Mr Clarke used molecular genetic techniques to determine the origins of the sweet potato (kumara) and the bottle gourd in Oceania. Both are thought to have been introduced into Oceania by Polynesian voyagers who collected them from South America about 1,000 years ago (the word kumara is used by indigenous South Americans). Using new and improved DNA techniques, Mr Clarke analysed several hundred varieties of sweet potato and about 40 varieties of bottle gourd. The results are consistent with a pre-European introduction of these crops into Polynesia from South America, and have revealed something about their dispersal patterns within Polynesia, including New Zealand.

Mr Clarke used molecular genetic techniques to determine the origins of the sweet potato (kumara) and the bottle gourd in Oceania. Both are thought to have been introduced into Oceania by Polynesian voyagers who collected them from South America about 1,000 years ago (the word kumara is used by indigenous South Americans). Using new and improved DNA techniques, Mr Clarke analysed several hundred varieties of sweet potato and about 40 varieties of bottle gourd. The results are consistent with a pre-European introduction of these crops into Polynesia from South America, and have revealed something about their dispersal patterns within Polynesia, including New Zealand.

Mr Clarke used molecular genetic techniques to determine the origins of the sweet potato (kumara) and the bottle gourd in Oceania. Both are thought to have been introduced into Oceania by Polynesian voyagers who collected them from South America about 1,000 years ago (the word kumara is used by indigenous South Americans). Using new and improved DNA techniques, Mr Clarke analysed several hundred varieties of sweet potato and about 40 varieties of bottle gourd. The results are consistent with a pre-European introduction of these crops into Polynesia from South America, and have revealed something about their dispersal patterns within Polynesia, including New Zealand.