http://www.wired.com/wiredscience/2009/10/pigs-and-mirrors/
Quote
In just five hours, an average farm pig can learn how to interpret an image in the mirror and use it to find hidden food.
Scientists consider the ability to use a mirror a sign of complex cognitive processing and an indication of a certain level of awareness. In addition to humans and some primates, dolphins, elephants, magpies and a famous African grey parrot named Alex have all been known to retrieve objects or remove marks on their body using a mirror. Now it looks like pigs should be added to the list of clever critters that can master a mirror: After spending five hours with a mirror in their pen, seven out of eight pigs could use the reflection to find a hidden bowl of grub.
...continued (http://www.wired.com/wiredscience/2009/10/pigs-and-mirrors/)