Gibraltar’s monkeys eat mud ‘to avoid upset stomachs from tourist junk food’

Macaques have learned to eat soil to avert gut irritation caused by salty and sugary snacks, researchers believe

Troops of monkeys living on the Rock of Gibraltar have learned to eat soil in what scientists believe is an effort to settle their stomachs after all the junk food they receive - and sometimes steal - from crowds of tourists.

Researchers spotted the intentional mud eating, known as geophagy, while observing groups of Barbary macaques in the territory. Monkeys that had the most contact with tourists ate the most soil and consumption peaked in the holiday season, they found.