Michael Kearney is a Professor in the School of BioSciences at the University of Melbourne whose research is focussed on understanding and predicting how Australia’s major mammal and insect pests will respond to climate change.
If you’re doing a jigsaw puzzle, it’s always helpful if you start with the edge pieces. In the same way, if you’re studying the way an organism interacts with its environment, it’s important to begin by understanding its physical limitations.
How hot can an animal get and still survive? How much water can it afford to lose? How long can it go without food? How do organisms time their life cycle to match resources and avoid hazards? What are their tricks to survive?
My Australian Research Council (ARC) Laureate project is about understanding how different kinds of animals are responding to climate change. This is a pure research puzzle I’m obsessed with intellectually, but which has great practical importance.
What I’m trying to do as an ecologist is to bring physical and biological principles together to find the edge pieces of the puzzle. There’s always a lot of complexity in biology but, if we know where the limits are, we can narrow down the problem.
It was only towards the end of my undergraduate degree that I discovered the power of physics to solve puzzles in ecology. For example, if you treat the organism as a physical problem of heat exchange – how much heat is going in, how much heat is going out – you can then calculate what that means for their survival.
We ecologists don’t get trained in these physical concepts and methods, but they’re really effective for making inferences about what’s going to happen in new environments.
Climate change is already creating environments for which we have no precedent. To predict what will happen under these novel conditions, we can’t rely on descriptions of what’s happened in the past. We need an approach that is based on an understanding of the reasons underlying the patterns we observe so we can forecast what will happen with greater confidence.
For example, foxes don’t roam all the way to the north of Australia. Why do they stop just where monsoonal rains kick in, and how will this change in the future? That’s a very tantalising question I want to answer.
Another big question: when’s the next locust plague? Can we predict it? The last one was in the summer of 2010-11. There hasn’t been one since and we don’t know why, but we need to. Locusts are grasshoppers that change their behaviour and sometimes even their appearance when they reach high density. They seek each other out, marching together in bands when young, and flying around together as adults. When they reach extremely high densities, they can take out a farmer’s wheat crop in very short order.
Understandably, there’s a very active campaign to control locusts. In fact, there’s a government department called the Australian Plague Locust Commission, which is specifically focused on that species, regularly surveying for them, keeping an eye on where they’re going and making forecasts of what should happen next. My ARC laureate project will collaborate with the Commission scientists to see if we can push the boundaries of our predictive capacity, developing enhanced physical modelling of the locusts and their response to the climate.
Science, animals and climate change
I knew from a very young age that I wanted to focus on science and animals in my career. I grew up in the outer eastern suburbs of Melbourne, with a creek just down the road. I spent my summers trying to find cicadas and blue-tongue lizards. One magical day I found a red-bellied black snake near the creek – I became obsessed with snakes in my teens, with a plan to do a PhD on them.
Then I got to uni and was exposed to other exciting topics in science – I almost became a geologist for a while there, but I stuck with the original plan and went down the path of ecology. I’ve always loved being outside and encountering wildlife, particularly animals – I get enormous satisfaction in using my knowledge about an organism to find it in nature, then asking the scientific questions of how it is surviving.
Climate change is throwing up huge challenges in understanding the puzzle of how organisms will respond – those we love and those that cause us problems. I hope my work helps us solve this puzzle so we can anticipate these challenges and respond effectively.
Also in this ARC Laureate Fellows series: Jeffrey Walker
