Scientists have revealed through their work on fossils discovered a few years ago that penguins were over 1.7 meters tall – same height as an average human – some 59 million years ago.
The work was carried out by a team of international scientists on excavated bones that not only revealed clues about height of prehistoric penguins, but also their weight – an average 100 kilograms. The study is published in Nature Communications wherein they have shown that throughout geological history gigantism was not a rare occurrence in early penguins and probably developed as a result of the birds’ flightlessness.
Based on examination of wing and leg bones, scientists quickly came to a conclusion that the fossils in question are of a previously unknown species. The new discovery thus counts among the largest fossil penguin species, only surpassed in body size by a fossil species from Antarctica, which, however, is only known from very fragmented remains.
The giant penguin’s fossilized remnants were found in the Otago region on New Zealand’s South Island. Dating of the fossils have revealed that the bird could have lived during the Late Paleocene, i.e., about 59 to 56 million years ago suggesting that these fossils are therefore among the oldest known penguin remains, and it is remarkable that even these early forms reached such an enormous size.
Scientists demonstrate that phylogenetically the new discovery represents a rather archaic species, which is clearly differentiated from the giant penguins known to date from the geologically younger epochs of the Eocene and Oligocene.
Scientists assume that this gigantism developed as a result of the seabirds’ flightlessness. This raises the question why no penguin giants are alive today. Researchers have put forward the following hypothesis: “Giant penguins developed shortly after the mass extinction near the end of the Cretaceous, approx. 66 million years ago. It is possible that the disappearance of large marine reptiles enabled the penguins to explore new ecological niches. However, with the subsequent appearance of other large marine predators such as seals and toothed whales, the penguins faced new competition and predation – which may have led to their extinction.”