasite characteristics she identified earlier. She will also create a new mathematical model to simulate evolution in a vaccinated host and validate her earlier findings.

“I want to highlight not just evolution at the vaccine target sites, which receives more attention generally, but I also want to draw attention to other pathogen traits and their interactions with host processes that could have consequences for how effective the vaccines are,” says Jeong.

She hopes that her work will contribute to a better understanding of how vaccine-driven evolution in parasites can lead to more severe infection outcomes in both vaccinated and unvaccinated individuals, and underscore the importance of considering this phenomenon when designing new malaria vaccines and immunization programs.

Scientists develop framework to measure plastic emissions

Christopher.Sorensen — Mon, 22 Apr 2024 19:43:38 +0000

Scientists develop framework to measure plastic emissions

Christopher.Sorensen Mon, 04/22/2024 - 15:43

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(photo by Alastair Berg via Getty Images)

Sean Bettam

Topic

Sunnybrook Health Sciences Centre

Graduate Students

Sustainability

�Թϱ�� Scarborough

Subheadline

Model developed by researchers at �Թϱ�� and the Rochester Institute of Technology suggests that Toronto emitted nearly 4,000 tonnes of plastic pollution in one year alone

Researchers at the University of Toronto have developed a framework for measuring plastic pollution emissions – not unlike the global standard for measuring greenhouse gas emissions.

They say the approach will boost identification of the biggest contributors to plastic pollution from local to national levels and improve strategies in reducing emissions worldwide.

Using Toronto as a model, the first-of-its-kind framework suggests that, in one year alone, Canada’s largest city emitted nearly 4,000 tonnes of plastic pollution.

Alice (Xia) Zhu (supplied image)

“That’s roughly 400 garbage trucks’ worth of plastic that leaks into the environment annually from across the city,” said Alice (Xia) Zhu, lead author of a study outlining the method published in Environmental Science & Technology.

“Assigning responsibility for the pollution to a jurisdiction with the ability to enact laws means there is no hiding where the pollution came from. It presents an opportunity to identify major sources of plastic pollution within the area and inform measures to curb these emissions.”

A PhD candidate in the department of physical and environmental sciences at �Թϱ�� Scarborough who is working with Assistant Professor Chelsea Rochman in �Թϱ��’s department of ecology and evolutionary biology in the Faculty of Arts & Science, Zhu developed the framework with colleagues at �Թϱ�� and the Rochester Institute of Technology. The researchers took inspiration from guidelines for compiling emissions inventories of greenhouse gases established by the United Nations’ Intergovernmental Panel on Climate Change. Adapting for physical differences between greenhouse gases and solid pieces of plastic, the researchers used a similar methodology of identifying the major pollution-generating activities in a particular area, calculating the amount of pollution generated by each activity within a given period and accounting for uncertainties associated with each source of pollution-generating activity.

The framework arrives ahead of international discussions in Ottawa, from April 23 to 29, towards a legally binding global agreement on plastic pollution. The discussions are being led by the UN’s Intergovernmental Negotiating Committee on Plastic Pollution.

Plastic pellets collect around a storm drain near an industrial plant (photo courtesy of �Թϱ�� Trash Team)

“Our goal was to develop an accounting mechanism or tool for measuring plastic emissions that any level of government can adopt,” said Zhu. “But most importantly, we hope this tool we have introduced will allow the plastic field to follow in the footsteps of the climate field, where countries submit national emissions inventories to an international body such as the United Nations to track our progress towards reaching a globally defined target.”

Currently, national emissions inventories of plastic pollution do not exist, nor does a globally defined target for reducing plastic pollution.

Waste from littering, including fragments of foam packaging, accounted for the greatest share of an estimate of plastic pollution in Toronto in 2020 (photo courtesy of �Թϱ�� Trash Team)

To demonstrate the utility of the framework, the researchers built an emissions inventory of plastic pollution for the City of Toronto for the year 2020 that draws from publicly available data gathered through municipal litter audits and other sources. From a list of nine types of sources – including littering, tire dust from airplanes and on-road vehicles, washing machines and paint from road markings and the exteriors of houses – they estimated between 3,531 and 3,852 tonnes of plastic pollution were emitted from within the city’s boundaries during the period.

Littering made up the largest share of the total at 3,099 tonnes, while artificial turf was responsible for the most emissions of microplastics – particles less than five millimetres in diameter – at 237 tonnes.

“It is not surprising that larger materials – known as macroplastics, and in this case from mismanaged waste such as littering – made up the majority of the mass. But it overshadows the small stuff: microplastics,” said Rochman, a co-author of the study and Zhu’s PhD supervisor. “Microplastics tend to be the highest by count in terms of actual pieces. This suggests that policies relevant to microplastics, in addition to macroplastics, are critical to reduce plastic emissions in the City of Toronto.”

Paint peeling from buildings and road markings are significant sources of microplastic pollution (photo courtesy of �Թϱ�� Trash Team)

The researchers selected Toronto to test the framework since it is the largest city in Canada and the fourth-largest city in North America.

“It’s an urban hub for various activities – and where you have lots of people and activity, you inevitably generate a lot of pollution,” said Zhu. “For a successful and informative case study, you want to look at a place with a lot of different sources of pollution. By doing so, you can identify which sources should be prioritized for the reduction of pollution out of all the others, and thereby demonstrate the utility of an emissions inventory for informing local policy.”

Zhu said emissions inventories of plastic pollution must be a foundational piece of a successful global treaty on plastic, and that the framework should be applied to other cities, provinces and states, and countries around the world to better understand what kinds of plastic pollution are being released into the environment.

“The guidelines can be applied to regions worldwide, regardless of what kinds of sources are there,” Zhu said. “Each geographic region will have different characteristics and the inventory will allow for the development of solutions tailored to that specific region.”

