The process of evolutionary divergence is ultimately responsible for the generation of our planet’s extraordinary biodiversity from just a single ancestor. Systematics is the study of the relationships that unite all organisms on earth – i.e. the tree of life. Systematists discover and describe species new to science, reconstruct phylogenetic relationships, and test hypotheses about the tempo and mode of evolution over grand temporal and spatial scales. The Biodiversity & Systematics Group advances knowledge of the tree of life and macroevolution using tools from genetics, anatomy and morphometrics, geology and palaeontology, mathematics, statistics, and field biology. Recent advances in genomics, morphological imaging, and computational biology have led systematics to become one of the fastest growing areas in biology. 

How does present-day biodiversity compare to that of the deep past? What ecological factors or adaptive innovations promote diversification? Does evolution repeat itself when the “tape of life” is replayed on different islands or continents? Do traits that are adaptive in the short term ultimately increase long-term extinction risk?

In seeking answers to these questions, the Biodiversity & Systematics Group enriches our understanding of the diverse world we live in, and illuminates the branching evolutionary path that led to present-day biodiversity. Phylogenetic insights provide vital historical context for research across biological subdisciplines, from molecular biology to community ecology, and developments in systematics have led to major advances in the applied sciences, including invasive species control, epidemiological forecasting, and vaccine development.

The Earth has entered a new epoch known as the Anthropocene in which human impacts now dominate changes to biodiversity. Factors such as global climate change, invasive species, pollution, and habitat loss have led to a rise in species extinctions that may now be as high as 100 to 1000 times above normal levels. The biodiversity that is being lost does not only alter the composition of ecosystems, but it also affects the capacity of ecosystems to provide people with such basic necessities as clean air, water, and food. EEB researchers (professors, postdocs, graduate, and undergraduate students) are working to understand and find ways to mitigate these changes to biodiversity. Current projects involve fieldwork, experiments, and modeling to understand the processes that generate and maintain biodiversity, how to design networks of protected areas that best conserve biodiversity, how the demography and distribution of species respond to climate change, the emergence and spread of infectious diseases, the pervasive effects of plastic pollution on rivers, lakes, and oceans, and the ecology of sustainable fisheries and other aquatic ecosystem services. This work of EEB researchers does not end when the science is done, but is carried through to communication and engagement with the public, industry, conservation organizations and governments to help inform how management and policy changes can improve biodiversity conservation.

The parasites and pathogens that cause disease are complex and responsive organisms — more like polar bears than pollutants — that interact with their environment and other species in it. It is these interactions with other species that influence, for example, if a new disease will spillover from wildlife to humans or from farmed to wild species, the severity of that disease in its new host, and how the distribution of disease will shift with climate change. Such interactions are at the core of ecological research. Meanwhile, evolutionary approaches to disease answer questions about why parasites do harm to their hosts, how the severity of disease or infectiousness may change in response to public health interventions, and how best to slow or avoid drug resistance or vaccine escape.

Researchers in EEB at the University of Toronto are using a combination of mathematical and statistical modelling, experimental lab work, and field studies to answer some of these fundamental questions in disease ecology and evolution. Current projects include quantifying the challenge of parasites for maintaining food security and conserving wildlife, predicting the spread of tick-borne diseases in a warming world, and identifying the traits of parasites that may pre-dispose them to be less responsive to drug treatment.

Ecology studies the interactions among individuals and with the environment. It examines questions such as how populations invade, persist, or go extinct, how communities are assembled and maintained, and how energy and nutrients flow through ecosystems. As such, ecology encompasses multiple levels of biological organization, ranging from how the natural history of a species relates to its population growth, to how predation and competition structure food webs, to how ecosystems absorb and release carbon. Ecology forms the basis for a diversity applications, such as the interactions between viruses and an immune system in medicine, how an emergent disease spreads through a population, how to protect and recover endangered species, the optimal harvesting of renewable resources such as fisheries and forestry, and understanding and mitigating climate change. Ecologists in EEB use a variety of methodological approaches, particularly fieldwork, laboratory experiments, mathematical models, and statistical analysis of global datasets. 

Evolutionary biology is the study of the diversity of life and the processes that create it. The Evolutionary Genomics group approaches these topics by integrating knowledge and methods from molecular biology, mathematics, physics and computer science.

Modern high-throughput DNA sequencing and computing power make today an incredibly exciting time to decipher the evolutionary process with genomes. Combining these technical tools with ingenuity and passion, UofT’s evolutionary genomics researchers are pushing the forefront of this field to address fundamental questions that their predecessors only dreamed about and tackling new questions that previous generations never imagined.

How do new species evolve? How do pathogens co-evolve with their hosts? How repeatable is adaptive evolution? How do the chromosomes that determine the two sexes come to be? Why reproduce with two parents rather than one (as many plants and some animals do)? How are all of these phenomena encoded in genomes?

These fundamental scientific inquiries are critical to deriving solutions to many problems in applied sciences as well, such as in mapping human disease genes in medicine, predicting the ability of species to adapt to rapid climate change, and combating rapid adaptation of drug-resistant parasites and herbicide-resistant weeds.

The function and evolution of those organismal traits underlying morphological, behavioural and physiological systems.