Johannesburg – Watch out Chad le Clos, video evidence has emerged of apes swimming and diving in water. This, say researchers Renato Bender from the University of the Witwatersrand and Nicole Bender from the University of Bern, shows that previously believed distinctions between humans and apes may not be as absolute as previously believed. The researchers studied a chimpanzee and an orangutan in the United States who were raised by humans and learned to swim and dive. The animals swim using a method similar to breaststroke. “We were extremely surprised when the chimp Cooper dived repeatedly into a swimming pool in Missouri and seemed to feel very comfortable,” said Renato Bender. The orangutan, Suryia, lives in a private zoo in South Carolina, and can swim freely up to 12 metres. There are subtle differences in their swimming style; Cooper the chimpanzee moves the hind legs synchronous while Suryia moves them alternatively. The researchers believe this swimming style, so close to that of humans, may be related to the adaptation experienced by primates from living in trees. Most mammals use the so-called dog-paddle to keep head above water when swimming. Apes and primates in zoos have often been kept in their enclosures by surrounding them with deep moats of water. This evidence indicates a different strategy may be required as researchers re-assess what they previously believed about the relationship between apes and water. “It was very surprising behavior for an animal that is thought to be very afraid of water,” said Renato Bender, speaking about Cooper’s tendency to dive deep under the water to collect objects. “The behavior of the great apes in water has been largely neglected in anthropology. That’s one of the reasons why swimming in apes was never before scientifically described, although these animals have otherwise been studied very thoroughly. We did find other well-documented cases of swimming and diving apes, but Cooper and Suryia are the only ones we were able to film. We still do not know when the ancestors of humans began to swim and dive regularly,’ said Nicole Bender. source University of the Witwatersrand
Posted on: Tue, 24 Sep 2013 11:48:49 +0000