From building bone to children’s literacy: 36 �Թϱ�� researchers awarded Canada Research Chairs

lanthierj — Tue, 29 Aug 2023 17:51:06 +0000

From building bone to children’s literacy: 36 �Թϱ�� researchers awarded Canada Research Chairs

lanthierj Tue, 08/29/2023 - 13:51

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Karina Carneiro, an assistant professor in the Faculty of Dentistry, is one of 36 researchers at �Թϱ�� and its partner hospitals to receive a new or renewed Canada research chair (photo by Jeff Comber)

Topic

Temerty Faculty of Medicine

Canada Research Chairs

Centre for Addiction and Mental Health

Computer Science

Dalla Lana School of Public Health

Faculty of Applied Science & Engineering

Economics

Hospital for Sick Children

Faculty of Dentistry

Geography and Planning

Leslie Dan Faculty of Pharmacy

Ontario Institute for Studies in Education

University Health Network

�Թϱ�� Scarborough

Subheadline

The new and renewed chairs at �Թϱ�� and its hospital partners were part of a broader research funding announcement by the federal government

At the University of Toronto’s Faculty of Dentistry, Karina Carneiro and her team are working on developing new treatments to regenerate bone with DNA-based biomaterials.

Karina Carneiro (photo by Jeff Comber)

The researchers are exploring ways to use synthetic materials, created using DNA nanotechnology, to help bones regenerate and support the body’s efforts to heal them naturally.

That’s in contrast to current bone repair treatments, which involve taking bone tissue from another part of the body and breaking it into little pieces that can be inserted into the defect.

“Using a DNA-gel for this purpose could be an effective treatment option as it can be injected to fill the defect size fully,” says Carneiro, an assistant professor in the faculty.

“What we believe to be the difference between our DNA gel and other materials being developed is that over time, the DNA can degrade into molecules that promote our own body’s healing mechanism to further regenerate the bone.”

Carneiro is one of three researchers at the Faculty of Dentistry to be awarded a new or renewed Canada Research Chair in the latest round – and one of 36 across �Թϱ��’s three campuses and hospital partners (see list below).

Established in 2000, the prestigious federal program aims to recruit and retain top researchers and scholars in the country. It invests more than $300 million annually to enable world-class researchers to reach new heights in disciplines spanning engineering, health sciences, humanities and social sciences.

“Congratulations to all the researchers at the University of Toronto who received new or renewed Canada Research Chairs in the latest round,” says Leah Cowen, �Թϱ��’s vice-president, research and innovation, and strategic initiatives.

“From using AI to improve medicine and health care to better understanding Indigenous geographies and environmental dispossession, the work by �Թϱ�� investigators supported by this important federal program is pushing the boundaries of research and innovation – and promises to have a big impact in Canada and around the world.”

Anil Kishen (photo by Jeff Comber)

Professor Anil Kishen, who is also at the Faculty of Dentistry, will use the funding associated with his Tier 1 Canada Research to advance his work in oral health nanomedicine.

He and his colleagues in the Kishen Lab are using multifunctional bioactive nanoparticles to study how cells communicate with each other and how wounds heal – in particular, how nanoparticles can be used to help save infected natural teeth and treat wounds and ulcers in individuals with diabetes.

Kishen says one of the reasons chitosan-based nanoparticles, which are optimized for different therapeutic applications, are so promising is because they’re derived from a naturally occurring molecule that is readily available.

“Affordability is important when developing a treatment to reach the masses,” Kishen says.

Massieh Moayedi (photo by Jeff Comber)

Massieh Moayedi, an associate professor in the Faculty of Dentistry, is receiving funding to pursue research in pain neuroimaging as a Tier 2 Canada Research Chair.

“There’s tenuous evidence that body image might be involved in some types of chronic pain,” Moayedi says, adding that his end goal is to understand how pain works so he can improve patient outcomes.

He’s already shown that people with arthritic hands who see the limb looking healthier through a special device experience improvements in pain, so he’s now trying to understand which brain regions are involved.

“This chair will give me funding and the capacity to allow me to investigate these questions, and to really understand the relationship between pain and body image.”

Randy Boissonnault, minister of employment, workforce development and official languages, announced the CRCs at a press conference on Aug. 29 on behalf of François-Philippe Champagne, minister of innovation, science and industry, and Mark Holland, minister of health.

He also revealed the researchers and projects receiving funding through a diverse array of programs administered by the Natural Sciences and Engineering Research Council of Canada (NSERC), the Social Sciences and Humanities Research Council (SSHRC) and the Canadian Foundation for Innovation (CFI).

They include the recipients of the SSHRC’s Partnership Grants, Partnership Development Grants and Insight Grants, as well as the recipients of the CFI’s John R. Evans Leaders Fund (JELF), which helps institutions to recruit and retain outstanding researchers, and provide them with the necessary tools and technology to perform their work. Named after a former �Թϱ�� president, JELF supports projects that deal with a range of pressing issues. This year’s recipients include 35 researchers at �Թϱ�� and its hospital partners sharing a total of more than $11 million for projects ranging from an assessment of plant responses to environmental change to the development of an ultra-sensitive cryogenic detector for dark matter and neutrino experiments.

“The federal government’s ongoing support for research through all of these programs – from the John R. Evans Leaders Fund, to the NSERC and CFI grants and the Canada Research Chairs – is critical to supporting the kind of research that ultimately improves lives through new knowledge and innovations,” Cowen said.

