University of Toronto Mississauga
Cities are unique ecosystems full of environmental challenges not found anywhere else in nature. Concrete and steel infrastructure and carbon emissions trap heat in cities, leaving them up to 10 degrees warmer than outlying rural areas.
Marc Johnson studies how organisms adapt and survive in urban environments. The University of Toronto Mississauga researcher wondered if plants growing in downtown Toronto would be genetically different from those in surrounding rural areas. Using common white clover, which exhibit pronounced genetic changes that allow them to thrive in varied climates, Johnson’s study showed that differences in temperature between urban and rural environments cause dramatic genetic changes in the plants.
Now, what began as a sampling of a few North American cities has exploded into an international survey: the Global Urban Evolution Project, or “GLUE,” brings together more than 270 collaborators studying 160 cities on every inhabited continent, in what is believed to be the largest collaborative project in evolutionary biology ever attempted. Johnson’s lab has also expanded its work to study how a wide diversity of plant and animal species evolve in response to cities, pointing the way to changes for healthier cities where all life can flourish.