Is the Bondo Ape a Cryptid or a Specially Adapted Chimpanzee?

By: Desiree Bowie  | 
Eastern chimpanzee Alpha male Ferdinand aged 20 years resting on his back
Is this a lion-killing ape or simply an atypical eastern chimpanzee? Anup Shah / Getty Images

Nestled deep within the wilderness of the Congo Basin, the Bondo ape stands at the crossroads of legend and scientific reality. Once seen only in fleeting glimpses, this creature has become the focal point of intense curiosity and rigorous investigation.

Leading the charge into the unknown, a dedicated team of primatologists and scientists embarked on a journey to track down this elusive primate. Their quest, grounded in the meticulous application of scientific methods, aimed to unravel the truth behind the mystery ape and bridge the divide between folklore and verifiable fact.


Now, let's get to the bottom of the Bondo ape saga.

The 'Mythical' Bondo Ape

Often described as a large, bipedal primate, the Bondo ape, also known as the Bili ape, is said to resemble a cross between a gorilla and a human. This has led to speculation about its connections to cryptids like Bigfoot or the Yeti.

The term "Bondo" references a region in the Democratic Republic of Congo where many sightings have been reported. "Bili" refers to a specific area within the Bondo region known for its dense, unexplored forests.


Alpha Chimpanzee male dances in victory after scaring away the chimps from the other clan.
If you saw this guy chasing after you, you might also be inclined to classify the bipedal being as some kind of terrifying new species.
Manoj Shah / Getty Images

Bili apes have garnered a formidable reputation as "lion killers," a title that has contributed to their mystique. This reputation largely stems from local folklore and anecdotal reports suggesting that these apes had the strength and ferocity to confront and kill lions.

Such accounts have painted the Bili apes as exceptionally formidable and aggressive compared to their primate cousins, contributing to their lore.

However, scientific research and observations, such as those conducted by Hicks and Williams, have provided a more nuanced understanding of these apes. While they exhibit unique behaviors not commonly observed in other chimpanzee groups, no concrete evidence supports these sensational claims.

Rumors about these giant apes have been part of local folklore in the Congo Basin for centuries, passed down through generations of Indigenous tribes and local communities.

Interest from the Western world surged in the late 20th and early 21st centuries as explorers and cryptozoologists became intrigued by the possibility of a new primate species.

First Scientific Reports

In 1996, Karl Ammann, a Swiss photographer and conservationist, became intrigued by the possibility of uncovering a new ape species after coming across unique skulls at a Belgian museum.

This led him to the remote northern Congo, where he heard tales of the Bondo ape from local hunters. They spoke of "tree beaters" and "lion killers" — formidable apes reputed for their strength and immunity to poison arrows.

Soon after, he found a peculiar skull that combined features of both chimpanzees and gorillas. On top of this, Ammann encountered exceptionally large fecal matter and footprints that rivaled or surpassed those of gorillas in size, adding to the mystery surrounding these apes.

His decade-long exploration, marked by significant logistical efforts like constructing airstrips, attracted conservationists and researchers, including one notable primatologist who would get to the bottom of the mystery.


Searching for Mystery Apes in the Bili Forest

Shelly Williams, an independent primatologist, played a pioneering role in studying the Bili apes during her explorations in the summers of 2002 and 2003. Upon Ammann's invitation, Williams encountered and documented various groups of chimpanzees, including those she identified as the "mystery ape."

"The unique characteristics they exhibit just don't fit into the other groups of great apes," Williams told Time in 2005. "At the very least, we have a unique, isolated chimp culture that's unlike any that's been studied."


These apes were notable for their distinct physical and behavioral traits that diverged from known ape species: features such as a flatter face, a straight-across brow resembling that of gorillas, early onset graying, the absence of typical genital swelling in females and unique nesting behaviors, with some apes nesting on the ground and others in low-hanging branches.