Here is the full list of new and renewed Canada Research Chairs at �Թϱ��:

New Canada Research Chairs

Stephanie Ameis at the Centre for Addiction and Mental Health and in the department of psychiatry in the Temerty Faculty of Medicine, Tier 2 in neuroimaging of autism and mental health in youth
Yvonne Bombard at Unity Health and in the Institute of Health Policy, Management and Evaluation in the Dalla Lana School of Public Health, Tier 2 in genomics health services and policy
Karina Carneiro in the Faculty of Dentistry, Tier 2 in DNA-based biomaterials
Jesse Chao at the Sunnybrook Health Sciences Centre and in the department of medical biophysics in the Temerty Faculty of Medicine, Tier 2 in precision cancer diagnostics and artificial intelligence
Xi (Becky) Chen-Bumgardner in the department of applied psychology and human development in the Ontario Institute for Studies in Education, Tier 1 in literacy development of bilingual and multilingual children
Mark Chiew at the Sunnybrook Health Sciences Centre and in the department of medical biophysics in the Temerty Faculty of Medicine, Tier 2 in computational biomedical imaging
Sarah Crome at University Health Network and in the department of immunology in the Temerty Faculty of Medicine, Tier 2 in tissue-specific immune tolerance
Michelle Daigle in the department of geography and planning in the Faculty of Arts & Science, Tier 2 in Indigenous geographies and environmental dispossession
Karen Davis at University Health Network and in the department of surgery in the Temerty Faculty of Medicine, Tier 1 in acute and chronic pain research
Rahul Gopalkrishnan in the department of computer science in the Faculty of Arts & Science and department of laboratory medicine and pathobiology in the Temerty Faculty of Medicine, Tier 2 in computational medicine
Housheng (Hansen) He at University Health Network and in the department of medical biophysics in the Temerty Faculty of Medicine, Tier 1 in RNA medicine
Margaret Herridge at University Health Network and in the department of medicine in the Temerty Faculty of Medicine, Tier 1 in critical illness outcomes and the recovery continuum
Anil Kishen in the Faculty of Dentistry, Tier 1 in oral health nanomedicine
Bowen Li in the Leslie Dan Faculty of Pharmacy, Tier 2 in RNA vaccines and therapeutics
Iacovos Michael at Sunnybrook Health Sciences Centre and in the department of medical biophysics in the Temerty Faculty of Medicine, Tier 2 in tumor biology and precision oncology
Massieh Moayedi in the Faculty of Dentistry, Tier 2 in pain neuroimaging
Faiyaz Notta at the University Health Network and in the department of medical biophysics in the Temerty Faculty of Medicine, Tier 2 in pancreatic cancer and cancer evolution
Valeria Rac at the University Health Network and in the Institute of Health Policy, Management and Evaluation in the Dalla Lana School of Public Health, Tier 2 in health system and technology evaluation
Fahad Razak at Unity Health Toronto and in the department of medicine in the Temerty Faculty of Medicine, Tier 2 in health-care data and analytics
Clinton Robbins at the University Health Network and in the department of laboratory medicine and pathobiology in the Temerty Faculty of Medicine, Tier 1 in cardiovascular immunology
Lena Serghides at the University Health Network and in the department of immunology in the Temerty Faculty of Medicine, Tier 1 in maternal-child health and HIV
Catriona Steele at the University Health Network and in the department of speech language pathology in the Temerty Faculty of Medicine, Tier 1 in swallowing and food oral processing
Bo Wang in the department of computer science in the Faculty of Arts & Science and department of laboratory medicine and pathobiology in the Temerty Faculty of Medicine, tier 2 in artificial intelligence for medicine

Renewed Canada Research Chairs

Angela Cheung at University Health Network and in the department of medicine at the Temerty Faculty of Medicine, Tier 1 in musculoskeletal and postmenopausal health
Xi Huang at the Hospital for Sick Children and in the department of molecular genetics in the Temerty Faculty of Medicine, Tier 2 in cancer biophysics
Cendri Hutcherson in the department of psychology at the University of Toronto Scarborough, Tier 2 in decision neuroscience
Joanne Kotsopoulos at Women’s College Hospital and at the Dalla Lana School of Public Health, Tier 2 in hereditary breast and ovarian cancer prevention
Arthur Mortha in the department of immunology in the Temerty Faculty of Medicine, Tier 2 in mucosal immunology
Kelly O’Brien in the department of physical therapy in the Temerty Faculty of Medicine, Tier 2 in episodic disability and rehabilitation
Trevor Pugh at the University Health Network and in the department of medical biophysics in the Temerty Faculty of Medicine, Tier 2 in translational genomics
Diego Restuccia in the department of economics in the Faculty of Arts & Science, Tier 1 in macroeconomics and productivity
David Sinton in the department of mechanical and industrial engineering in the Faculty of Applied Science & Engineering, Tier 1 in energy and fluids
Olivier Trescases in the Edward S. Rogers Sr. department of electrical and computer engineering in the Faculty of Applied Science & Engineering, Tier 2 in power electronic converters
Joel Watts in the Tanz Centre for Research in Neurodegenerative Diseases in the Temerty Faculty of Medicine, Tier 2 in protein misfolding disorders
Michael Widener in the department of geography and planning in the Faculty of Arts & Science, Tier 2 in transportation and health
Stephen Wright in the department of ecology and evolutionary biology in the Faculty of Arts & Science, Tier 1 in population genomics

By studying lizards, researchers reveal the forces that shape biodiversity

Christopher.Sorensen — Mon, 20 Mar 2023 14:49:55 +0000

By studying lizards, researchers reveal the forces that shape biodiversity

Christopher.Sorensen Mon, 03/20/2023 - 10:49

Cutline

Researchers in �Թϱ��’s department of ecology and evolutionary biology studied anoles on the islands of Jamaica and Hispaniola to better understand what determines biodiversity (all photos courtesy of Luke Mahler)

Chris Sasaki

Topic

Graduate Students

“If you pick a spot in, say, a rainforest, and count the number of different species of lizards within 15 metres and you come up with a number,” says Luke Mahler, “What determines that number?”

