The discovery of a new species of ancient giant penguin, around the same height as an average human male, is reported in Nature Communications this week. Fossilized remains of the extinct penguin from approximately 60-55 million years ago, discovered in New Zealand, provide novel insights into the early evolution of penguins.
Gigantism is a known feature of penguin evolution, in which the size of ancient species exceeded that of the largest living penguins. Giant specimens are well documented from approximately 50 to 20 million years ago, but older examples in more ancestral lineages have been lacking.
Gerald Mayr and colleagues describe a new giant species named Kumimanu biceae, identified from a partial skeleton dating back to around 60-55 million years ago during the late Palaeocene of New Zealand. The find includes a femur measuring around 161 mm, from which it is estimated that the penguin weighed around 101 kg and had a body length of 1.77 m, making it one of largest penguins reported to date. K. biceae is also one of the oldest known penguin species, as only two other species are known from 62 to 58 million years ago.
Based on the evolutionary relationships of the new species, the authors conclude that the new species represents an independent origin of giant size, which took place soon after the origin of penguins and the evolutionary transition from flight to diving.