By Don Campbell

When Zakee Sabree talks about microbes, he doesn’t start with disease. He starts with collaboration.

Animals, he explains, arrived on Earth long after bacteria had already established themselves. Ever since, animals and microbes have been evolving together—sometimes in conflict, but often in quiet co-operation. Understanding those relationships, and what they reveal about health, development and diversity, sits at the heart of Sabree’s research.

Now an associate professor at U of T Scarborough, Sabree studies how microbes living in animal guts shape growth, development and evolution. His work uses insects, particularly cockroaches, as a powerful tool to explore these questions.

“Animals are really phenotypes of relationships,” he says. “We tend to think of an organism as a standalone thing, but what we’re actually seeing is the outcome of constant interaction with microbes.”

Sabree’s research focuses on the gut microbiome, which are the vast and diverse communities of bacteria living inside digestive systems. While the microbiome has become a popular buzzword in human health, much of what scientists know still centres on illness, specifically which microbes cause disease, and how to stop them.

Sabree is interested in the bigger picture.

“Whether it’s microbes in a gut or people in a city, the question isn’t just what’s different, it’s what those differences make possible.”

In non-technical terms, his lab asks fundamental questions about how microbes shape animal life: what happens when an animal’s microbiome changes, whether greater microbial diversity supports healthy growth and development, and why the same microbes appear in animals living continents apart.

To tackle those questions, Sabree’s lab uses cockroaches as a model system. While they may not sound glamorous, cockroaches share striking similarities with humans when it comes to gut microbial diversity.

His team can raise cockroaches completely free of microbes, then introduce carefully selected microbial communities. Using simple camera systems and image-based analysis, they track how long it takes the insects to grow from juveniles into “teenagers,” a well-defined developmental stage. Changes in growth rate, gut structure and gene activity offer clues about which microbes are helping, which are harmful, and which may be redundant.

The broader implications extend far beyond insects. Sabree’s work feeds into ongoing debates about diet, gut health and microbial diversity in humans, particularly claims that less diverse microbiomes, often linked to highly processed diets, automatically lead to poorer health.

“My guess is that it’s more complicated than that,” he says. “We need systems that let us test these ideas carefully before we make broad assumptions.”

Sabree’s fascination with microbes grew out of an unexpected place: the kitchen. Raised in Washington, D.C. by parents and grandparents who loved to cook, he spent much of his childhood watching meals come together, even if he was a picky eater himself. As an undergraduate at Howard University, he was on the verge of leaving science altogether when a course on food microbiology changed his mind.

“That collaborative environment shaped how I run my lab. You need a lot of cooks in the kitchen.”

Learning that microbes were essential to the foods he loved, from fermented vegetables to soy products, sparked a lasting curiosity. During graduate school, he worked in professional kitchens, learning fermentation firsthand while completing a PhD in microbiology. The parallels between cooking and research – trial and error, creativity, teamwork – stuck with him.

“That collaborative environment shaped how I run my lab,” he says. “You need a lot of cooks in the kitchen.”

Though he knew little about Scarborough before arriving last semester, the move has already made an impression. The campus’s proximity to nature, the burgeoning One Health initiative, and the surrounding community’s cultural and culinary diversity all resonate with him.

“I’m blown away by the food scene here,” he says. “But more than that, I’m excited about training students who reflect the future of Toronto and Canada.”

For Sabree, U of T Scarborough’s community-focused mission aligns naturally with his research philosophy: diversity isn’t just about who’s present, but about how different elements work together to build a resilient system.

“Whether it’s microbes in a gut or people in a city,” he says, “the question isn’t just what’s different, it’s what those differences make possible.”

Originally published on February 27, 2026, on University of Toronto Scarborough News.