Mahler is an assistant professor in the University of Toronto’s department of ecology and evolutionary biology in the Faculty of Arts & Science. He studies how the interplay of ecological and evolutionary forces over time and space results in the biodiversity we see in different habitats. He does this primarily by studying Anolis lizards – aka anoles – small, tree-dwelling reptiles in tropical regions of the Americas.

What determines the number of different species in local communities of animals? The question is a long-standing ecological problem for which there has been no consensus.

“Is it because of local processes like competition for food or territory?” Mahler asks. “Or is it the result of broader, regional processes like the generation of new species by evolution?”

One hypothesis suggests the determining force is local competition. In other words, if a local community – for example, a particular patch of forest on a tropical island – is “full up” with several species, then additional species wouldn’t be able to persist because every ecological niche is already occupied.

Anole lizards are small, tree-dwelling reptiles.

But according to another hypothesis, the diversity of species in such an area isn’t limited by a pre-existing number of niches. Instead, the most important factor determining the number of species in a local community is the diversity of the broader region.

“On an island with a small total number of species, local communities should have only a small number of species,” Mahler explains. “But on an island that has many species, you should see many species in local communities. In other words, local diversity is essentially a reflection of broader diversity, with classic ecological processes like competition mattering very little.

“If regional diversity determines what you see at a local site, then that local diversity is ultimately determined by the large-scale evolutionary processes that created the regional diversity.”

To answer the question of local versus regional, Mahler and his colleagues studied anoles on the Caribbean islands of Jamaica and Hispaniola. What the researchers found was evidence for an unexpected third option – one that required marrying elements of both the “local” and “regional” hypotheses.

They found that the diversity of species in local communities indeed seems to be determined by local ecological processes that cap species diversity – but only if regional evolutionary forces have already produced the kinds of species that can monopolize local ecological resources. For example, the rich evolutionary diversity of species on Hispaniola, a large and ancient island, has “fed” a wealth of specialized species into the local communities at higher elevations on that island.

Luke Mahler (far right) and Luke Frishkoff (fourth from left) pose for photo with students.

Why? Hispaniola’s diversity – which stems from evolution playing out over millions of years across a very large and complex area – has led to unique anole species that exist only in the highlands. These species have filled all the available ecological niches, precluding more species from joining local communities there.

In contrast, Jamaica is smaller in area, especially in the highlands. And while many anole species have evolved on the island, the relative lack of space in the highlands hasn’t allowed the evolution of new highland-specialist species as it has on Hispaniola. In fact, there is only one distinct highland anole in Jamaica.

Put another way: local diversity is determined by both regional and local forces but in different ways. Regional forces produce a diverse set of species, which then compete with one another, establishing local limits on diversity in any given location. But if a region is lacking in “evolutionary opportunity” because it’s too small or too young, it fails to produce a diverse assembly of species and local limits are never reached.

Mahler and his colleagues described these findings in their study, published recently in the journal Ecology Letters. Co-authors included Luke Frishkoff, who started working on the research as a post-doctoral researcher in Mahler’s lab and who is now an assistant professor at the University of Texas at Arlington, and Gavia Lertzman-Lepofsky, a PhD candidate currently in Mahler’s lab.

The “laboratories” in which Mahler and his colleagues conducted their research – Jamaica and Hispaniola – were chosen because they are similar in many ways. They are situated at the same latitude, have matching topography and have similar forest habitats.

Every summer from 2016 to 2018, the researchers counted the number of anole species in dozens of 30-metre diameter plots on both islands from sea level to an altitude of approximately 2,000 metres.

“The anole faunas of Jamaica and Hispaniola provide a rich opportunity for comparison because they represent a natural experiment,” Mahler says. “And what we found is that local processes do matter. But they matter in such a way that it's regional opportunities for diversification that determine their strength.”

“However, this is a single, if illustrative, comparison. Determining the generality of the evolutionary opportunity model we propose here awaits additional tests.”

'I want to make room for people': Pilot program aims to level the playing field in field research

Christopher.Sorensen — Wed, 23 Nov 2022 14:12:05 +0000

'I want to make room for people': Pilot program aims to level the playing field in field research

Christopher.Sorensen Wed, 11/23/2022 - 09:12

Cutline

Mariel Terebiznik, a �Թϱ�� alumna and founder of the FREED program, holds a juvenile snapping turtle in the field (photo by Jasmine Veitch)

David Goldberg

Topic

Trinity College

Woodsworth College

Field research experience is key to success for many University of Toronto students, and now the Field Research in Ecology and Evolution Diversified (FREED) program is helping those who identify as Black, Indigenous or people of colour have equal opportunities to thrive.

“Field work is extremely expensive, which closes the doors for so many people due to systemic factors or financial issues,” says Mariel Terebiznik, who recently graduated from �Թϱ�� with a master’s degree in ecology and evolutionary biology and co-founded FREED alongside Aranya Iyer, a graduate student at Western University.

“I want to make room for people who don't have access to these spaces.”

A group of students on a hike as they conduct field research in Algonquin Park as part of the FREED program (photo by Jasmin Jeong)

In association with the department of ecology and evolutionary biology (EEB) in the Faculty of Arts & Science, FREED completed a successful pilot program this past summer. It involved a week of education, travel and accommodation at the Algonquin Wildlife Research Station, immersing student in paid and intensive field work environments where they gain crucial experience for future research positions.

Njal Rollinson, an assistant professor in the department of ecology and evolutionary biology, acted as faculty sponsor. He says he understands how crucial such programs are for students’ success.

