Discovered in a cave, the surprising find reveals a fast and giant bird that weighed almost as much as a polar bear.
In Cuba lives the tiniest of birds – the bee hummingbird (Mellisuga helenae), which measures in at 57 millimeters (2.24 inches) in total length, half of which is bill and tail. These wee hummers weigh a mere 1.6 grams (0.056 ounce).
But a few million years ago, birds looked decidedly different. And perhaps none more different to our beloved bee hummingbird than Pachystruthio dmanisensis, an enormous bird whose size was unknown to scientists until a surprise discovery in a Crimean cave. Although scientists formerly knew of the bird, it wasn't until this recent discovery that they calculated its size – and the thing was huge.Not only is it among the largest birds ever known, but its presence in Europe throws a curve ball to the belief that such giant birds only existed on the islands of Madagascar, New Zealand, and Australia.
The newly-discovered specimen, found in the Taurida Cave on the northern coast of the Black Sea, suggests a bird as giant as the Madagascan elephant bird or New Zealand moa. The researchers have calculated that it stood at least 3.5 meters tall and weighed about 450 kilograms.
"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 elephant bird fossil because no birds of this size have ever been reported from Europe. However, the structure of the bone unexpectedly told a different story," says lead author Dr Nikita Zelenkov from the Russian Academy of Sciences.
"We don't have enough data yet to say whether it was most closely related to ostriches or to other birds, but we estimate it weighed about 450kg. This formidable weight is nearly double the largest moa, three times the largest living bird, the common ostrich, and nearly as much as an adult polar bear."
Based on the size and shape of the femur, the scientists believe that P. dmanisensis was relatively fast. While elephant birds were too big to be speedy, the new bird's femur was long and slender, suggesting that it may have been a good runner. The bone is more akin to that of a modern ostrich or moa.
"Speed may have been essential to the bird's survival. Alongside its bones, palaeontologists found fossils of highly-specialised, massive carnivores from the Ice Age. They included giant cheetah, giant hyenas and sabre-toothed cats, which were able to prey on mammoths," write the authors.
The others fossils found nearby helped to date the big bird to 1.5 to 2 million years ago, meaning that these enormous creatures may have greeted the first hominins when they arrived in Europe. The authors suggest that it traveled to the Black Sea region via the Southern Caucasus and Turkey.
"The Taurida cave network was only discovered last summer when a new motorway was being built. Last year, mammoth remains were unearthed and there may be much more to that the site will teach us about Europe's distant past," says Zelenkov.
The research was published in the Journal of Vertebrate Paleontology.