[Article originally published on April 21, 2025]
Within the silent thickness of tropical forests, some animal practices still escape the human eye. In the north of the Republic of Congo, researchers have been tracking lowland gorillas for over a decade, revealing an unsuspected dietary habit. Through the soil they patiently excavate, these primates unveil 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.
Underground quest revealed by years of observation
In the dense forest of Nouabalé-Ndoki Park in northern Republic of Congo, researchers have closely observed the gestures of several groups of gorillas for over ten years. This long fieldwork, conducted as part of a study published in the journal Primates, identified the exact nature of what the primates were digging in the soil: an underground truffle known scientifically as Elaphomyces labyrinthinus.
These observations were made possible thanks to the involvement of Gaston Abea, a tracker from the semi-nomadic Bangombe people, whose traditional knowledge guided the scientists to this hypothesis. For over twenty years, Abea has been working with the park teams. It is through his expertise that the first clues of truffle presence were detected.
Contrary to popular belief, the gorillas were not searching for small insects but rather this rare and nutrient-rich underground fungus. The identification was made 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 practice this targeted search.
As reported by Popular Science, this practice does not appear to be widespread among the entire population. Some groups, like Buka or Kingo, show a significant frequency of this behavior. Others, such as 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.
Gorillas’ 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 interested in truffles to another group where this practice is common, gradually adapted her behavior to that of her peers.
This phenomenon of imitation and integration 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 made in bonobos, which led to the discovery of a new truffle species in 2020, Hysterangium bonobo, according to the data reported in the original study.
Finally, this discovery had a direct impact on local conservation policy. Authorities relocated a tourist construction project in the Djéké Triangle area to avoid disrupting this emerging feeding behavior, now considered a cultural element in its own right. This shift underlines how integrating local knowledge and field observations can alter our wildlife preservation strategies.