“It’s important to get this type of research experience under their belt so they can put it on their resume,” says Rollinson. “And it helps them clarify whether they want to go into field research in the first place.

“These are the fundamentally important things that most people like me had the privilege of experiencing early on in my career whereas others haven’t.”

This year, the program included students from �Թϱ�� and Western, with donations from the �Թϱ�� community, including alumni, going directly toward �Թϱ�� students.

"We don't always have the support system to go into research or academia and it really meant a lot to have this kind of community,” says Jasmin Jeong, who attended FREED as a life sciences student in her second year with Woodsworth College.

“It's comforting to know there are other people out there who want to do things that I want to do.”

From canoeing and catching turtles to humanely trapping flying squirrels, as well as tree and insect identification, the students learned valuable skills about scientific research while they cultivated a network of peers and mentors.

“We talked about our experiences as racialized students and how it might have been harder for some of us, but talking about the intersectionality of our identities was really comforting,” says FREED participant Angela Wang, a fourth-year life sciences student with Trinity College.

“It was the best summer experience of my undergraduate career. Even though it was a lot of hard work, it didn’t feel like work.”

Thanks to sponsorship from academic partners including �Թϱ�� and Ontario Parks, the students had access to camping and research equipment, outdoor living and safety training, a hike along Algonquin's scenic Beaver Pond Trail off the Highway 60 corridor and a guided wolf howl by the midnight moonlight.

"It can be a little scary but don’t be afraid to try new things and talk to different people,” says Jeong, who advises future FREED participants to go outside their comfort zone if they want to get the most out of the experience.

The sun rises at the Algonquin Wildlife Research Station, where students participated in the first ever FREED program (photo by Angela Wang)

The week-long program offers students an invaluable opportunity that might otherwise be inaccessible.

“It's such a great opportunity to discover something you might be passionate about,” says Wang, who adds she will always cherish the friendships she forged during her week in the wilderness.

“We even joked about having a 25-year reunion, and I think someone will make that happen.”

FREED plans to run again in summer 2023 and organizers are already looking at expansion, with the possibility of adding more groups of students over multiple weeks.

“This was such an incredible success and I can’t wait to see what the future brings,” says Rollinson, who envisions different FREED chapters across Ontario in the years to come.

"Starting this program was one of the most fulfilling experiences of my life,” says Terebiznik. “We were blown away by the support and we were never turned down by the people we looked to for help.”

Fossil algae, dating from 541 million years ago, offer new insights into the plant kingdom's roots

Christopher.Sorensen — Thu, 22 Sep 2022 17:15:53 +0000

Fossil algae, dating from 541 million years ago, offer new insights into the plant kingdom's roots

Christopher.Sorensen Thu, 09/22/2022 - 13:15

Cutline

At left, the external surface of Protocodium sinense. Middle, the view through the outer layer made up of utricles. At right, the central siphons (photo by Cédric Aria)

Josslyn Johnstone

Topic

Global

Paleontologists have identified a new genus and species of algae called Protocodium sinense that predates the origin of land plants and modern animals and provides new insight into the early diversification of the plant kingdom.

Discovered at a site in China, the 541-million-year-old fossil is the first and oldest green alga from this era to be preserved in three dimensions, enabling the researchers to investigate its internal structure and identify the new specimen with unprecedented accuracy.

The study was published this week in BMC Biology, opening a window into a world of evolutionary puzzles that scientists are just beginning to unravel.

Reconstruction of a cross-section through Protocodium sinense, showing likeness to modern Codium (illustration by Shu Chai)

“Protocodium belongs to a known lineage of green algae and has a surprisingly modern architecture, showing that these algae were already well diversified before the end of the Ediacaran period,” says co-author Cédric Aria, a post-doctoral researcher in the University of Toronto’s department of ecology and evolutionary biology in the Faculty of Arts & Science who is based at the Royal Ontario Museum (ROM).

“Its discovery touches the origin of the entire plant kingdom and puts a familiar name on the organisms that preceded the Cambrian explosion over half a billion years ago, when the world’s first modern ecosystems emerged.”

The newly discovered Protocodium fossils were found by a team led by Hong Hua, a geology professor, and post-doctoral researcher Shu Chai – both of Northwest University in Xi’an, China. It is part of the Gaojiashan biota, the name given to a significant group of exceptionally well-preserved fossils, at the Dengying Formation in Shaanxi Province. In the past 20 years, this geological formation has yielded important fossil species documenting the end of the Ediacaran Period 541-million-years ago.

Simplified phylogeny or tree of life showing the relation of Protocodium and other green algae, known as chlorophytes, to other major lineages of plants (illustration by Cédric Aria)

Organisms and their parts that do not originally absorb minerals – unlike shells or bones – require exceptional conditions to be preserved. In this case, the whole fossils and their fine cellular details were preserved in three dimensions due to the replacement of the original organic material by phosphate. This mode of preservation allowed the researchers to use various electron and X-ray microscopy techniques to virtually slice the fossil, unveil its internal structure with precision and ultimately identify it as a close relative of the modern Codium alga, a type of seaweed.

Protocodium fossils are small spheres half a millimetre wide, about the size of large grains of pollen, covered by a multitude of smaller domes. Thanks to the 3D examination, the researchers determined the domed surface to be part of a complex, single cell that contains thin strands called siphons. This morphology is typical of certain modern single-celled seaweeds that contain many nuclei.

The discovery of Protocodium would call for caution when identifying generic spherical Ediacaran fossils and may imply that organisms like Codium are in fact much older and widespread. The famous Doushantuo fossil embryos, also from China and preserved in 3D, have been at the heart of debates about the deep origin of certain animal groups. Specific stages of some of these animal-like embryos resemble the unicellular Protocodium on the outside, but 3D slicing reveals how they are composed of many cells. On the other hand, numerous 2D, round fossils of uncertain algal or other affinity are also known from the Ediacaran and older periods, but in less detail.

