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A 2018 study investigating the hand posture of 77 mountain gorillas at Bwindi Impenetrable National Park ( 8 % of the population ) found that knuckle walking was done only 60 % of the time , and they also supported their weight on their fists , the backs of the their hands / feet , and on their palms / soles ( with the digits flexed ) .
 Bwindi Impenetrable National Park
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Answer:
 Bwindi Impenetrable National Park