Its name is Kairuku (“diver who returns with food,” in Maori) and lived 25 million years ago in New Zealand. It was the tallest among five species of penguins in the region, with a height of more than 1.2 meters (4 feet 2 inches). Researchers have reconstructed it from two different fossils collected in 1977, as described in the Journal of Vertebrate Paleontology.
“Kairuku was an elegant bird by penguin standards, with a slender body and long flippers, but short, thick legs and feet,” says Dr Daniel Ksepka, researcher at the North Carolina State University and co-author of the study. “If we had done a reconstruction by extrapolating from the length of its flippers, it would have stood over 6 feet tall [around 1.8 meters]. In reality, Kairuku was around 4-feet-2 inches tall or so.”
This finding may help palaeontologists study giant penguins living in the Oligocene period (about 34 million to 23 million years ago). It is believed that New Zealand was “great for penguins in terms of both food and safety”, according to Ksepka. “Most of New Zealand was underwater at that time, leaving isolated, rocky land masses that kept the penguins safe from potential predators and provided them with a plentiful food supply.”
It seems that New Zealand species, however, were not the biggest ones. In 2007 and 2010, scientists discovered in Peru two penguin species of about 1.5 meters (5 feet) tall, which lived 36 million years ago.
Ksepka, D.T., R.E. Fordyce, T. Ando, & C.M. Jones (2012). New Fossil Penguins (Aves, Sphenisciformes) from the Oligocene of New Zealand Reveal the Skeletal Plan of Stem Penguins Journal of Vertebrate Paleontology