Genetics and the Origins of the Polynesians
Abstract
Anatomically modern humans first arose in Africa. They rapidly spread out across the world with their earliest dispersers reaching as far as Australasia 40 000–60 000 years before present (ybp). Migration routes have been traced pretty thoroughly by molecular methods, but many controversies still remain. Recently debate has been focused on the relative importance of competing alternate pathways and the extent of interaction with other ancient peoples: Neanderthals and Denisovans. The origin of the Polynesian people who settled in Remote Oceania is a particularly long-standing mystery. Surveys of genetic variation in these populations have helped to distinguish between competing theories arising from anthropology and linguistics. The genetic data show how maternal and paternal lineages combined approximately 3000 ybp giving rise to a new people who spoke Austronesian languages and developed a sophisticated technology for oceanic voyaging.
Key Concepts:
Anatomically modern humans came from Africa and dispersed widely in a relatively short time.
Dispersal patterns plus the timing and extent of gene flow from ancient people have all become controversial topics in recent years.
Pacific Island populations must be described in terms of culture and ancestry as well as their geographic location.
Genetic surveys are powerful tools for testing hypotheses about the migration histories of human populations.
Molecular markers can inform both pattern (origins and pathways) and process (hybridisation, gene flow, founder effects, etc.) in human evolution.
Maternal and paternal markers reveal different ancestors for Pacific people: Austronesian and Papuan, respectively.
Almost all preceding ‘Fast Train’ and ‘Slow Boat’ type models are captured as elements of an extended ‘Synthetic Total Evidence Model’.
Genetic studies of Pacific plants and animals support the emergent view from human genes, language and culture.
In any and all causal explanations of human history, known process elements must fully account for observed patterns.
