By: ANDREW BRIDGES Washington. New test results sug gest elephants are able to distinguish themselves from others, a trait that has so far only been shown in humans, chimpanzees, and to a limited extent, dolphins. A 34-year-old female Asian elephant in the Bronx Zoo named Happy showed researchers that pachyderms can recognise themselves in a mirror — complex behaviour observed in only a few other species. That self-recognition may underlie the social complexity seen in elephants, and could be linked to the empathy and altruism that the big-brained animals have been known to display, said researcher Diana Reiss of the Wildlife Conservation Society, which manages the Bronx Zoo. In a 2005 experiment, Happy faced her reflection in an mirror and repeatedly used her trunk to touch an “X” painted above her eye. The elephant could not have seen the mark except in her reflection. Furthermore, Happy ignored a similar mark, made on the opposite side of her head in paint of an identical smell and texture, that was invisible unless seen under black light. “It seems to verify for us she definitely recognised herself in the mirror,” said Joshua Plotnik, one of the researchers behind the study. Details appear this week on the website of the proceedings of the National Academy of Sciences. Still, two other zoo elephants, Maxine and Patty, failed to touch either the visible or invisible “X” marks on their heads in two runs of the experiment. But all three adult female elephants at the zoo behaved while in front of the jumbo mirror in ways that suggested they recognised themselves, said Plotnik, a graduate student at Emory University in Atlanta. Maxine, for instance, used the tip of her trunk to probe the inside of her mouth while facing the mirror. She also used her trunk to slowly pull one ear toward the mirror, as if she were using the reflection to investigate herself.
The researchers reported not seeing that type of behaviour at any other time. “Doing things in front of the mirror: that spoke volumes to me that they were definitely recognising themselves,” said Janine Brown, a research physiologist and elephant expert at the Smithsonian National Zoological Park in Washington. She was not connected with the study but expressed interest in conducting follow-up research.
Gordon Gallup, the psychologist who devised the mark test in 1970 for use on chimps, called the results “very strong and very compelling”.
But he said additional studies on both elephants and dolphins were needed.
“They really need to be replicated in order to be able to say with any assurance that dolphins and elephants indeed as species are capable of recognising themselves. Replication is the cornerstone of science,” said Gallup, a professor at the State University of New York at Albany, who provided advice to the researchers.
The three Bronx Zoo elephants did not display any social behaviour in front of the mirror, suggesting that each recognised the reflected image as itself and not another elephant.
Many other animals mistake their mirror reflections for other creatures. That divergent species such as elephants and dolphins should share the ability to recognise themselves as distinct from others suggests the characteristic evolved independently, according to the study.
The researchers reported not seeing that type of behaviour at any other time. “Doing things in front of the mirror: that spoke volumes to me that they were definitely recognising themselves,” said Janine Brown, a research physiologist and elephant expert at the Smithsonian National Zoological Park in Washington. She was not connected with the study but expressed interest in conducting follow-up research.
Gordon Gallup, the psychologist who devised the mark test in 1970 for use on chimps, called the results “very strong and very compelling”.
But he said additional studies on both elephants and dolphins were needed.
“They really need to be replicated in order to be able to say with any assurance that dolphins and elephants indeed as species are capable of recognising themselves. Replication is the cornerstone of science,” said Gallup, a professor at the State University of New York at Albany, who provided advice to the researchers.
The three Bronx Zoo elephants did not display any social behaviour in front of the mirror, suggesting that each recognised the reflected image as itself and not another elephant.
Many other animals mistake their mirror reflections for other creatures. That divergent species such as elephants and dolphins should share the ability to recognise themselves as distinct from others suggests the characteristic evolved independently, according to the study.
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