Paleontologists have discovered a new dinosaur species, duonychus tsogtbaatari, in Mongolia’s Gobi Desert, characterised by its unique two-fingered claws. This remarkable find is especially notable because the keratin sheath protecting one of its claws remains intact, revealing that the claw exceeded the length of the bones beneath it. Measuring around 30 centimetres, this claw is the largest fully preserved of its kind.
The distinctive features of duonychus tsogtbaatari resemble a curious amalgamation of a sloth, giraffe, and the fictional character Edward Scissorhands. The dinosaur belonged to the therizinosaurs group, which contrasts with its more fearsome theropod relatives, such as Tyrannosaurus rex, as it was herbivorous or omnivorous and not an apex predator.
Standing approximately three metres tall and weighing around 260 kilograms, this dinosaur likely used its elongated, curved claws to forage for vegetation, reaching branches up to 10 centimetres in diameter. Alongside the claws, researchers also unearthed parts of its backbone, tail, hips, arms, and legs, adding to our understanding of the species.
The naming of duonychus—Greek for "two claws"—pays tribute to Mongolian paleontologist Khishigjav Tsogtbaatar. The unique structure of its claws suggests they might have also served for display or defensive purposes rather than only for feeding. According to co-author and paleontologist Darla Zelenitsky from the University of Calgary, while these creatures were not predators, their sharp claws could be utilised for self-defence.
The presence of keratin, typically not preserved in fossil records, makes this find significant, as noted by David Hone, an expert in zoology at Queen Mary University of London. The discovery sheds light on the uncertainty surrounding the relationship between keratin sheaths and underlying skeletal structures.
In terms of appearance, experts believe duonychus might have had a feathered covering, similar to other therizinosaurs, enhancing its peculiar look. Steve Brusatte, a paleontologist at the University of Edinburgh, highlighted that while most therizinosaurs are known for their large claws used to manipulate plants, duonychus stands out for its two-fingered hands. This distinct feature gives them an unusual resemblance to barbecue tongs, unlike the arms of the T. rex, which were comparatively less functional.
In summary, the discovery of duonychus tsogtbaatari not only highlights the variety of dinosaur species long before humans, but also illustrates the evolutionary path that led to such bizarre adaptations. This finding emphasizes the importance of ongoing paleontological research and the insights it continues to provide.