PARIS, Dec 9 — We know that dogs and cats don’t recognise themselves in the mirror, but what about Adélie penguins? Researchers in India have put these Antarctic birds through the famous mirror test to determine whether they understand that they are looking at themselves when they see their reflection. The conclusions of their study are the subject of debate.
The study was recently published via the BioRxiv preprint repository for biological sciences. In it, a team of researchers, led by Anindya Sinha of the National Institute of Advanced Studies in India and Prabir Ghosh Dastidar of India’s Ministry of Earth Sciences, explain how they put wild Adélie penguins (Pygoscelis adeliae) living on Svenner Island in Antarctica through the mirror test.
This experiment was originally devised in the 1970s by the American psychologist Gordon Gallup to determine the ability of a being to recognise its own reflection in a mirror. Scientists make a spot on the animal’s forehead — a part of the body that can only be seen through its own reflection — and place it in front of a mirror. If the animal tries to touch or remove the spot, it knows that it is seeing its reflection in the mirror. This theoretically reflects an awareness of themselves.
Only a few animals have passed this test, including Asian elephants, dolphins and some great apes. And Adélie penguins are among them, according to the study by Anindya Sinha and colleagues. To reach this conclusion, the researchers tested the birds’ reactions to their reflection in three different scenarios.
The first involved placing three Adélie penguins in a cardboard box with two mirrors. The scientists noticed that the birds spent a lot of time inspecting their reflection, leading them to say that they were engaged in an “exploration of their self-images.” In particular, they had fun looking at themselves in the mirror while they moved their heads or flippers.
Another group of penguins was subjected to a similar test in the second scenario, but this time a paper disc was attached to the mirror so that they could not see their heads and upper bodies in the mirror. The result: the birds seemed much more agitated than in the first experiment. The researchers said that they even started pecking at the paper sticker to try to remove it. “There could also be alternative explanations, such as a discomfort generated by the failure to see the eyes of the image, any penguin image, not necessarily their own,” Anindya Sinha told New Scientist magazine.
A test of disputed reliability
To determine whether or not Antarctica’s flagship birds are self-aware, the research team put a few of them through a final test. They put coloured bibs around the necks of five of them to see how they reacted. To their surprise, the scientists noticed that the penguins continued to examine their reflection without attempting to touch or remove the bibs, as if they weren’t aware of their presence on their bodies. Yet, recognising a foreign object or mark on an animal’s body is an essential criterion of the mirror test.
Despite this, the researchers say that Adélie penguins possess, albeit to a lesser degree, some sense of self-identity and subjective self-awareness. “We speculate that it is entirely possible that similar phenomena may exist in penguin species, including Adélie penguins, with their complex social lives within communal rookeries,” the scientists write in their paper.
This interpretation is disputed by some specialists, including Frans de Waal, a Dutch-American primatologist who teaches at Emory University in Georgia. “When they gave the penguins bibs in front of the mirror, the birds did not direct their attention specifically to the bibs, which suggests they don’t connect their mirror image with themselves,” the specialist told New Scientist.
Experts are increasingly skeptical about the scientific relevance of the mirror test to determine whether animals recognise their reflection. Many believe that this experiment does not prove whether or not they are self-aware. Especially since some human infants fail the mirror test, as North American researchers pointed out in a 2010 study published in the Journal of Cross-Cultural Psychology.
For Pete Roma, an American researcher specialising in psychology, self-awareness is similar to gravity. “We can’t touch it directly, so if we want to measure it, scientists must develop valid techniques to directly observe its effects. Currently, mirror mark tests are the best-known and most accepted method, but the absence of an effect does not necessarily mean the absence of the thing we’re trying to measure,” he told Scientific American in 2010. And so, much mystery remains as to the ability of wild animals to recognise themselves in a mirror. — ETX Studio
