In the silent depth of tropical forests, some animal practices still escape human observation. In the northern Republic of the Congo, researchers have been tracking lowland gorillas for over a decade to shed light on an unexpected eating habit. Through the soil they diligently dig through, these primates reveal a more complex relationship with taste than meets the eye. The discovery highlights a social and evolutionary dimension of gorilla feeding behavior, far beyond mere survival.
A Subterranean Quest Revealed by Years of Observation
In the dense forest of the Nouabal-Ndoki park, researchers closely observed several groups of gorillas for nearly ten years. This extensive fieldwork, published in the journal Primates, identified the exact nature of what the primates were digging in the soil: an underground truffle called Elaphomyces labyrinthinus.
These observations were made possible thanks to Gaston Abea, a tracker from the semi-nomadic Bangombe people, whose traditional knowledge guided scientists to this hypothesis. For over twenty years, he has been working with park teams. It was his expertise that initially led to the discovery of truffles.
Contrary to common beliefs, gorillas were not searching for small insects but for this rare and nutrient-rich underground mushroom. Identification was achieved through molecular classification of fragments found in the excavation sites. The park, spanning over 3,800 km², is home to around 180 western lowland gorillas, but only certain groups seem to engage in this targeted search.
As reported by Popular Science, this behavior does not appear to be widespread throughout the population. Some groups, like Buka or Kingo, show a significant frequency of this behavior. Others, like the Loya-Makassa group, rarely engage in it. This variability suggests that the origin of this behavior is not solely linked to the presence of truffles in the environment.
Feeding Behavior Influenced by the Group
Beyond simply seeking food, this truffle quest also reveals deeper social dynamics. An adult female, transferred from a group less keen on truffles to another where this practice is common, gradually adapted her behavior to that of her peers.
This imitation and integration phenomenon suggests a form of social transmission of the practice. Researchers see it as possible evidence that gorilla feeding behavior can evolve based on interactions between individuals, regardless of resource availability.
This type of immersive learning resonates with other observations in bonobos, which led to the discovery of a new truffle species in 2020, Hysterangium bonobo, as reported in the original study.
Finally, this discovery directly impacted local conservation policy. Authorities relocated a tourist construction project in the Djekok Triangle area to avoid disrupting this emerging feeding behavior, now considered a cultural element in its own right. This shift underscores how integrating local knowledge and field observations can alter our wildlife preservation strategies.
