Papua New Guinea is a country in the southwestern Pacific with some of the earliest archaeological evidence of human existence outside Africa. Largely free from Western influence and with fascinating cultural diversity, it has been of enormous interest to anthropologists and other scientists seeking to understand human cultures and evolution.
With approximately 850 domestic languages, which account for over 10 per cent of the world’s total, Papua New Guinea is the most linguistically diverse country in the world. To discover if the linguistic and cultural diversity was echoed in the genetic structure of the population, researchers studied the genomes of 381 Papuan New Guinean people from 85 different language groups within the country. A proportion of the samples examined came from a DNA archive housed at the WIMM that covers many of the Pacific island of Micronesia and Melanesia. The samples were collected in the 1980s by Prof John Clegg and Prof Sir David Weatherall, as part of their haemoglobinopathies studies. The collection is curated by Dr Kathryn Robson, also an author on this paper.
The researchers looked at more than a million genetic positions in the genome of each individual, and compared them to investigate genetic similarities and differences. The study found that groups of people speaking different languages were surprisingly genetically distinct from each other. Human evolution in Europe and Asia has been greatly influenced by the development of agriculture around 10,000 years ago. When small bands of hunter-gatherers settled into villages and started farming, they expanded and over time gave rise to more genetically homogenous (similar) societies. However, despite the independent development of agriculture in Papua New Guinea at about the same time, the same process of homogenization did not occur here. This may indicate that other historical processes in Europe and Asia, such as the later Bronze and Iron Ages, were the key events that shaped the current genetic structure of those populations.