The author provides overwhelming evidence that Tongan navigators and Tongan-Samoan canoe-wrights drove a generationally staged development whereby tongiaki were crossed with a Micronesian-rigged Kiribati outrigger-canoe to produce twin-hulled transitional offspring that were then crossed with similarly hybridised Kiribati-rigged hamatefua ‘outrigger-canoes’ (Fijian camakau) to produce kalia/drua.