It might not be your first choice for a meal, but many mammals appear to find earth an appetizing addition to their diet
Known as geophagy, scientists still aren’t sure what causes the surprisingly common urge to eat soil or clay
To understand soil eating and its causes, researchers reviewed every documented case of soil eating in monkeys and apes
They identified cases of soil eating in 136 species – over half of all monkeys and apes found around the globe – suggesting the behavior is more common than previously thought
Evidence from the 287 articles reviewed also suggests that geophagy is a form of self-medication
Geophagy may provide protection against disease-causing pathogens and supplement essential nutrients
Although more research is needed, the work lays a foundation for future investigations into the causes and health impacts of geophagy
The findings could also reveal new ways to promote the health of both wild and captive primate populations
Pebsworth PA, et al. Geophagy among non-human primates: A systematic review of current knowledge and suggestions for future directions. American Journal of Physical Anthropology (2018)