Their vocalizations, especially the louder howls coinciding with the full moon, led Williams to hypothesize the potential discovery of a new species, subspecies or even a chimp-gorilla hybrid.

Hicks Joins the Quest

Ph.D. student Cleve Hicks brought additional insights into these enigmatic apes.

While Williams proposed groundbreaking theories on the apes' classification, Hicks focused on their behavioral patterns, noting the construction of ground nests and the use of unusually long tools for ant fishing, a behavior in which chimpanzees use sticks to extract ants from their nests, demonstrating their tool-using abilities and cognitive skills.

This marked a significant cultural divergence from known chimpanzee behaviors. His observations suggested that, genetically, these apes might not constitute a new subspecies, but their unique behaviors could signify an evolutionary departure from established chimpanzee norms.

Ammann, meanwhile, was concerned that sensational claims might undermine the credibility of their work, stressing the need for robust scientific evidence over anecdotal accounts.

Despite facing skepticism and challenges, both Williams and Hicks remained dedicated to their research. These findings spurred a flurry of interest and led to subsequent investigations.


So Is the Bili Ape Merely a Myth?

After decades of research and speculation surrounding the enigmatic apes of the DRC, a significant breakthrough was achieved in the early 2000s when it was confirmed that these mysterious primates were part of the common chimpanzee species, Pan troglodytes.

The culmination of this long-term investigation, initially sparked by observations from Williams and findings by Ammann, benefitted significantly from Hicks and his team. They employed motion-detecting cameras to capture clear images of the apes, whose unique behaviors and physical traits had puzzled scientists.


DNA analysis of collected samples finally resolved the mystery, confirming the Bili apes as common chimpanzees with distinct behavioral and ecological adaptations. This discovery highlighted the remarkable diversity within primate species and the influence of environment and culture in shaping their societies.

Over 12 years of documenting these chimpanzees in the Bili-Uéré region, Hicks and his team uncovered a host of behaviors unique to this population, including specialized tool use for insect and honey harvesting and the unusual practice of building ground nests.

These insights into their complex culture echo the early stages of human technological evolution and further our understanding of ecological adaptations.


Commonalities With Other Chimp Populations

Bili apes, despite their unique characteristics and behaviors observed in the remote forests of the DRC, share several similarities with other chimpanzee populations:

  1. Genetic makeup: Bili apes are a subgroup of the eastern chimpanzee (Pan troglodytes schweinfurthii), sharing a significant portion of their genetic makeup with other African chimpanzee populations.
  2. Social structure: Like other chimpanzees, Bili apes live in fission-fusion societies, where the size and composition of groups change over time. Members may split into smaller parties during the day for foraging and come together in the evenings to nest.
  3. Tool use: Similar to other chimpanzee communities, Bili apes have been observed using tools. While their tool use might have unique aspects due to their environment, the behavior aligns with the widespread capacity for tool use among chimpanzees.
  4. Nesting habits: Bili apes build nests for sleeping, much like other chimpanzees. Although they may exhibit a higher frequency of ground-nesting, the behavior of using vegetation to construct sleeping platforms is consistent across chimpanzee populations.
  5. Diet: Their diet includes a variety of fruits, leaves and occasionally meat, aligning with the omnivorous diet observed in other chimpanzee groups. While Bili apes might have unique dietary preferences due to their environment, the fundamental aspects of their diet are similar.
  6. Communication: Bili apes use vocalizations, gestures and facial expressions for communication, a characteristic shared with other chimpanzees. The specific calls and signals may vary, but the underlying use of complex communication is a common trait.
  7. Reproductive behaviors: Female Bili apes exhibit genital swellings during estrus, a signal of fertility also seen in other chimpanzee populations. This aspect of their reproductive biology is a key similarity.
  8. Play behavior: Juvenile Bili apes engage in play, which is essential for social bonding and learning. This behavior is universal among young chimpanzees across different populations.

This article was updated in conjunction with AI technology, then fact-checked and edited by a HowStuffWorks editor.