The Burgess Shale Formation, in the Canadian Rockies of British Columbia, is one of the most famous fossil locations in the world. A recent Palaeontology study introduces a 508 million year old (middle Cambrian) arthropod--called Yawunik kootenayi--from exceptionally preserved specimens of the new Marble Canyon locality within the Burgess Shale Formation.
Its frontal appendage--the "megacheiran great appendage"--is remarkably adorned with teeth, emphasizing an advanced predatory function. The appendage also had long hair-like flagella at the end that likely served a sensory function.
"Yawunik illustrates unique attributes in the early evolution of the most successful group of animals on Earth - the arthropods. It shows that the combination of functions on a single, frontal-most appendage was a type of strategy selected for before the grasping and sensory roles were ensured by different head limbs," said lead author and PhD candite Cédric Aria.