Jennifer Viegas, Discovery News
Oct. 30, 2006
When presented with a jumbo-sized mirror, elephants recognized their reflections and even took the opportunity to investigate the inside of their mouths and ears, according to a paper published in the current Proceedings of the National Academy of Sciences.
Such self-awareness is rare. Scientists previously believed only humans, apes and dolphins possessed self-recognition skills.
All of these animals are highly intelligent and seem to feel empathy, a quality that likely is linked to self-awareness.
"What they have in common is complex sociality that includes high levels of cooperation, altruism and large brains," coauthor Frans de Waal told Discovery News. De Waal is a psychology professor at Emory University in Atlanta and director of Living Links at the university's Yerkes Primate Center.
He added, "In literature about human children, there is speculation as to how increased self-awareness makes it possible to set the self apart from others, which in turn permits the self to take the other's perspective â a prerequisite for complex forms of empathy."
For the study, de Waal and colleagues Diana Reiss and Joshua Plotnik introduced three adult female Asian elephants â Happy, Patty and Maxine â to a large mirror placed in their exhibit at the Bronx Zoo in New York City.
According to the paper, animals typically have a social response toward the reflection they see in the mirror. They then try to inspect the mirror, for instance by looking behind it. Most animals, such as parrots, dogs and cats, show these behaviors.
The three elephants, however, had different reactions to their reflections. Each elephant played a sort of peek-a-boo by swaying their heads, trunks and bodies in and out of mirror view. They even brought food in front of the mirror and watched themselves eat.
Maxine took her trunk and stuck it in her mouth, as though she were investigating the inside of her oral cavity. She also used her trunk to pull her ear slowly forward toward the mirror.
The researchers next painted two "X" marks on the foreheads of the elephants. One mark was invisible to control for odor and tactile cues, while the other was fully visible. This "mark test" is the scientific standard for determining whether an animal recognizes itself in a mirror.
As soon as Happy saw the visible mark, she touched it with her trunk in front of the mirror. She did this 47 times. Maxine and Patty, however, ignored the marks on their foreheads.
"We believe that because elephants love to dust bathe and throw food and dirt on their backs for storage, such a relatively small mark on their head might not bother them," Plotnik told Discovery News. "Chimpanzees and humans groom themselves by picking things off their bodies, while elephants love to be covered in dirt and mud."
Lori Marino, a senior lecturer in neuroscience and behavioral biology at Emory, worked on the earlier dolphin/mirror study. She told Discovery News she was not surprised that elephants have mirror self-recognition abilities.
"Like dolphins, great apes and humans, elephant brains are large and highly convoluted and their social lives are extraordinarily complex," Marino said.
She added that many other animals possess self-awareness, a multi-faceted, complex phenomenon, which seems to manifest itself at different levels.
Since elephant self-awareness and empathy are on a similar level to that of humans, Plotnik hopes the findings will strengthen our commitment toward conservation, especially as the wild elephant population continues to plummet due to habitat loss and poaching.