An artists idea of Kumimanu and Petradyptes penguins on an ancient New Zealand beach. Kumimanu, the bigger of the two, weighed around 340 pounds and is the biggest penguin understood to science. Credit: Simone Giovanardi
Fossil bones from two newly-described penguin types, among them believed to be the biggest penguin to ever live– weighing more than 340 pounds, more than 3 times the size of the largest living penguins– have been unearthed in New Zealand.
A global group, including scientists from the University of Cambridge, reported the discovery in the Journal of Paleontology. The papers senior author, Alan Tennyson from the Museum of New Zealand Te Papa Tongarewa, found the fossils in 57 million-year-old beach boulders in North Otago, on New Zealands South Island, between 2016 and 2017.
The fossils were then exposed from within the boulders by Al Manning. They have actually been determined as being in between 59.5 and 55.5 million years of ages, marking their presence as approximately 5 to 10 million years after the end-Cretaceous termination which resulted in the extinction of non-avian dinosaurs.
An artists idea of Kumimanu and Petradyptes penguins on an ancient New Zealand beach. “Many early fossil penguins obtained enormous sizes, easily dwarfing the largest penguins alive today. Our new species, Kumimanu fordycei, is the biggest fossil penguin ever found– at around 350 pounds, it would have weighed more than Shaquille ONeal at the peak of his dominance!”
“Without Ewans field program, we would not even know that many iconic fossil species existed, so it is only right he have his own penguin namesake.”
Stonehousei honours the late Dr. Bernard Stonehouse (1926-2014), the first person to observe the complete breeding cycle of the emperor penguin, a significant turning point in penguin biology.
The team used laser scanners to produce digital models of the bones and compare them to other fossil species, flying diving birds like auks, and contemporary penguins. To approximate the size of the new types, the team measured hundreds of contemporary penguin bones and calculated a regression utilizing flipper bone dimensions to anticipate weight.
They concluded that the biggest flipper bones come from a penguin that tipped the scales at an impressive 340 pounds (154 kg). In comparison, emperor penguins, the highest and heaviest of all living penguins, generally weigh between 50 and 100 pounds (22 and 45 kg).
” Fossils offer us with proof of the history of life, and sometimes that proof is truly surprising,” said co-author Dr. Daniel Field from Cambridges Department of Earth Sciences. “Many early fossil penguins obtained massive sizes, easily overshadowing the largest penguins alive today. Our new types, Kumimanu fordycei, is the biggest fossil penguin ever discovered– at around 350 pounds, it would have weighed more than Shaquille ONeal at the peak of his dominance!”
The team called the brand-new types Kumimanu fordycei in honor of Dr. R. Ewan Fordyce, Professor Emeritus at the University of Otago. “Ewan Fordyce is a legend in our field, but also among the most generous coaches I have ever known,” said very first author Dr. Daniel Ksepka from the Bruce Museum in Greenwich, Connecticut. “Without Ewans field program, we would not even understand that many iconic fossil types existed, so it is just right he have his own penguin namesake.”
Several specimens of a second penguin species were also found, offering a comprehensive view of the skeleton. Dubbed Petradyptes stonehousei, it weighed in at 50kg, smaller sized than Kumimanu fordycei however still well above the weight of an emperor penguin. The name integrates the Greek petra for rock and dyptes for scuba diver, a play on the diving bird being protected in a boulder. Stonehousei honours the late Dr. Bernard Stonehouse (1926-2014), the first person to observe the full breeding cycle of the emperor penguin, a significant milestone in penguin biology.
These two newly-described types show that penguins got huge early in their evolutionary history, millions of years before they fine-tuned their flipper apparatus. The group observed that the 2 species kept primitive features such as more slim flipper bones and muscle accessory points that look like those of flying birds.
When asked why early penguins grew to titanic proportions, Ksepka hypothesized it made them more effective in the water. It is possible breaking the 100lb size barrier allowed the earliest penguins to spread from New Zealand to other parts of the world.”
” When we start considering these finds not as isolated bones but as parts of a whole living animal then a picture starts to form,” stated co-author Dr. Daniel Thomas from Massey University in Auckland. “Large, warm-blooded marine animals living today can dive to great depths. This raises concerns about whether Kumimanu fordycei had an ecology that penguins today dont have, by having the ability to reach deeper waters and find food that isnt accessible to living penguins.”
” Kumimanu fordycei would have been an absolutely amazing sight on the beaches of New Zealand 57 million years ago, and the mix of its sheer size and the incomplete nature of its fossil remains makes it among the most interesting fossil birds ever discovered,” said Field, who is likewise the Curator of Ornithology at Cambridges Museum of Zoology. “Hopefully future fossil discoveries will shed more light on the biology of this amazing early penguin.”
Referral: “Largest-known fossil penguin provides insight into the early development of sphenisciform body size and flipper anatomy” by Daniel T. Ksepka, Daniel J. Field, Tracy A. Heath, Walker Pett, Daniel B. Thomas, Simone Giovanardi and Alan J.D. Tennyson, 8 February 2023, Journal of Paleontology.DOI: 10.1017/ jpa.2022.88.
The research was supported in part by the National Science Foundation, UK Research and Innovation (UKRI) and the Te Papa Collection Development Fund. Daniel Field is a Fellow of Christs College, Cambridge.