A study led by Malin Pinsky, an ecology and evolutionary biologist at UC Santa Cruz, reveals that rising temperatures caused by climate change have a profound and dual impact: they destabilize animal populations and speed up these changes as temperatures rise more rapidly.
Published on January 29 in Nature, the research, conducted by an international team, explores how temperature fluctuations – whether warming or cooling – affect the composition of species in ecosystems. The findings suggest that neither behavioral adaptation nor changes in species interactions can prevent the alteration of species composition in the face of increasingly rapid temperature shifts.
"It's like shuffling a deck of cards, and temperature change now is shuffling that deck faster and faster," said lead author Malin Pinsky. "The worry is that eventually you start to lose some cards."
This research is notable because the effects of temperature changes on land and freshwater ecosystems have often been unclear. While the impact of temperature changes on ocean species has been more apparent and easier to measure, land-based plants and animals adapt more subtly, the researchers explained.
Unlike marine life, terrestrial species can often migrate short distances to find more suitable climates. Though this may ease some of the effects of temperature changes, the study concludes that these species are still vulnerable to destabilization and replacement due to rising temperatures. The paper focuses on species turnover – the natural loss and gain of species – finding that the pace of this turnover is accelerating because of more rapid temperature changes.
If this trend continues, species loss and ecosystem degradation are likely, the study warns. To avoid these consequences, the researchers suggest reducing global warming, protecting diverse landscapes, and minimizing environmental degradation. Such measures would not only preserve biodiversity but also improve air and water quality, and support abundant wildlife.
"Temperature affects everything from how fast the heart beats to how flexible and porous our cell membranes are; from how much food animals eat to how fast plants grow," said Pinsky. "Temperature is in many ways the metronome for life."
The Importance of Habitat Diversity
The study also highlights how ecosystems with more varied habitats are better able to withstand temperature fluctuations. For example, in a scenario where a person overheats in an open field, there is nowhere to seek refuge. But in a forest, moving into the shade of a tree could provide much-needed relief. Similarly, animals and plants rely on the variation in their environments to shield themselves from extreme temperature swings. Without these "temperature escapes," they are at higher risk of being wiped out or replaced.
Ecosystems with less habitat diversity are particularly vulnerable to these changes, and understanding these dynamics will help identify which environments require the most protection. This research underscores the need for focused conservation efforts to safeguard ecosystems most threatened by rapid temperature changes.
"Establishing this explicit link between rates of climate change and rates of species turnover allows us to better understand how changing temperatures can impact different ecosystems," said senior author Shane Blowes from the Centre for Integrative Biodiversity Research (iDiv) in Germany. "Pinpointing factors that impact the rate of local species replacement can help prioritize conservation actions."
Human Impact on Species Turnover
The study also found that human activities – such as land use changes, pollution, and the introduction of invasive species – exacerbate the effects of temperature shifts. These actions decrease landscape diversity and put additional stress on species already vulnerable to temperature changes.
To protect ecosystems and the benefits they provide, Pinsky emphasizes the importance of preserving natural habitats, reducing pollution, and controlling the spread of invasive species. In marine environments, reducing fishing pressure and safeguarding habitats can also aid conservation efforts.
The study's other contributors include Helmut Hillebrand from the University of Oldenburg, Jonathan Chase from iDiv and Martin Luther University Halle-Wittenberg, and researchers from various institutions including the Institute of Biodiversity at Friedrich Schiller University and the University of Helsinki.
Research Report:Warming and cooling catalyse widespread temporal turnover in biodiversity
