How Disabled Apes Learn to Cope Single Handed With Life in Forest

Pandora the gorilla copes with life singlehanded. On one hand, she has one working thumb. The rest of her right hand is cut across the palm by a snare. The other hand has two fingers that work.

And yet Pandora survives in the Budongo forests of Uganda.

So do a number of disabled chimpanzees, according to Dick Byrne, a psychologist at St Andrews University, and his student Emma Stokes. Up to a quarter of all adult chimpanzees in Africa may have been injured in some way, often by traps and snares set for other animals.

But the scientists found that, like humans but unlike monkeys, disabled apes develop strategies for coping. One chimpanzee, Tinka, also had severe injuries to both hands, and just one functioning thumb. He learned to use his mouth as a tool instead. Injured chimpanzees could also climb trees singlehanded, according to Professor Byrne.

"They can get up to the tops of trees. They could use the other hand as a hook, and all of the chimps that Emma studied could forage in the canopy ... But able-bodied chimps do a lot of hanging below the canopy, and feeding with the other hand - which is out."

Chimpanzees are humanity's closest relatives. The research could throw light on the origins of human intelligence. It will throw even more light on the hazards that now threaten the survival of the great apes.