The fossilized remains of a giant bird – three times the size of a modern ostrich and weighing twice as much as New Zealand's extinct giant moa – has been discovered unexpectedly in a cave in eastern Europe, half a world away from where all previous known giant extinct birds lived.
This is the first evidence that early Europeans lived alongside huge birds, and most likely hunted and ate them. It had been thought that gigantism in birds only developed on island landmasses such as New Zealand, Australia, and Madagascar.
The newly described species, Pachystruthio dmanisensis, was previously known to researchers through a few samples of bones but no one had calculated the size of the creature, and they were stunned when they did.
"When I first felt the weight of the bird whose thigh bone I was holding in my hand, I thought it must be a Malagasy [Madagascan] elephant bird fossil because no birds of this size have ever been reported from Europe,” explained lead author Dr Nikita Zelenkov, from the Russian Academy of Sciences, in a statement. In fact, Zelenkov and team report in the Journal of Vertebrate Paleontology, no bird of this size has ever been discovered in the Northern Hemisphere before.
The giant flightless bird would have stood around 3.5 meters (11 feet tall), and weighed about 450 kilograms (nearly 1,000 pounds), about the weight of a full grown male polar bear.
The fossil was found in the Taurida caves in Crimea, on the north coast of the Black Sea. The cave system was only discovered last summer when a new motorway was being built and has also yielded the remains of mammoths, large Ice Age carnivores like giant cheetah, giant hyenas, saber-toothed cats, and bison, which have helped date it to between 1.5 million and 1.8 million years old.
This means it may have a been a common occurrence when Homo erectus first reached Europe around 1.2 million years ago. The researchers suggest, thanks to their huge size, they may have been a valuable source of food, as well as supplying bones for tools, feathers, and eggshells.
They calculated its total size and weight using a formula based on the size of its 40-centimeter-long (~16-inch) femur, or thigh bone, one of the most commonly used bones to estimate body mass and stature due to its length.
The now extinct flightless elephant birds of Madagascar were huge. Aepyornis and Mullerornis were around 3 meters (10 feet) tall and weighed 500 kilograms (1,100 pounds), while Vorombe titan was thought to weigh up to 800 kilograms (1,760 pounds). However, their massive size hampered their speed, and though there is evidence humans lived alongside them for millennia, it’s likely easy hunting helped wipe them out in the end.
- P. dmanisensis, though also huge and flightless, had long, slim femurs, more akin to modern ostriches and extinct terror birds, suggesting it was a fast runner. This may have been essential to its survival, evading large predatory mammals. It's unknown yet whether humans helped it on its way out of existence, like we did the moa and elephant birds, or if it was a victim of the changing climate like other Ice Age giants.