“We know that seaweed-like fossils are at least one billion-years-old,” says Chai, the study’s first author. “But until now, flat, grainy two-dimensional preservation has made it challenging to recognize more than general morphological structures.”

Images of Protocodium sinense using electron microscopy (A) and X-ray computed tomography (B-D). Panels B-D reveal the internal structure (image by Shu Chai, Cédric Aria and Hong Hua)

Green algae are photosynthetic organisms, which means they convert light and carbon dioxide into sugars and oxygen. They were therefore likely important foundations of Earth’s early ecosystems, and the study suggests green algae were already established in the world’s shallow waters as CO2 recyclers and oxygen producers before the Cambrian explosion.

Apart from its smaller size, Protocodium appears surprisingly identical to the modern Codium, a type of green algae found in many seas worldwide. Certain types of this seaweed are notoriously invasive – such as Codium fragile subspecies tomentosoides, dubbed “dead man’s fingers” for its appearance and spread along with commercially farmed shellfish. From an evolutionary perspective, green algae like the ancient Protocodium and land plants share a common ancestor that was thought to be about one billion to one billion and a half years old – but is now likely older since the assignment of Protocodium so close to a modern group pushes back in time the history of the entire plant kingdom.

“It’s very telling that such an organism has remained practically unchanged over at least 540 million years,” says Aria. “By the Ediacaran, evolution had driven it towards a stable adaptive zone – it’s been comfortable there since and, more than that, quite successful – so much so, in fact, that nowadays Codium takes advantage of global trade to easily outcompete other algal species.”

Funding support for the research and field work came from the National Natural Science Foundation of China and the National Key Research and Development Program. Aria’s post-doctoral fellowship is funded via the Polk Milstein Family Trust Fund (ROM) and the Natural Sciences and Engineering Research Council of Canada

From eSports to K-pop, �Թϱ�� hosts hundreds of community-oriented clubs and student groups

Christopher.Sorensen — Thu, 25 Aug 2022 19:16:05 +0000

From eSports to K-pop, �Թϱ�� hosts hundreds of community-oriented clubs and student groups

Christopher.Sorensen Thu, 08/25/2022 - 15:16

Cutline

Members of UTSC Cheer run through a routine at Beach Cheer Athletics in Scarborough. The club is open to all �Թϱ�� students, regardless of athletic ability (photo by Geoffrey Vendeville)

Geoffrey Vendeville

Topic

UTogether

Cell and Systems Biology

Arts & Science news staff

Undergraduate Students

For many students, clubs are key part of the University of Toronto experience – helping them to meet like-minded people, form lasting friendships and learn outside class.

And there are literally hundreds of extracurricular options across �Թϱ��’s three campuses.

The Student Organization Portal – a clubs directory – is a one-stop shop for information on recognized campus groups, ranging from “architecture” to “zero waste.” The portal includes information on what each group does and how to go about joining.

Here is just small selection of �Թϱ��’s student clubs and other groups:

UTM eSports

The UTM eSports club brings students together to play video games such as Valorant, League of Legends and Super Smash Bros. (photo courtesy UTM eSports)

Last year, about three billion people – more than a third of humanity – were active video gamers, according to Statista, a German market and consumer data company. Within the next two years, that number is expected to grow to 3.32 billion.

While gaming has come a very long way since physicist William Higinbotham invented what’s said to be the first video game, Tennis for Two, in 1958, people are still getting used to the idea of professional gaming competitions, says Peter Ghobrial, president of the UTM eSports club and a computer science major.

“Video games in general are mainstream but the act of competing in them is on its way there,” he says.

At �Թϱ�� Mississauga, the club provides a friendly space in the Student Centre for gamers to socialize and compete against each other and students at other universities.

Currently, the most popular games are Valorant, League of Legends and Super Smash Bros. for Nintendo Switch. Although video games can be played at home, they’re often more fun to play with friends in person, says Ghobrial who goes by the username “Serp” (a reference to the serpentine Pokémon “Serperior”).

“When I joined the club as a member in first year, that’s honestly how I met a lot of people I’m friends with now,” he says.

“If you feel like it’s something you’d be interested in but feel shy – don’t be. Everyone in the club is welcoming and wants to have a good time.”

K-Pop Dance Crew

Thy Nguyen (centre), a linguistics major and member of University College and events officer in the K-Pop Dance Crew, teaches choreography at Hart House (photo by Geoffrey Vendeville)

Ada Huang, a student in life sciences at New College, became a fan of K-pop in 2013 when she discovered the girl groups SISTAR, AOA and Girls’ Generation.

Only a year earlier Korean rapper Park Jae-sang, better known as Psy, became an international sensation with the earworm, “Gangnam Style,” which overtook Justin Bieber and Katy Perry on the Billboard charts.

Today, K-pop has become so popular that supergroup BTS was invited to the Oval Office to address anti-Asian racism.

Huang says one of the reasons she was drawn to K-pop was bands’ use of “concepts” – the distinctive styles that groups use in their videos, lyrics and costumes – that range from “high school” to “cute.”

She joined the K-Pop Dance Crew in order to make new friends who shared a love of the genre and dancing. Together, they learn the steps to their favourite videos and sometimes share their performances on YouTube.

“I think what I really appreciate about K-pop,” Huang says, is “how talented these young people are, and their determination in following their dreams of becoming a singer.”

