Researchers at the New York Institute of Technology report that, with one foot, sloths can exert a force “far beyond” the grip of man, relative to their body weight. Melody Young, a PhD candidate at the school, and her team measured the grip of each foot on five brown-throated sloths at The Sloth Sanctuary in Costa Rica.
As they dangled from a measuring device, the sloths squeezed each fore and hind foot with a force averaging as much as 100 percent of their body weight. That’s roughly twice the proportional grip strength of humans and primates.
Some individual foot tests registered nearly 150 percent grip strength, according to the findings published in the Journal of Zoology.
Dr. Edwin Dickinson, also of the New York Institute of Technology, says sloths have reduced musculature in their core compared with other mammals. However, the researchers adds that muscles near their feet have fast-contracting fibers associated with heightened strength.
“That power can be crucial given their leisurely pace,” Dr. Dickinson says in a statement to SWNS.
“A sloth might be in a situation where if a branch fails, they may only be able to get one hand or foot on,” adds Professor Adam Hartstone-Rose from North Carolina State University.
The study also revealed a surprise in that the sloths had a consistent and unexplained left-side bias in their strength, which is the opposite of primates.
South West News Service writer Stephen Beech contributed to this report.