When ancient humans first arrived in Europe they may have lived alongside some of the biggest birds to walk the Earth—11-foot-tall, 1,000-pound ostrich-like creatures.
Until recently, gigantism in birds was thought to be confined to the distant lands of Madagascar, New Zealand and Australia. The biggest known species are elephant birds, which lived towards the end of the Quaternary period (about 2.5 million to 11,700 years ago). These creatures were estimated to have had a body mass of up to 1,500 pounds. In comparison, the common ostrich weighs in at around 300 pounds.
"Fossil birds of such an impressively giant size have never been documented from Europe or the Northern Hemisphere in general," scientists from the Russian Academy of Sciences noted in a paper published in the Journal of Vertebrate Palaeontology.
However, excavations at the Taurida Cave in the Crimean Peninsula led to the discovery of an enormous species of bird.
The species is not new—it had previously been identified from fossils found at sites in Eastern Europe before. But until now it was not clear when it lived or whether early humans would have had contact with it.
Scientists say the bird, named Pachystruthio dmanisensis, was likely a flightless creature. Its femur, which was long and thin, suggests it was a fast runner. After analyzing the bone, the team say it probably reached around 11 foot in height and weighed in at almost 1,000 pounds—equivalent to a polar bear.
Pachystruthio was found alongside ancient bison bones and other fossils, allowing scientists to date it to between 1.5 and two million years ago. This is comparable with the age of a nearby archaeological site thought to be the earliest evidence of hominins outside of Africa.

Artist impression of the giant, extinct bird found in a cave in Crimea. Andrey Atuchin
As a result, the researchers believe these enormous birds would have been part of the landscape by the time our ancestors arrived. "These large birds might have been a source of meat, bones, feathers, and eggshell for early hominin populations," the scientists wrote.
Nikita Zelenkov, lead author of the study, told Newsweek these first people probably did not hunt the creature: We do not have yet evidence of any interactions with early humans, but any kind of them must have existed. I do not think that it was a dangerous animal, and it's running ability likely prevented from being a prey of early people."
Other animals living in the region at the same time as Pachystruthio include giant cheetah, giant hyenas and saber-toothed cats. Its ability to run was likely key to its survival, the researchers say.
They currently do not know which bird species Pachystruthio is most closely related to. Excavations are continuing at the cave site it was discovered in, and Zelenkov says they hope to unearth more bones to better understand the species.