Joshua Plotnik, a behavioral ecologist at Mahidol University in Kanchanaburi, Thailand, and primatologist Frans de Waal, director of Emory University's Living Links Center, have shown through a controlled study what those who work with elephants have always believed: The animals, in this case captive Asian elephants (Elephas maximus), offer something akin to humans' sympathetic concern when observing distress in another, including their relatives and friends.

The scientists studied 26 elephants of varying ages at the Elephant Nature Park in the Mae Tang district of Chiang Mai Province, Thailand. (Adult male elephants were excluded for safety reasons.)

It would be unethical to set up stressful situations, so they instead waited patiently for such moments to occur naturally.

A stress-inducing situation