In a finding likely to be a bitter blow for many New Zealanders, researchers have found the kiwi is probably descended from an ancestor that flew in from Australia.
Palaeontologist Trevor Worthy of Adelaide's Flinders University said fossilised remains suggested the flightless bird did not evolve from the extinct giant moa, as has long been assumed.
Instead, he said an ancestor of the kiwi dating back 20 million years discovered in the South Island was more closely related to another giant flightless bird, the emu, which is still common in Australia.
Dr Worthy, an expatriate New Zealander, said it appeared the fossilised South Island bird and the emu evolved from a common ancestor, which originated in Australia but also spread to New Zealand.
"If, as the DNA suggests, the kiwi is related to the emu, then both shared a common ancestor that could fly," he said. "It means they were little and volant [able to fly] and that they flew to New Zealand."
Dr Worthy said it was not uncommon for birds to "jump" from Australia to New Zealand, citing the mallard duck, the little banded dotterel and the cattle egret as three species that often flew back and forth.
He said the research, published by the Society of Avian Paleontology and Evolution, was not conclusive.
"We need to find wing bones to put the theory beyond all doubt," he said.
New Zealanders have long complained about Australians appropriating everything from champion race horse Phar Lap to the pavlova, and any claim to the kiwi is likely to add fuel to the fire.
But David Lawrie, president of the Ornithological Society of New Zealand, which aims to foster the study, knowledge and enjoyment of birds, said that while he was not an expert, the suggestion did not surprise him.
"The general public might get a bit excited, but I think those in the birding community would be expecting it and I don't think it would be unexpected at all."
Is the kiwi an Aussie?
* A palaeontologist from an Australian university says fossilised remains suggest the kiwi did not evolve from the giant moa.
* Instead, he says, an ancestor of the kiwi was more closely related to the emu, which is still common in Australia.
* The kiwi's ancestor and the emu are both likely to have evolved from a common ancestor which originated in Australia but also spread to New Zealand, it is suggested.