Happy was the Bronx Zoo elephant that touched a painted X on her head while looking in a mirror.
The observation came from a 2006 study of mirror self-recognition in three adult female Asian elephants at the Bronx Zoo. Researchers installed an unusually large mirror, roughly 244 by 244 centimetres, and watched how the elephants responded to their reflections.
They used the mark test: a visible X was placed on one side of an elephant’s head, while a sham mark was applied elsewhere and could not be seen. Happy repeatedly touched the visible mark with her trunk, even though she could see it only through the mirror. Maxine and Patty interacted with the mirror but did not show the same mark-directed response.
The result is often described as evidence of self-awareness, but the precise interpretation is more cautious. Passing a mirror test demonstrates visual self-recognition under that experimental setup; it does not, by itself, settle every question about an animal’s consciousness. Happy’s result nevertheless made her one of the best-known elephants in cognition research.