Sloth metabolism may make survival untenable under climate change scenarios.

Although climate change is predicted to have a substantial effect on the energetic requirements of organisms, the longer-term implications are often unclear. Sloths are limited by the rate at which they can acquire energy and are unable to regulate core body temperature (T) to the extent seen in most mammals. Therefore, the metabolic impacts of climate change on sloths are expected to be profound.

The metabolic response of the sloth to temperature.

Poikilotherms and homeotherms have different, well-defined metabolic responses to ambient temperature ( ), but both groups have high power costs at high temperatures. Sloths () are critically limited by rates of energy acquisition and it has previously been suggested that their unusual departure from homeothermy mitigates the associated costs. No studies, however, have examined how sloth body temperature and metabolic rate vary with .