The Fragile and Fascinating World of Frogs
Amphibians and reptiles have long captivated biologist Dr. Adam Algar. These cold-blooded animals—known as ectotherms—can help us understand how animals evolved, how they survive in ecosystems across the globe, and how they're responding to Earth's warming environment.
Dr. Algar joined Lakehead in 2021 after spending 10 years at the University of Nottingham in the United Kingdom where his research focused on lizards that are native to the Caribbean and Southeast Asia.
"Are ectotherms struggling, or is climate change enabling them to expand their geographic ranges?" Dr. Algar asks. "We need to understand how species are living now to better predict how they'll be affected by climate change. Gathering this information is crucial to developing conservation policies and strategies."
Dr. Algar primarily studies frogs living in northwestern Ontario. "It's a really exciting ecosystem because northwestern Ontario is a boreal forest in the transition zone from hardwood to coniferous trees."
He has a team of graduate and undergraduate researchers who are part of his laboratory dedicated to studying the ecology and evolution of ectotherms. One current project, in partnership with the Lakehead Region Conservation Authority (LRCA), is recording and monitoring frog and bird calls to determine which species are present and track long-term changes. "We're already learning about what affects their breeding season," Dr. Algar says.
It's Not Easy Being Green
A gray tree frog hangs out at a pond. "I became really interested in animal biodiversity after growing up running around the woods of Cape Breton, Nova Scotia," Dr. Algar says. "Globally, we probably don't know about more than half of the species that exist."
One of the reasons Dr. Algar studies frogs is that they're sensitive to environmental changes. "They're the canary in the coalmine—an early warning sign of what's happening in an ecosystem."
Specifically, he investigates how frogs behave throughout the short northwestern Ontario breeding and growing season when they are active. Dropping temperatures prompt frogs to bury themselves under leaf litter and wait for snow to insulate them. "That's why it's a problem when we have cold winters and no snow." During the winter, frogs' hearts almost stop and they go into a state of torpor. Incredibly, several frog species create antifreeze to replace much of the water in their bodies to stop their cells from bursting.
The gray tree frog is one of the species Dr. Algar's lab is studying. "They're a stunning little frog, one to two inches in length, with bumpy skin that changes colour from grey to vibrant green. They also have bright yellow legs and large toe pads to stick to trees." Their range begins in Texas and, in recent decades, has expanded into the Thunder Bay region. "Any species that inhabits such a vast area must be harbouring some fascinating eco-evolutionary secrets," Dr. Algar says.
If people are lucky enough, they might see these frogs stuck to the windows of their camps on summer evenings. "They're attracted to light because the insects they eat are attracted to light," he explains. "And they start calling around 10 o'clock at night. It's a loud short trill often mistaken for a bird."
Ectotherms like this brown anole lizard (Anolis sagrei) get their heat from their environment, often by basking the sun, instead of generating it internally like mammals. "This means they have a low metabolic rate and require less food. But when the temperature tips too far, either hot or cold, it can have deadly consequences," Dr. Algar says.
Dr. Algar's research is dissolving traditional boundaries between localized field ecology and large-scale macroecology that uses modelling and large datasets. "I use our fieldwork data to test and inform our macroecology models to see if the models are working.
We also measure how temperature affects how far frogs can jump and how fast tadpoles can swim. It's like the animal Olympics."
Dr. Algar engages in this painstaking work to lay the foundation for conservationists. "I don't want to live in a world where springtime is no longer greeted by the choruses of frogs."
Lakehead University is in the top 10 per cent globally of universities making an impact by advancing sustainability and positive societal change and was named the top-ranked university with under 10,000 students in Canada and North America in the Times Higher Education Impact Rankings. These prestigious rankings assess universities' success in delivering on the United Nations 17 Sustainable Development Goals (SDGs) to solve our planet's most pressing challenges. Dr. Algar's work addresses SDG 13: Climate Action, SDG 14: Life Below Water, and SDG 15: Life on Land.