> Regarding the PNG Vavilov zone, Jack Golson in his "History of
> Papua New Guinean Agriculture" was where I first saw it.

The Book was "A Time to Plant and a Time to Uproot: A History of
Papua New Guinean Agriculture" Edited by Donald Denoon and Catherine
Snowdon, published by the Institute for Papua New Guinean Studies,
Port Moresby. Amongst indigenous cultivars included in the
Australasian Vavilov zone are sugar cane (Saccharum sp.), sago
(Metroxylon sp.), one variety of taro (Colocasia sp.), the yams
(Dioscorea bulbifera, hispida, nummularia and pentaphila)
Australomusa bananas (Australomusa sp.), possibly coconuts (Cocos
nucifera), Pandanus nuts (Pandanus sp.) and a varity of local crops
(eg. pitpit (Setaria palmifolia)) not widely known outside of the
South East Asian region to where they were introduced from New Guinea
deep in the past, including Amaranthus sp. Rungia, Oenanathe. This
has led Ethnobotanists to suggest (before the discovery of recent
evidence at Kuk and the Solomons) "the extent to which plants
indigenous to the island (of New Guinea) are cultivated in gardens
here makes it reasonable to suggest that agriculture could have begun
in New Guinea independently of South East Asia." (p35)

This forms part of the eastern subdivision of the Indo-Malesian
Floral Region, the richest in plants useful to humankind. The very
diversity of cultivars when compared with other areas of known biotic
potential (eg. the Americas, the Middle East etc) suggests a far
greater depth of cultivation than these other regions, a depth
extending well back before the end of the last Ice Age. The fact
that we now have evidence of domesticates going back 25-28,000 years
ago, gives some length to the depths of time we are considering.

Unfortunately plant materials survive poorly in the trops and it is a
lot harder to recognise domesticated crop remains in this part of the
world (when compared to the arid-grains of the Middle East). In any
case, it seems that a complete dependence upon cultivation such as we
see in the Middle East from 8,500 BP onwards, never occurred in this
region. Cultivation was only one technology amongst a range of
hunting, fishing and gathering strategies that permitted a degree of
more permanent settlements with higher populations to occur (more
permanent in the light of shifting subsistance with a fairly long
fallow period).

The major effects of these discoveries suggest that the Europo-
Centric, and Middle-Eastern centred views for the early history of
humanity will need to be revised in a serious manner. In any case,
the priority currently given to the seed and grain crops in the
Middle East as the first cultivars may be in need of a recent
revision fairly soon. Work on extending this research is currently
proceeding.

Hope this helps

Regards

John