Vandoo,
I won't argue that gingers are Samoan (see attached pic for wild ginger), but the Helliconias came from South America and the Bird of Paradise from South Africa. The Pacific Islands have a lot of invasives and things that people have planted. The fact that you see it there now does not mean it was there 200 years ago.
Best,
F
Source: pic from
http://www.terragalleria.com/parks/n....npsa3808.html