A 25 million-year-old penguin named Kairuku could be one of the largest that ever lived.
Scientists recently finished reconstructing the bird's skeleton from fossils found in New Zealand, the BBC reported. Their results will be published in the next edition of the Journal of Vertebrate Paleontology.
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They believe Kairuku – whose name means "diver who returns with food" in Maori – stood about 4ft 3in (1.3m) tall, had a long, sharp beak and large flippers. According to National Geographic, the tallest living penguins, Emperors, reach only 4ft (1.2m).
"It wouldn't look like any penguin that's alive today," said study co-author Daniel Ksepka of North Carolina State University, who describes Kairuku as "an elegant bird by penguin standards."
In comparison, "modern penguins are chubby little dudes," he told New Scientist.
The scientists believe Kairuku's size helped it to swim further and dive deeper than modern penguins. It lived between 24 and 27 million years ago, when most of New Zealand was underwater, they say.
"Their long beaks would have enabled these penguins to spear prey, such as fish and squid. Sharks and shark-toothed dolphins, a type of prehistoric super strong dolphin with heavily toothed jaws, probably hunted the enormous penguins, which could have snapped back with their beaks."
The team was able to get an accurate idea of the bird's height because of the completeness of the fossil remains, Ksepka explained. Remains were first discovered in a cliff at Waimate, on New Zealand's South Island, in 1977, Agence France Presse reported, and several more have been found since.
It is unclear why the giant penguins went extinct, but the researchers suspect a change in the environment is the most probable cause.
The biggest ever penguin believed to have lived was in Peru, where fossils were found suggesting that a species once stood 5ft (1.5m) tall.
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