It’s always a good idea to wash produce before eating it. It’s a simple way to help prevent the spread of germs, in addition to removing dust, dirt, and pesticide residue. As humans, we know this is good practice, but what about animals?
Although this behavior is certainly not widespread in the animal kingdom, researchers have discovered that some creatures can distinguish between clean and dirty foods. In one highly unusual incident, a group of European wild boar at Basel Zoo in Switzerland were observed transporting dirty apples to a nearby stream, where they gently washed them using their snouts. Animal behavior experts were amazed to see that despite being hungry, the boar were willing to delay gratification in order to clean their sand-covered apple slices. Notably, when the wild boar were given clean apples, they did not repeat the washing procedure and instead ate them immediately.
One explanation is that removing sand and dirt from their food helps prevent damage to the boars’ teeth and aids in digestion. However, many questions remain. The researchers are unsure whether this behavior was learned individually or as a group but noted that it was practiced by all of the zoo’s adult and juvenile wild boar. They observed that while the piglets in the group did not engage in washing their food, they still moved it around with their snouts, seemingly cleaning off any sand before eating.
Not so dirty after all:
- *The unusual behavior of carrying soiled apples to a nearby stream for washing was first observed by zoo employees by chance, following the arrival of several new wild boar to Basel Zoo in 2013.
- *Researchers from University College London conducted follow-up experiments, confirming that the behavior was not a coincidence.
- *Their findings about the Basel Zoo boars were published in the journal Animal Cognition in July 2015.