A newly discovered fossil site reveals that New Zealand’s wildlife was being transformed by extreme natural forces millions of years before humans set foot on the islands.
Credit: Courtesy Paul Scofield (Canterbury Museum), generated by AI
Deep within a cave on New Zealand’s North Island, scientists have uncovered a long-lost record of life from a million years ago.
In a cave system near Waitomo on Aotearoa’s North Island, scientists have uncovered a packed deposit of ancient bones that captures New Zealand at a moment the fossil record rarely preserves. The find is the first time researchers have recovered such a large set of fossils from around one million years ago, and it includes a surprise: an early relative of the kākāpō, the famously hefty parrot that today cannot fly.
The site holds remains from 12 bird species and four frog species, giving researchers an unusually detailed sample of the wildlife that once lived in the region. Because caves can act like natural storage vaults, preserving fragile bones that would normally disappear in open landscapes, discoveries like this can reveal entire communities rather than isolated specimens.
The research, published in Alcheringa: An Australasian Journal of Palaeontology, argues that New Zealand’s ecosystems were being repeatedly reshaped long before humans arrived. Instead of a stable cast of species enduring unchanged for millennia, the evidence points to dramatic turnovers linked to severe climate shifts and major volcanic events, with extinctions followed by replacements as habitats transformed.
Lead author Flinders University Associate Professor Trevor Worthy says the study changes the baseline for understanding what “natural” once looked like in New Zealand.
“This is a newly recognized avifauna for New Zealand, one that was replaced by the one humans encountered a million years later,” says Associate Professor Worthy, from the College of Science and Engineering at Flinders University.
“This remarkable find suggests our ancient forests were once home to a diverse group of birds that did not survive the next million years.”
Fossils and Extinctions Before Humans
The fossils were examined by palaeontologists from Flinders University and Canterbury Museum, working alongside volcanologists Joel Baker from the University of Auckland and Simon Barker of Victoria University of Wellington.
Their analysis suggests that roughly 33–50% of species disappeared during the million years leading up to human settlement in Aotearoa New Zealand.
According to co-author Dr. Paul Scofield, Senior Curator of Natural History at Canterbury Museum, these losses were linked to rapid environmental change and large-scale volcanic events.
“From our excavations at St Bathans in Central Otago over many years, we have a snapshot of life in Aotearoa between 20 and 16 million years ago. These new findings cast light on the 15 million-year period from then to 1 million years ago, which is largely absent from New Zealand’s fossil record,” says Dr. Scofield.
“This wasn’t a missing chapter in New Zealand’s ancient history, it was a missing volume.”
Ancient Relatives of Iconic Birds
Among the most notable discoveries is a previously unknown parrot species, Strigops insulaborealis, which belongs to the same lineage as the modern kākāpō. While today’s kākāpō is a large, ground-dwelling bird that cannot fly, its ancient relative may not have shared that limitation.
Studies of the fossil bones indicate that the extinct parrot had weaker legs than the modern kākāpō, suggesting it was less adapted for climbing. Scientists say additional research will be needed to determine whether it was capable of flight.
The cave also preserved the remains of an extinct ancestor of the takahē, offering new insight into the evolutionary history of one of New Zealand’s most recognisable birds. In addition, researchers identified a now-lost pigeon species closely related to Australian bronzewing pigeons.
“The shifting forest and shrubland habitats forced a reset of the bird populations,” adds Dr. Scofield.
“We believe this was a major driver for the evolutionary diversification of birds and other fauna in the North Island.”
Among the most notable discoveries is a previously unknown parrot species, Strigops insulaborealis, which belongs to the same lineage as the modern kākāpō. While today’s kākāpō is a large, ground-dwelling bird that cannot fly, its ancient relative may not have shared that limitation.
Studies of the fossil bones indicate that the extinct parrot had weaker legs than the modern kākāpō, suggesting it was less adapted for climbing. Scientists say additional research will be needed to determine whether it was capable of flight.
The cave also preserved the remains of an extinct ancestor of the takahē, offering new insight into the evolutionary history of one of New Zealand’s most recognisable birds. In addition, researchers identified a now-lost pigeon species closely related to Australian bronzewing pigeons.
“The shifting forest and shrubland habitats forced a reset of the bird populations,” adds Dr. Scofield.
“We believe this was a major driver for the evolutionary diversification of birds and other fauna in the North Island.”
Dating a Million-Year-Old Cave
The fossils could be accurately dated as they were between two layers of volcanic ash preserved in the cave. One layer was from an eruption 1.55 million years ago, while the other was from a massive eruption 1 million years ago.
The more recent eruption would have blanketed much of the North Island in meters of ash. Most of it would have been washed away, but some would have been preserved in caves. The older layer found at this fossil site proves it is the oldest-known cave in the North Island.
Associate Professor Worthy says the fossils “provide a critical, missing baseline for New Zealand’s natural history.”
“For decades, the extinction of New Zealand’s birds was viewed primarily through the lens of human arrival 750 years ago. This study proves that natural forces like super-volcanoes and dramatic climate shifts were already sculpting the unique identity of our wildlife over a million years ago.”
The Life of Earth
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