First Evidence To Show Elephants Recognize Themselves In Mirror
Evidence of Self-Recognition in the Magpie
Public Library of Science (PLoS)
Comparative studies suggest that at least some bird species have evolved mental skills similar to those found in humans and apes. This is indicated by feats such as tool use, episodic-like memory, and the ability to use one's own experience in predicting the behavior of conspecifics. It is, however, not yet clear whether these skills are accompanied by an understanding of the self. In apes, self-directed behavior in response to a mirror has been taken as evidence of self-recognition. We investigated mirror-induced behavior in the magpie, a songbird species from the crow family. As in apes, some individuals behaved in front of the mirror as if they were testing behavioral contingencies. When provided with a mark, magpies showed spontaneous mark-directed behavior. Our findings provide the first evidence of mirror self-recognition in a non-mammalian species. They suggest that essential components of human self-recognition have evolved independently in different vertebrate classes with a separate evolutionary history.This fascinates me because the ability to recognize oneself in a mirror has never been found in non-human animals other than apes and dolphins before. Now two separate studies have just found this ability in the largest land animal and in a noisy, obnoxious bird.
The test is to put a mark on the animal in a spot it can't see. Like the yellow spot of paint below the magpies chin. The animal knows you've done something to it, but it doesn't know what. The magpies first turned and twisted their necks trying to see what had been done to them. When that didn't work, they went to the mirror and checked themselves. Upon seeing the dot of paint in the mirroe, they tried to touch it with their beaks and feet. This was considered evidence that they used the mirror intentionally and recognized themselves in it.
This is especially important, because it had been thought that only humans, apes, and dolphins (all mammals) had this ability. Bird brains are so different from mammal brains that few scientists thought any of them might have this ability. For one thing, bird brains have no neocortex, which had been thought to be necessary for this kind of cognition.
In a different study, three female elephants at the Bronx Zoo in New York were given a huge mirror (8'x8') in their enclosure. They had time to examine it, look behind it, and get used to it. They spent a good deal of time examining the insides of their mouths in the mirror and touching spots in their mouths with their trunks. Without the mirror, elephants cannot see inside their mouths; so this was impressive to begin with. (I have no idea why they only studied female elephants with the mirror, and no males. I'm just reporting what I read. OK?)
Then, a large colored spot was painted on each animal above her eyes, and a spot of clear paint on one cheek. When they examined themselves in the mirror, they touched only the colored spots above their eyes, indicating they were seeing them in the mirror and recognizing the images as themselves. Not just responding to the human touch or the smell of the paint.
All other known species either ignore their image in a mirror or treat it like another animal. (Or they haven't been tested yet, of course.) The working hypothesis now is that this ability requires an animal with a relatively large brain and a comples social system. Elephants have the largest brains on land. Magpies and their relatives in the corvid family -- crows, jays, ravens, rooks, jackdaws, nutcrackers, and others -- have the largest brains in the bird class (aves). Both elephants and the corvids have complex social systems that require them to recognize others of their species and at least remember friend from foe.
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