Instagram: @uoftkdc https://www.instagram.com/uoftkdc/?hl=en

Bikechain

Bo Huang, a graduate of the Rotman School of Management, fixes his bike at Bikechain, a campus cycling co-op on the St. George campus (photo by Geoffrey Vendeville)

On a typical afternoon at the Bikechain cycling co-op at the corner of Huron and College Streets, many grease-stained fingers are busy replacing punctured tubes and worn-out brakes.

The co-op is a place where students can turn to volunteers or full-time staff for guidance on bike repairs and even buy second-hand parts.

“It can be a little hectic, but it’s very collaborative. People end up helping each other out,” says Beth Austerberry, executive director of Bikechain.

Since 2005, the club has subsisted on student levies and donations to make cycling as affordable as possible for students who may already be living on a tight budget.

Bikechain is open four days a week for DIY repairs and once a week for drop-off repairs. �Թϱ�� students can also borrow a bike for free for one week at a time with a TCard and $100 deposit.

In addition to helping cyclists maintain their rides, Bikechain encourages people to discover the city on two wheels. The club recently began leading group rides to scenic locations in the GTA, including Ontario Place and Leslie Street Spit, a five-kilometre stretch of infill that juts out into Lake Ontario.

“What people like about us is that we’re a pretty social community space,” Austerberry says. “It’s partly about fixing your bike and partly about having fun with other people.”

Instagram: @bikechainut https://www.instagram.com/bikechainut/

Hart House Chess Club

Chess lovers of all skill levels are welcome to join the Hart House Chess Club, which offers lessons and drop-in nights (photo by Geoffrey Vendeville)

Members of the Hart House Chess Club like to say that it’s “where the kibitzer is king.”

In chess-speak, a kibitzer is a spectator who comments on games in progress.

Ahmed Khalf, the club’s communications director, says the motto – which appears on the back of their club t-shirt – speaks to the group’s friendliness.

“Basically, the club is for anyone who’s interested in chess. It doesn’t really matter what level you are,” says Khalf, a computer science major in the Faculty of Arts & Science and a member of Trinity College. Though the club includes players with the rank of FIDE Master and Candidate Master, any and all players are welcome.

Khalf says he only started playing “seriously” three years ago – part of a Queen’s Gambit-inspired influx of players.

The club has a long history – in fact, it was founded in 1895, even before Hart House opened. It runs a weekly drop-in on Fridays and offers lessons that come with the $25 annual membership fee.

Khalf says being a member isn’t just about learning to ambush your opponent’s king. “It’s not so much about the game as it is about the people around it,” he says.

Instagram: @hhchessclub, https://www.instagram.com/hhchessclub/

�Թϱ�� Trash Team

The �Թϱ�� Trash Team helps keep green spaces and waterways clean by picking up cigarette butts, plastic and other garbage (photo courtesy of the �Թϱ�� trash team)

A couple of years ago, Madeleine Milne was looking for an interesting pastime that would allow her to help her community.

The �Թϱ�� Trash Team – a science-based community outreach group of students, researchers and other volunteers – fit the bill perfectly.

Team members organize clean-ups in parks, ravines and along the waterfront by bagging heavy loads of plastic waste and other garbage. At Sir Casimir Gzowski Park on Humber Bay earlier this summer, Milne and the team collected tiny pieces of plastic, hundreds of cigarette butts and enough litter to fill 10 trash and recycling bags.

Keeping Toronto’s green spaces pristine is its own reward, says Milne, who studied ecology and evolutionary biology and works in the lab of Assistant Professor and Trash Team founder Chelsea Rochman.

But she adds that a key advantage of Trash Team membership is that it offers an opportunity to get involved while maintaining a flexible schedule during the busy school year. Students who would prefer not to get their hands dirty can volunteer to visit grade school classrooms to educate youth about plastic pollution.

On clean-up days, the Trash Team often draws attention from people in the neighbourhood, who ask how they can do their part to reduce plastic waste. “It feels good to know you’re having an impact on the community,” Milne says.

Instagram: @uofttrashteam https://www.instagram.com/uofttrashteam/

�Թϱ�� Skateboarders Club

Not even sub-zero temperatures prevent die-hard members of �Թϱ�� Skateboarders from practising (photo by Liam Ogilvie)

Skateboarding got an unexpected popularity boost during the pandemic, when gathering outside was the safest way to socialize, says Karna Goswami, president of the �Թϱ�� Skateboarders Club and third-year public policy major.

The �Թϱ�� club is open to everyone – students and the general public alike – and has a supply of extra boards for people to get a feel for the sport.

The club meets regularly and the most enthusiastic members skate throughout the year, as long as there’s no snow on the ground. During the winter, the club also hosts social events so members can stay in touch.

All skaters are welcome, whether they’re still learning to stand on four wheels or able to do a backside tailslide effortlessly.

“Skateboarding doesn’t just expose people to a sport,” Goswami says. “It helps you see the city in a more lively way. Also, doing sick tricks is a good time.”

EmpowART

EmpowART helps forge connections between students and seniors through therapeutic art workshops (photo courtesy of EmpowART)

A beach chair framed by trees faces a calm lake, where a setting sun peeks over the horizon and casts a warm glow on the water’s surface.

The tranquil scene is one of many that seniors have learned to paint in workshops led by the �Թϱ�� chapter of the EmpowART Foundation, a non-profit that uses art as a therapeutic tool in nursing homes and hospitals.

Founded one year ago, the �Թϱ�� chapter has taught workshops in person at seniors’ homes around the GTA and online. Student volunteers take a Bob Ross approach to teaching, giving step-by-step instructions to paint a picture of a desert, galaxy or still life. At the end of the workshop, participants put their artwork on display in their rooms or as part of a small exhibition.

Niha Burugapalli, a student in peace, conflict and justice studies and global health and member of Victoria College, co-founded EmpowART with Kenneth Yip, an assistant professor, teaching stream, in the department of cell and systems biology in the Faculty of Arts & Science.

