Paleontologists in New Zealand have uncovered a nearly complete skeleton of a giant-sized penguin that swam the oceans about 27 million years ago (Oligocene period).
New Zealand is a key area for understanding the ancient history of penguins.
Fossils found there range in age from Paleocene up to Pleistocene, constituting a period that spans more than 60 million years.
The country’s fossil record includes many genera and species of ‘giant’ penguins (i.e., larger than living penguins), such as Kairuku, Pachydyptes, Palaeeudyptes and Kumimanu.
The ancient giants differed from their living descendants in the length of their front limbs and elongated beaks, perhaps suggesting differences in ecological roles when compared with living species.
The new fossil, which belongs to the genus Kairuku, was found in an Oligocene silty mudstone in Kawhia Harbour, New Zealand’s North Island.
“The Kawhia giant penguin is mostly complete and largely articulated in life position, which helps a great deal with reconstructing the relatively long and slender body,” said Simone Giovanardi, a Ph.D. student at Massey University Albany.
The forelimbs of the new penguin are almost identical in size when compared with Kairuku grebneffi, a similarly-aged giant penguin from the South Island of New Zealand.
However, its hindlimbs are significantly longer, exceeding in length all previously described specimens of the Kairuku genus.
“Moreover, the specimen presents a mixture of characters that show a transitional state between the ancestral body plan found in other Eocene-Oligocene giant penguins and the body plan found in Kairuku, providing insight into the diversification of giant penguins,” Giovanardi and colleagues said.
The scientists reported the discovery October 9, 2019 at the 79th Annual Meeting of the Society of Vertebrate Paleontology in Brisbane, Australia.
Simone Giovanardi et al. A New Sphenisciform Fossil from the North Island of New Zealand Further Resolves the Bauplan of Extinct Giant Penguins. SVP 2019