Based on a new study, New Zealand's kiwi is not linked to the emu from Australia and both flightless birds used to be able to fly. It appears that the kiwi is from the extinct elephant bird from Madagascar.
DNA study shows, the chicken-size bird is closest to the Madagascar elephant bird, which weighed about 250 kilograms or 550 pounds and grew to around three meters of 10 feet high before it was extinct around 1,000 years ago.
Researchers got DNA from the bones of flightless elephant birds and compared it with other birds. A genetic link was found with the kiwi even if they lived about 7,000 miles away with completely different body shape, size and lifestyle. It appears that the kiwi was a cousin to the emu and a sibling to the elephant bird.
Research findings contradict theories that the emu, ostrich and other flightless birds belonging to its species group called ratites evolved during the time continents broke apart around 130 million years ago.
Ratites are scattered around southern continents like in the case of South American rheas and African ostriches. Scientists used to believe that the birds have always been flightless that's why they were isolated on different landmasses at the time the continents drifted away.
"The evidence suggests flying ratite ancestors dispersed around the world right after the dinosaurs went extinct, before the mammals dramatically increased in size and became the dominant group," co-author of the study and University of Adelaide professor Alan Cooper said. The team thinks the ratites became large herbivores but when mammals got large, no bird could try becoming large herbivores again unless on an island without mammals like the Dodo.
The evolutionary history of ratites has been unclear because many of the birds independently converged on the same body plans, making its history a difficult and complicated analysis. Fossils of small kiwi ancestors were lately found and suggest that the birds may have been able to fly not very long ago. The genetics also back up the findings and confirm that kiwis used to fly when they reached New Zealand.
New Zealanders are so linked to the bird that they call themselves, their currency and fruit kiwis. The bird was named from Arabic legends which suggest that the bird was very fearsome it could seize an elephant with its talons.
