In 2010, a fishing net dredged up the Penghu 1 jawbone from the seafloor off Taiwan. Initially unidentified, a recent study has revealed that the jawbone belonged to a Denisovan man. The discovery was made by analyzing ancient protein fragments found in the teeth attached to the jaw. This confirmation sheds light on the evolutionary ancestry of the specimen, as proteins can survive longer than DNA. The fossil signifies the presence of Denisovans in a diverse range of environments, including a strip of land between China and Taiwan where the Denisovan man likely lived. Fishermen have often found ancient animal bones in the area, thanks to lower sea levels during the ice age past. The jawbone’s unusual journey from a fishing net to an antique shop to a museum highlights the challenges of identifying and preserving such significant archaeological finds.
“They stopped me and requested that I open it,” he recounted. “I was concerned they might be about to arrest me.” Chang shared his credentials and provided a brief human evolution lesson before being permitted to leave.
Before examining the jawbone, Welker and his team tested extraction methods on elephant and pig bones from the same seabed area to determine the presence of proteins. They successfully extracted proteins and proceeded with their analysis. The recovered amino acid sequences matched those from the Denisovan genome, revealing the individual’s gender as male.
Denisovans, discovered in 2010 from DNA sequences of a finger bone in Siberia’s Denisova Cave, were found to have interbred with early humans. Recent findings of Denisovan fossils outside Siberia suggest their widespread presence in Asia. The Xiahe mandible found in Tibet in 2019 and a rib bone in 2024 further confirmed their existence.
In Laos in 2022, a tooth resembling the Xiahe mandible was identified as Denisovan, marking their presence in Southeast Asia. However, conclusive molecular information was not obtained from this tooth. Denisovans are known for their large molars, with limited genetic data available from few fossil samples.
The well-preserved proteins in the Penghu 1 mandible found at the seabed surprised experts, suggesting the potential for more discoveries and insights into the Denisovan species in the future. Katerina Douka referred to Denisovans as a paradox due to their detailed genetic information but limited fossil records, leaving much unknown about their physical appearance. The absence of wisdom teeth in the Penghu 1 and Xiahe mandibles could indicate a different jaw structure.
In a story in Washington, DC, McRae explained that the mandibles found in Penghu do not have a chin like modern humans, indicating a flatter appearance in the front of the jawline compared to ours. The Penghu mandible is believed to be male, potentially representing the larger and more robust end of variation for this ancient species. The gender of the Denisovans remains uncertain, with the possibility that females may appear similar or quite different. The study did not involve Douka and McRae.
The unidentified ancient humans have yet to be officially classified, though some experts have suggested the name Homo juluensis to group Denisovan remains with other fossils from China, including the recently described “dragon man” skull. Chang and his team aim to examine the extensive collection of fossils stored at the National Museum of Natural Science for potential Denisovan fragments using the same proteomic methods applied to the Penghu 1 jawbone.
Chang expressed hope that further exploration of the museum’s collection could reveal previously unknown treasures. For more CNN news and newsletters, readers are encouraged to sign up for a CNN account at CNN.com.
