The ancient Moa Eggshell Cave in New Zealand contains the remains of several extinct animal species lost approximately a million years ago. This finding sheds light on an understudied period of ecological history and hints at more environmental factors that could have driven the extinction of species over time.
Birds of a feather
Scientists discovered the fossils of 12 ancient bird species and four frog species in the Moa Eggshell Cave, according to a study published in Alcheringa: An Australasian Journal of Palaeontology. Of the fossils found in the cave, “about 33-50% of species went extinct during the million years before humans arrived,” said a statement about the study. These extinctions were likely “driven by relatively rapid climate shifts and cataclysmic volcanic eruptions.” Some of the notable species found include a “now-extinct ancestor of the takahe (a flightless swamphen native to New Zealand) and an ancient pigeon species closely related to Australia’s bronzewing pigeons, which were not around in the million years before humans arrived,” said The Economic Times.
The most surprising discovery was a parrot species called the Strigops insulaborealis, which is an ancient relative of the kakapo, the “only flightless parrot in the world, the heaviest parrot alive and critically endangered,” said The Economic Times. As of 2026, “there are only 235 known kakapo in existence, and all of them are on islands free of predators.” This is a “newly recognized avifauna for New Zealand, one that was replaced by the one humans encountered a million years later,” Trevor Worthy, the lead author of the study, said in the statement. “This remarkable find suggests our ancient forests were once home to a diverse group of birds that did not survive the next million years.”
Between a rock and a hard place
The findings fill in a period of New Zealand’s evolutionary history that was largely unknown. Researchers “know a lot about its really ancient past (circa 18 million years ago) and its more recent past (around 10,00 years ago), but the bit in the middle is less well understood,” said the BBC.
The fossils were found “trapped between two layers of volcanic ash,” said Earth.com. The older ash layer “fell during the Ngaroma eruption about 1.55 million years ago,” while the younger layer “came from the Kidnappers eruption right around 1 million years ago.” Having the two layers clearly defined in time gave the team “something rare: a fossil deposit with a firm age, pinned between two natural clocks.”
These discoveries also change the way researchers consider extinction. “For decades, the extinction of New Zealand’s birds was viewed primarily through the lens of human arrival 750 years ago,” Worthy said in the statement. But 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.” This “isn’t a missing chapter in New Zealand’s ancient history,” study coauthor Paul Scofield said in the statement. “It’s a missing volume.”