Ancient penguins were gigantic and fearsome predators, according to a recent fossil find reported in the journal Nature Communications.
Ancient Penguins
A recently discovered 57 million-year-old fossil reveals that ancient penguins were terrifying. Standing 5 feet seven inches tall and weighing in at around 200 pounds, these waddling predators may have been comical looking, but they were nothing to joke about.
The tallest modern penguin is the emperor penguin at about four feet tall. The fossil, named Kumimanu biceae, is about a foot and a half taller. There’s some evidence that a species discovered in 2014 may have been taller at around six feet, but that height estimate may be inaccurate — being based off of just two fragments of bone. Whether Kumimanu biceae is the tallest penguin ever is up for debate, but there’s no doubt that it was a seriously imposing beast.
Outside of its significance as a new discovery, it’s also one of the oldest ancient penguin fossils ever found. The benefits of this find to the study of the modern penguin’s evolution are innumerable, and may help us discover more about the process that turned a collection of flying birds into grounded swimmers.
Although penguins can swim at speeds of around 22 miles per hour and are extremely well suited to aquatic life, their evolution has left them with stumpy legs and an inability to fly. As we discover more and more about their ancient ancestors, we may start to understand the reason behind this drastic departure from normal bird behavior.
The Evolution of Birds
Birds have mutations in their DNA at relatively expected intervals, which made them a little easier to study and predict evolutionarily when compared to other organisms. Penguins are thought to have a close indship to species like albatrosses and petrels — both birds that feed by flying over water to hunt for prey. Studies that pair these penguins closely with these other types of bird suggest that ancient ancestors of penguins may very well have flown over the water as well.
When exactly ancient penguins diverged to swim rather than fly is unclear, although studies suggest that the divergence happened around the mass extinction event roughly 66 million years ago. The first penguin fossils were found in 1859, and 50 species have been discovered since that point. The oldest known penguin, Waimanu, lived just a few million years after the extinction event, lending credence to this theory.
Scientists theorize that with the huge amount of species going extinct, the ancestors of penguins had difficulty finding prey at the surface of the water. The evolution of the ability to swim well solved this problem, allowing penguins to dive deep underneath the surface while moving quickly to catch prey that was previously out of their reach.
Comparisons of Kumimanu to Waimanu suggest that these two penguins came off the same evolutionary “branch,” meaning that this new find is set to give us some key insight into the origins of ancient penguins. As a relatively new discovery, it may be a bit before we have any new conclusive evolutionary findings, but Kumimanu may be an important part of the puzzle as we learn more and more about these birds’ ancestry.
