Samples from processed tī kouka fibre found within the hull of the Papanui waka were sent off for radiocarbon dating to determine the approximate age of the waka.

Radiocarbon dating measures the ratio of carbon-14 to carbon-12 isotopes, and is a pretty reliable method of dating taoka that used carbon exchange while in use. The ratio of carbon-14 to carbon-12 is relatively equal. Once the organism dies, the carbon-14 isotopes slowly decay and revert to carbon-12.

Radiocarbon dating works out how long since the ratios were equal. The tī kouka fibre is more reliable to date than wood samples from the hull, and, gives a pretty good indication of the age of the waka by association.

Rūnanga members and archaeologists alike were pretty confident that the waka was most likely from the Kāti Māmoe occupation of Papanui Inlet, roughly around 250 years ago, although one very conservative person didn’t believe the waka would be any older than contact period – the time when the first Europeans were interacting with Māori on the peninsula, from 1810 on.

Huge surprise then, when the radiocarbon dating showed the fibre to be around 450 years old. [Read more…]