‘Science and possibility’: UTSC student steps towards research career with national funding program

When Roselaide Decker first started at the University of Toronto Scarborough, she made a list of research programs to pursue. A top item on that list was the Natural Sciences and Engineering Research Council of Canada (NSERC) Undergraduate Student Research Award (USRA) program.

It became the first goal Decker accomplished when Cosima Porteus, an assistant professor in the department of biological sciences, encouraged her to apply to the program – and pursue the opportunity in her lab.

“The program is not just about science, but also about possibility,” says Decker, a 2024 USRA recipient who is now a third-year biological sciences student.

“As a second-year undergrad at the time, I had only completed two semesters of group research lab time so taking on independent study was a big step.” 

Administered by Canada’s three granting agencies, the USRA program offers awards valued at $6,000 for students in participating Canadian institutions to develop their potential for a research career. The program supports research in health, natural sciences and engineering, or social sciences and humanities. 

Working in Porteus’ comparative physiology lab, Decker investigated how lamprey – a jawless, eel-like fish species found in freshwater and saltwater environments –  sense changing aquatic conditions. To do this, she examined the distribution patterns of neuroepithelial cells (NECs). Found on gills, these sensory cells help fish detect oxygen (O₂) and carbon dioxide (CO₂) levels to survive. 

As CO₂ levels rise due to anthropogenic stressors, increased concentrations can significantly harm fish, primarily by causing water acidification, which disrupts their behaviour and development. However, sea lamprey, who are invasive to the Great Lakes, resemble ancestral fish as they have evolved 360 million years ago. Knowing if lamprey have NECs will contribute to informing the understanding of how fish sense their environment and when this sense evolved. 

“As lamprey develop from ammocetes (larvae) to the juvenile stage, they undergo significant environmental shifts as they move from estuaries deeper into the open ocean, and we also wanted to know how this development impacted the morphology of their gills and sensory cells,” Decker says. 

From an evolutionary perspective, lamprey can also tell us if the ancestors of fish utilized these cells to sense their environment. 

By applying immunochemistry techniques to label serotonergic NECs, synaptic vesicles and neuronal innervation on lamprey gills, Decker built on research conducted by a  previous undergraduate student in the lab to confirm that the first gill arch contains a higher concentration of NECs compared to the more posterior  gill arches. 

Using confocal microscopy imaging to compare the distribution and cell size of NECs in ammocetes compared to juvenile lamprey, Decker found that the NECs of juveniles were larger compared to those of ammocetes (larvae). “This suggests that as they grow and live in open ocean, it becomes more important to effectively detect O2 and CO2 levels,” Decker says “and from an evolutionary perspective of lamprey, it tells us that the ancestors of fish also utilized these cells.”

While Decker’s USRA placement has concluded, she continues to work in the lab for an independent supervised study to understand the NEC distribution of two other species, sculpins  and gunnels, which are marine fish that live on the west coast of North America.  She is using differences in NEC distribution and sizes to underscore an evolutionary map from lamprey as a more “primitive” species to later evolved species like gunnels. 

‘The aim of knowledge is action’

Decker applied for the program through its pathway for Black undergraduate students, which is part of a broader commitment to creating a more equitable and inclusive research landscape in Canada. The USRA program currently offers dedicated opportunities for both Black and Indigenous undergraduates.

“It’s necessary that there are diverse people in science because our perspectives and ideas can only improve it,” Decker says.

Participating in the program brought Decker closer to achieving her goal of a career in science. She aspires to be a humanitarian family physician, aiming to serve communities in rural and conflict zones in West Africa. In 2024, she founded the campus’ Humanitarian Action Network of Students” to encourage student involvement in global humanitarian work.

The USRA program equipped her with the necessary tools for effective advocacy, with science as a valuable tool.

“The USRA program further motivated my interest in pursuing translational research in medicine to improve health outcomes,” Decker says.

“As I pursue a career in science and research, I maintain the belief that the aim of knowledge is action.”