At a Glance
- New research demonstrates that Papua New Guineans are a sister group to East Asian populations, sharing a common ancestry from the main ‘Out of Africa’ migration event.
- The study argues that a theorized earlier migration from Africa is not needed to explain the unique genetic signals observed in the Papua New Guinean population.
- Scientists discovered that a severe population bottleneck and a slower growth rate created genetic signatures that were previously misinterpreted as contributions from an unknown ancient group.
- The distinct physical features of Papua New Guineans, which differ from those of other Asians, are likely the result of natural selection and adaptation to the tropical climate.
- Their genomes also contain significant Denisovan ancestry, which was acquired through interbreeding in Southeast Asia, adding to their complex demographic and evolutionary history.
A new study published in the journal Nature Communications challenges long-standing theories about the genetic origins of Papua New Guineans. Using advanced artificial intelligence, a team of European researchers has demonstrated that Papua New Guineans are a sister group to other East Asian populations, sharing a common ancestry from the primary migration event that populated the world outside of Africa. This finding refutes the widely held hypothesis that their ancestors originated from a separate, earlier “Out of Africa” wave.
For decades, the origins of Papua New Guineans have been a puzzle. Their distinct physical features, which sometimes resemble those of Sub-Saharan African populations, and archaeological evidence of human settlement in Oceania dating back 50,000 to 60,000 years, fueled the theory of a separate, earlier migration. The “First Out of Africa” hypothesis suggests that their ancestors took a different coastal route than the one that gave rise to European and other Asian populations. However, previous genetic studies have offered conflicting results, leaving the question unresolved.
The new research clarifies these confusing signals by analyzing the unique demographic history of the population. Scientists used high-quality genomic data to model different origin scenarios. Their results show that the genetic data, which previously seemed to indicate an ancient, separate ancestry, are better explained by a severe population bottleneck. This term refers to a sharp decline in population size that the ancestors of Papua New Guineans likely experienced after arriving in New Guinea. This event, combined with a slower population growth rate, created a distinct genetic signature.
According to lead author Dr. Mayukh Mondal, this unique history, rather than admixture with an earlier group, shaped their modern genome. While the study does not entirely rule out minor contributions from an earlier population, it concludes that such a scenario is no longer necessary to explain the data. “Perhaps adaptations to tropical climates make them look more like Sub-Saharan African groups, even though their genetics link them to other Asian populations,” Mondal stated in a press release from the Estonian Research Council. This research highlights how population-specific events can profoundly impact genetic interpretation.
References
- Estonian Research Council. (2025, July 22). New ai study clarifies the origins of papua new guineans. Phys.Org; Estonian Research Council. https://phys.org/news/2025-07-ai-papua-guineans.html
- Mondal, M., André, M., Pathak, A. K., Brucato, N., Ricaut, F.-X., Metspalu, M., & Eriksson, A. (2025). Resolving out of Africa event for Papua New Guinean population using neural network. Nature Communications, 16(1), 6345. https://doi.org/10.1038/s41467-025-61661-w
