Hoffmann's two-toed sloth (Choloepus hoffmanni) become extinct before 2100 due to climate change

NEWS - Sloths may not survive the significant temperature increases predicted to occur by 2100. The notoriously slow-moving creatures native to Central and South America may face an existential threat from climate change, researchers say.

Research examining the metabolic response of sloths to rising temperatures suggests that the animals’ energy constraints could make survival untenable by the end of the century, particularly for high-altitude populations.

Rebecca Cliffe of the Sloth Conservation Foundation in Derbyshire, United Kingdom, and colleagues investigated how Hoffmann’s two-toed sloths (Choloepus hoffmanni), which live in highland and lowland areas, respond to varying ambient temperatures.

Using indirect calorimetry, the researchers measured the sloths’ oxygen consumption and core body temperature under conditions that mimic projected climate change. The findings suggest a troubling future for sloths, particularly those living in high-altitude areas.

"Sloths are limited by their slow metabolism and inability to regulate body temperature effectively, unlike most mammals. We show that sloths, especially in high-altitude areas, may not be able to survive the significant temperature increases predicted to occur by 2100," Cliffe said.

Original research

Cliffe RN, Ewart HE, Scantlebury DM, Kennedy S, Avey-Arroyo J, Mindich D, Wilson RP. (2024). Sloth metabolism may make survival untenable under climate change scenarios. PeerJ 12:e18168, DOI:10.7717/peerj.18168

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