How it began
At Kuk Swamp in the Western Highlands of Papua New Guinea, Tim Denham and colleagues found banana phytoliths, microscopic silica bodies from the plant, throughout sediments of the last 10,000 years. High proportions in disturbed ground before about 6,950 years ago only hinted at planting. From 6,950 to 6,440 years ago bananas made up a large share of the plants in a managed grassland, which the authors read as proof of deliberate planting. The phytoliths included Musa acuminata subspecies banksii.
Before it existed
The 2003 study notes that New Guinea had been seen as a place that received its crops from Southeast Asia. The authors report that the Kuk evidence matched earlier genetic work indicating that Eumusa bananas were domesticated in Melanesia, and that domesticated plants from Southeast Asia reached New Guinea only after about 3,500 years ago, following Austronesian expansion.
How it works
Bananas at Kuk were grown alongside taro on mounds raised at the edge of the wetland, which kept the roots out of saturated soil. Researchers identify the plants from the shape of phytoliths, including those from seeds. Seed phytoliths with distinct ridging separate the Eumusa section, which includes the ancestors of edible bananas, from other wild bananas growing in the highlands.
What lasted
Denham and colleagues concluded that New Guinea was a primary center of plant domestication and that bananas and taro were domesticated there independently. UNESCO lists banana with taro and yam among the crops behind its judgment that Kuk shows independent agricultural development.
Where it stands today
The Kuk site, where the evidence was found, has been a UNESCO World Heritage property since 2008. UNESCO describes the 116 hectare swamp as a landscape of wetland reclamation worked almost continuously for 7,000 and possibly 10,000 years, and reports that present-day farming there remains low-key.
