If we pay closer attention to how birds, rabbits and termites transform their local living spaces in response to varying climate conditions, we could become much better at predicting what impact climate change will have on them in future.
This is according to a group of researchers* from the Universities of Montana and Wyoming in the United States, the University of Tours in France and Stellenbosch University (SU) in South Africa. They examined how animals' ability to respond to climate change likely depends on how well they modify their habitats, such as the way they build nests and burrows.
The findings of their study were published recently in the high-impact journal Trends in Ecology and Evolution.
"It's crucial that we continuously improve our ability to predict and mitigate the effects of climate change. One of the ways we can do this is by gaining a better understanding of how animals influence their own small-scale experience of climate at the level of individual members in a population," says one of the researchers, Prof John Terblanche from SU's Department of Conservation Ecology and Entomology.
Terblanche and his co-authors mention that in order to enhance the predictive power of typical contemporary climate change models, it will be important for biologists to understand how animals transform their living space locally in response to climate variability.
"Improving such models will be key to forecasting the effects of climate change on species, and to predict future effects, including how species ranges may shift and what the relative risks of extinction are for different animal species with high levels of precision."
They add that knowing which species will proliferate with climate change is central to understanding pest outbreaks on crops, or disease vectors changing risks for humans.
"Climate change will impact the spread of disease vectors, the health of marine and terrestrial biomes around the world and will influence whether agriculture and fishing will be able to continue supporting human populations, as they have in the past."
In their study, the researchers point out how some animals have found unique ways to protect themselves against extreme climate conditions.
"Many animals dig burrows, construct nests for themselves or their offspring, build homes for entire colonies (ants and termites), induce plants to produce galls, build leaf mines, or simply modify the structure or texture of their local environments.
"For example, birds build nests to keep eggs and chicks warm during cool weather, but also make adjustments in nest insulation to keep the little ones cool in very hot conditions. Mammals, such as rabbits or mice, sleep or hibernate in underground burrows that provide stable, moderate temperatures and avoid above-ground conditions that often are far more extreme outside the burrow.
"We've also seen how termites and ants build mounds that capture wind and solar energy to drive airflow through the colony, which stabilizes temperature, relative humidity, and oxygen level experienced by the colony."
The researchers say these modifications, known as extended phenotypes, filter climate into local sets of conditions immediately around the organism - 'the microclimate', which is key for a better understanding of the impact of climate change.
"Two features of microclimates are important. First, microclimates typically differ strongly from nearby climates, which means that the climate in an area may provide little information about what animals experience in their microhabitats. Second, because extended phenotypes are built structures, they often are modified in response to local climate variation, and potentially in response to climate change."
The researchers call for a renewed effort to understand how extended phenotypes mediate how organisms experience climate change. "We need a much better understanding of how much animals can adjust these structures in response to varying climate conditions," says Terblanche.
"Another key challenge is to understand how much flexibility there is in extended phenotypes, and how rapidly they can evolve. At this point, we pretty much have no idea whether these processes can keep up with climate change," adds lead author Art Woods from the University of Montana.
* Source: Woods, HA; Pincebourde, S; Dillon, ME; & Terblanche, JS 2021. Extended phenotypes: buffers or amplifiers of climate change? Trends in Ecology and Evolution: doi.org/10.1016/j.tree.2021.05.010 1
*Art Woods (University of Montana), Sylvain Pincebourde (University of Tours), Michael Dillon (University of Wyoming) and John Terblanche (Stellenbosch University).
Trends in Ecology & Evolution