New research from an international team of palaeontologists has found some species thought to be New Zealand natives – including kiwi and takahē – actually only arrived a few million years ago from Australia.
The new research published in scientific journal GeoBios summarised the extraordinary creatures discovered among more than 9000 specimens collected across 23 years excavating the large St Bathans fossil site in Central Otago.
The team, including Canterbury Museum senior curator of natural history Paul Scofield, had been excavating the site since 2001 and their findings suggested New Zealand’s true ancient species were animals such as kākāpō, small wrens, bats and freshwater limpets, not recent Aussie immigrants — including the kiwi, moa and takahē.
The site which was once at the bottom of a large prehistoric lake, offered the sole significant insight into New Zealand’s non-marine wildlife from 20 million years ago.
Exotic creatures identified at the site include a giant parrot that the scientists nicknamed “Squawkzilla”, two mystery mammals, flamingos, a 3-metre crocodile, a giant horned turtle and a giant bat.
Scofield, who has been involved in digs at St Bathans since 2002, said the research had prompted a rethink about the age of New Zealand’s fauna and the importance of some animals over others.
“For example, until now we thought that birds like kiwi and moa were among the oldest representatives of New Zealand fauna. We are now realising that the kākāpō, tiny New Zealand wrens and bats, and even a bizarre freshwater limpet, are the real ancient New Zealand natives.”
The research concluded that these exotic animals were wiped out by dramatic temperature drops over the last approximately 5 million years.
Study co-author Vanesa De Pietri of the University of Canterbury said the animals that lived in New Zealand 20 million years ago were very different to what we have now.
“For example, we had another giant eagle that was not related to Haast’s Eagle. We had a whole bunch of songbirds that were quite different, crocodiles and even potentially a small mammal that we’ve nicknamed the waddling mouse. We are still in the middle of our research into understanding exactly what that was.”
The latest research paper was a collaboration between Flinders University, Canterbury Museum, Te Whare Wānanga o Waitaha University of Canterbury, The University of Queensland, University of Copenhagen and University of New South Wales.
