The survival of sloths is under threat due to climate change, according to a new study.
The famously slow-moving — and adorable — creatures of Central and South America could die out if temperatures rise.
The research, conducted by scientists studying the metabolic response of sloths to rising temperatures, suggests that the energy limitations of these animals could make survival untenable by the end of the century, particularly for high-altitude populations.
Lead researcher Dr. Rebecca Cliffe said: “Sloths are inherently limited by their slow metabolism and unique inability to regulate body temperature effectively, unlike most mammals.
“Our research shows that sloths, particularly in high-altitude regions, may not be able to survive the significant increases in temperature forecast for 2100.”
The study, titled “Sloth Metabolism May Make Survival Untenable Under Climate Change Scenarios,” investigates how two-fingered sloths (Choloepus hoffmanni), living in both highland and lowland regions, respond to varying ambient temperatures.
Using indirect calorimetry, researchers measured oxygen consumption and core body temperature of sloths under conditions mimicking projected climate changes.
Their findings indicate a troubling future for sloths, especially those residing in high-altitude areas.
By the year 2100, with projected temperature increases between 2°C (35.6°F) and 6°C (42.8°F) in sloth habitats, high-altitude sloths are predicted to face a severe metabolic burden.
Their limited energy-processing ability, combined with minimal geographical flexibility, may prevent them from adjusting to the warming climate.
Sloths’ slow digestion rate, which is up to 24 times slower than other similar-sized herbivores, poses another challenge.
Any increase in metabolic demand due to climate change cannot easily be met by increased food intake, making it difficult for sloths to maintain energy balance.
The study suggests that while lowland sloths may cope by shifting their ranges to higher altitudes, highland sloths are geographically constrained and may not have this option.
The research team are calling for further investigation into adaptive strategies and conservation policies that can help mitigate the risks sloths face in a rapidly warming world.
The study is published in PeerJ – the Journal of Life & Environmental Sciences.