Burugapalli says the art workshops give seniors a chance to mingle with other residents and youth while doing something out of the ordinary and exercising their creativity.

As for students, they learn how to use their skills to benefit others – and they make new and interesting friends in the process.

“I think that [seniors] really do enjoy spending time with youth and I think that’s a really important connection that we need to foster,” Burugapalli says. “Oftentimes, older folks are cast aside or neglected in society when they have a lot of amazing advice and things to share.”

UTSC Cheer Team

The UTSC Cheer squad has performed at �Թϱ�� Scarborough sports games and Pride Parade (photo by Geoffrey Vendeville)

You may have seen the �Թϱ�� Scarborough Cheer Team revving up crowds at basketball and hockey games, or maybe even dancing at the Pride Parade.

On a recent August night, the squad warmed up in a cheerleading gym in Scarborough with stretches and somersaults before going through a routine to the tune of Beyoncé’s Renaissance.

Prior to the pandemic, the team took part in cheer competitions for the first time and received no deductions from the judges for their performance. Now, new and returning students are planning a comeback.

Although competitive cheerleading generally requires co-ordination and skill, the club caters to everyone, says Jessica Fernandes, who studied philosophy at �Թϱ�� Scarborough.

“Our club is no-experience-needed,” she says. “We welcome people with absolutely no training, even no athletics at all … All bodies are welcome – anybody can do cheerleading.”

Instagram: @utsccheerleading https://www.instagram.com/utsccheerleading/?hl=en

Reef 'hope spots' may help rescue coral habitats damaged by climate change: Researchers

geoff.vendeville — Thu, 04 Aug 2022 15:54:01 +0000

Reef 'hope spots' may help rescue coral habitats damaged by climate change: Researchers

geoff.vendeville Thu, 08/04/2022 - 11:54

Cutline

A new study shows that connections between climate-resilient coral reefs can help recover biodiversity, even after projected mass bleaching events from climate change (photo by Renata Romeo)

Topic

Climate Change

With coral reefs imperiled by climate change, coral refugia – reefs in habitats that are protected from environmental stressors – may hold the key to sustaining these diverse underwater ecosystems.

A new study by researchers at the University of Toronto, Wildlife Conservation Society and National Research Council in Italy suggests these “coral reef hope spots,” connected to other reefs in networks that carry tiny larval coral on ocean currents, may help maintain and regenerate ocean biodiversity – even after projected mass coral bleaching events.

“Our results show how crucial it is to understand coral reef networks and how they may be affected by climate change, when designing future coral reef conservation strategies,” says Ariel Greiner, lead author of the study and a PhD candidate in the department of ecology and evolutionary biology in �Թϱ��'s Faculty of Arts & Science.

“We found that these coral reef networks may help maintain coral reef strongholds. We also encourage researchers to build off of this work and determine the locations of reefs that could act as stepping stones between these coral reef strongholds, as these reefs will hold the key to enabling these strongholds to preserve not just themselves but also the rest of the global coral reef habitat.”

In the study, which appeared in Global Ecology and Biogeography, scientists modelled coral larval dispersal connections between reefs. Also known as coral connectivity, these connections form networks that serve to transport larval corals over vast distances to shuffle the gene pool and help reefs recover from coral bleaching and other disturbances.

By modelling connectivity under different scenarios of climate change and future coral bleaching, the researchers provide a glimpse of how connections between reefs might change in coming decades – and the potential of those networks to reseed reefs that are lost. Their findings may help inform future conservation strategies as coral reefs suffer the effects of climate change, ocean acidification and overfishing. Alarmingly, some models predict 70 to 99 per cent of reefs risk long-term damage due to bleaching by 2100 or earlier, the researchers note.

The researchers' study pinpoints reefs that have the greatest potential to regenerate others, helping direct limited resources for conservation at a crucial time for climate action (photo by Matt Curnock)

Some existing climate-resilient coral reef strongholds are expected to have the best chance of surviving environmental stressors. If they do, the researchers found that present-day connectivity – grouped into six major networks of interconnected reefs worldwide – will be largely preserved, even if only the most climate-resilient coral reef strongholds (representing about 30 per cent of original coral reef cells) remain.

“Strategic conservation action is crucial in the face of climate change,” says Emily Darling, director of Coral Reef Conservation at WCS and an adjunct professor in the department of ecology and evolutionary biology, as well as study co-author. “Our study shows that biological connections between reefs can increase the ability of corals to recover from climate shocks and are a call to action to boost the health and function of key “source” reefs in climate-resilient networks.”

However, the researchers strike a note of caution, saying that not all coral reef habitat can be restored if only about 30 per cent of coral reef habitat is preserved “even under an optimistic reseeding paradigm.” Even if stepping stone reefs are also preserved, it will still take “several generations to reseed all reachable reef cells,” they add.

Nevertheless, the researchers say the study will help inform conservation strategies by highlighting the importance of reef connectivity to ensure their resilience in the face of climate change.

This research was supported by Bloomberg Philanthropies, The Tiffany & Co. Foundation, and by the National Science and Engineering Research Council (NSERC) Canada Graduate Scholarships and Canada Research Chairs.

With files from the WCS.

Whales' eyes offer glimpse into their evolution from land to sea: �Թϱ�� researchers

Christopher.Sorensen — Thu, 28 Jul 2022 15:37:02 +0000

Whales' eyes offer glimpse into their evolution from land to sea: �Թϱ�� researchers

Christopher.Sorensen Thu, 07/28/2022 - 11:37

Cutline

(photo by Shasin Satuei from Pexel via Canva)

Neil Macpherson

Topic

Cell and Systems Biology