They might both be brown and flightless, but that's where similarities between two of New Zealand's most iconic birds begin and end, scientists say.
The extinct giant moa and the kiwi are often considered ancient cousins, but new research published on Wednesday show the pair have less in common than first thought.
The team led by Canadian Allan Baker from the Royal Ontario Museum, Toronto, investigated the genes of both flightless birds and discovered that despite being part of the same species group, they may have evolved to become non-flying species independently.
In fact, the moa is more closely related to the South American tinamous, a flying bird, than the kiwi, according to the study published in the journal Molecular Biology and Evolution.
Dr Baker and his team studied flightless birds or ratites, among them colourful examples such as the African ostrich, Australian emu, New Zealand kiwi and long lost giants such as the New Zealand moa.
The researchers used ancient moa DNA along with DNA from emus and other flightless birds to assemble a huge database of genetic similarities. They found that the moa was actually closely related to the winged tinamous, from a different species.
Through their work, the team have found convincing evidence the tinamous is most closely related to the wingless extinct moa, proving that each flightless bird in the ratite species lost its flying ability independently over time.
They showed that physical characters of each of the ratites evolved independently, "probably as an adaptation to a cursorial, `on-the-run' lifestyle," Dr Baker said.
