A massive thigh bone found in a Crimean cave belongs to an extinct flightless bird more than 10 times the weight of an emu.
Weighing in at nearly half a tonne, it is one of the largest birds to have graced the planet, and the first to be found in the northern hemisphere, according to a description published in the Journal of Vertebrate Paleontology.
“No birds of this size have ever been reported from Europe,” says Nikita Zelenkov, from the Russian Academy of Sciences, who led the study.
The thigh bone, from the prehistoric species Pachystruthio dmanisensis, was excavated from the recently discovered Taurida cave on the Crimean Peninsula, which juts into the Black Sea from the north.
Based on the size of the 40-centimetre-long bone, Zelenkov and his team calculated that its owner weighed approximately 450 kilograms and stood 3.5 metres tall.
Monstrous birds were not uncommon in prehistoric times. The largest species of New Zealand’s extinct Moa stood 3.6 metres tall and, at 230 kilograms, weighed about half what Pachystruthio did.
The elephant birds of Madagascar, meanwhile, weighed in at a whopping 730 kilograms, making them the largest to have ever lived.
Australia, too, had its own ancient behemoths. Stirton’s thunderbird stood three metres tall and weighed half a tonne.
Despite its heft, the slim dimensions of the thigh bone indicate Pachystruthio was a fleet-footed creature.
That’s probably just as well. Alongside the thigh bone, palaeontologists also unearthed fossils from a host of fearsome predators, including giant cheetahs, giant hyenas and sabre-toothed cats.
Fossilised bones from bison at the site indicate the remains are between 1.5 and 1.8 million years old.
The range of animals found is not unlike the discoveries at the Dminisi site east of the Black Sea, 55 kilometres southwest of Georgia’s capital, Tbilisi.
But that site, dating back to 1.7-1.8 million years ago, is significant for other reasons. Early human remains from Dmanisi are the earliest evidence of our ancestors’ outside of Africa
It’s quite possible that the Dmanisi hominins or later Homo species arriving in the region from Africa could have shared the landscape with the feathered giant.