Researchers are flipping excited over the discovery of a giant penguin fossil that dates back 60 million years.
Teams from Te Papa, Canterbury Museum and Germany's Senckenberg Research Institute made the discovery in 2004, finding it encased in a rock near Oamaru.
The bones found suggest it was a penguin as tall as a human, measuring 1.65 metres and likely to weigh 100kg.
Te Papa curator Alan Tennyson says the size of the new penguin species is extraordinary.
"It's difficult to determine exactly what it would have looked like in life but it would have been very impressive," he said.
"[It was] as tall as many people, and a very solid, muscly animal built to withstand frequent deep dives to catch its prey.
"It would not have been the kind of bird that someone could catch alive - it would have been considerably more powerful than a person."
The species has been named the Kumimanu biceae. Kumimanu meaning "monster bird" in Māori and biceae honouring Mr Tennyson's mother, Bice Tennyson, who fostered his interest in natural history.
Mr Tennyson says the new species is a huge breakthrough. It represents an independent origin of giant size, which took place soon after the origin of penguins and the evolutionary transition from flight to diving.
"This is definitely one of the most exciting fossils that I've ever found," he says.
"At 55-60 million years old, it is nearly as old as the earliest penguin ancestors ever found, and only just after the mass extinction 66 million years ago that wiped out non-avian dinosaurs."