The study focused on a fish called Gogonasus andrewsae, which lived during the Devonian period. The fossil of this fish was found in Australia and is one of the most complete examples of a fish from this time period.
The researchers used high-resolution X-ray imaging to examine the fossil in detail. This allowed them to identify the presence of a small bone in the shoulder joint of the Gogonasus. This bone is homologous to the human clavicle, which is the bone that connects the shoulder blade to the sternum.
The presence of this bone in the Gogonasus suggests that the shoulder joint evolved much earlier than previously thought. This challenges the traditional view that the human shoulder evolved as a result of the evolution of terrestrial locomotion.
Instead, the researchers suggest that the shoulder joint may have evolved as a way to provide stability to the pectoral fins of the Gogonasus as it swam. This stability would have allowed the fish to better maneuver in the water and to feed more effectively.
The study is significant because it provides new insights into the evolution of the human shoulder. It also highlights the importance of studying fossils in order to understand the evolutionary history of animals.
