such as "Introduction", "Conclusion"..etc
June 4, 2008 — The dating project, in one of
the largest studies of its kind, has shown that the country was not
visited by humans over 2000 years ago, as some previous research
An international team of researchers, led by Dr Janet Wilmshurst
from Landcare Research, spent 4 years on the project which shows
conclusively that the earliest evidence for human colonisation is about
1280-1300 AD, and no earlier. They based their results on new
radiocarbon dating of Pacific rat bones and rat-gnawed seeds. Their
results do not support previous radiocarbon dating of Pacific rat bones
which implied a much earlier human contact about 200 BC.
The original old rat bones dates have been hotly debated ever since they were published in Nature
in 1996. The ages are controversial because there is no supporting
ecological or archaeological evidence for the presence of kiore or
humans until 1280-1300 AD and the reliability of the bone dating has
been questioned. This is the first time that the actual sites involved
in the original study have been re-excavated and analyzed.
Dr Wilmshurst and her team researchers re-excavated and re-dated
bones from nearly all of the previously investigated sites. All of
their new radiocarbon dates on kiore bones are no older than 1280 AD.
This is consistent with other evidence from the oldest dated
archaeological sites, Maori whakapapa, widespread forest clearance by
fire and a decline in the population of marine and land-based fauna.
“As the Pacific rat or kiore cannot swim very far, it can only have
arrived in New Zealand with people on board their canoes, either as
cargo or stowaways. Therefore, the earliest evidence of the Pacific rat
in New Zealand must indicate the arrival of people” Dr Wilmshurst said.
The dating of the rat bones was also supported by the dating of over
a hundred woody seeds, many of which had distinctive tell-tale rat bite
marks, preserved in peat and swamp sites from the North and South
“These rat-gnawed seeds provide strong additional evidence for the
arrival of rats, and therefore humans, and are an indirect way of
testing the veracity of the dates we have done on rat bones,” said Dr
Tom Higham, Deputy Director of the Oxford Radiocarbon Accelerator Unit
at Oxford University.
Rats leave rows of narrow grooves or bite marks on woody seed cases
when they gnaw open the seed, and these distinctive teeth marks can be
seen with the naked eye. “The width of the teeth marks left on the
woody seeds exactly match those of a rat's two front teeth, and cannot
be mistaken for any other seed predator. We have dated over 100
individual seeds, some rat-gnawed, others intact or bird-cracked, which
show that rat gnawed seeds only occur in both the North and South
Islands of New Zealand after about 1280 AD”, Dr Wilmshurst said.
With over 165 dates on seeds and bones from a large number of sites,
the overwhelming evidence suggests that rats and their human carriers
did not reach New Zealand until about 1280 AD.
“The earliest dates for rat and human arrival are strikingly
consistent with the oldest dates from archaeological sites, the first
large clearances of forest by fire, and declines or extinctions of
marine and land-based fauna. It now seems certain that the first Mori
settlers arrived in New Zealand sometime about 1280 AD. The consistent
picture emerging now is that settlement was much later than the old rat
bone dates led many people to believe” said Professor Atholl Anderson,
from the Australian National University.
This age has several important implications; firstly rat predation
only began after 1280 which is much shorter period than previously
implied and makes the risk to currently declining populations of
rat-sensitive species more pressing as they could be diminishing faster
than previously assumed. Secondly, colonisation did not involve a
protracted delay between initial discovery and subsequent colonisation,
an idea implicit in earlier theories. The first people arriving in New
Zealand from tropical east Polynesia initiated an immediate and rapid
“A precise date for the arrival of the rat helps us to fully
understand both the history of human settlement and the past and
present ecological impacts of kiore on native fauna and flora. It also
allows the human settlement of New Zealand to be placed more accurately
in the context of the broader settlement pattern of East Polynesia” Dr
Dr Wilmshurst and her colleagues are now turning their attention to
other islands in East Polynesia where similar controversies exist over
the timing of initial human settlement. Dates on rat-gnawed seeds and
rat bones are likely to be just as helpful in resolving controversies
on other Pacific islands where rats were also introduced
Enter the code exactly as it appears. All letters are case insensitive, there is no zero.