Extinct dogs' voyage from Indonesia to NZ

Wednesday, 7 October 2015

The now extinct Maori kuri dog has been found to have Indonesia cousins, new research finds.

The small pups – prized for their hunting skills and fur, but not looks – were common in New Zealand when Europeans first arrived but quickly interbred with or were ousted by newly brought canines.

Little was known about the dogs' origins until University of Otago PhD student Karen Greig attempted to piece together their DNA from ancient teeth, in a study published today in the PLOS ONE journal.

The 14 teeth from different dogs were selected from hundreds of bones found in an ancient oven in Marlborough, one of the country's first Polynesian settlements.

Greig said their final resting place indicated the dogs were cooked and eaten, likely almost 700 years ago. 'They were used as food.

'[Cooking] can increase the breakdown of DNA. So whether or not [the dogs' bones] we found were actually cooked or were leftover from processing and then the rubbish has gone back into the oven once it's finished being used - that's another possibility. The bones we sampled didn't have an obvious signs of charring or cooking.'

Temperate regions keep DNA intact far better than hot climates, so it was fairly well-preserved when Greig got her hands on it. She focussed on a specific type of DNA, mitochondrial DNA, which is passed down the maternal line and is easier to piece together. As technology developed a full nuclear genome of the kuri dog might be possible to sequence, she said.

She was able to piece the fragments of this DNA together like a jigsaw puzzle, and then compare it to the genetics of other living dogs. This showed the kuri at the Marlborough settlement were most closely related to modern-day Indonesian canines.

'At some point in time the modern Indonesia dogs and the kuri would have shared an ancestor somewhere along the way,' Greig said.

'The current thinking is that [Polynesian settlers] came down through Taiwan … But it looks like the dogs - and there's some evidence for the pigs - came a different route. So people were picking up animals and different bits and pieces along the way, so it's a little bit more complicated.'