A new study of an ancient bony fish has forced scientists to rethink how sharks evolved. The study, published in the journal Nature, found that the fish, called _Andreolepis hedei_, had a number of features that were previously thought to be unique to sharks. These features include a cartilaginous skeleton, a dorsal fin, and a tailfin with a lower lobe that is longer than the upper lobe.

The discovery of _Andreolepis hedei_ suggests that the features that were thought to be unique to sharks may have evolved independently in both sharks and bony fish. This would mean that sharks and bony fish are not as closely related as previously thought.

The study also has implications for our understanding of the evolution of vertebrates. The discovery of _Andreolepis hedei_ suggests that the cartilaginous skeleton may have evolved earlier than previously thought. This would mean that the cartilaginous skeleton may be the ancestral condition for vertebrates, and that the bony skeleton evolved later.

The study of _Andreolepis hedei_ is a reminder that our understanding of the evolution of life is constantly changing. As new fossils are discovered, we are learning more about the diversity of life in the past and how different groups of organisms are related to each other.

Here is a summary of the key findings of the study:

* _Andreolepis hedei_ is an ancient bony fish that lived about 380 million years ago.

* _Andreolepis hedei_ had a number of features that were previously thought to be unique to sharks, including a cartilaginous skeleton, a dorsal fin, and a tailfin with a lower lobe that is longer than the upper lobe.

* The discovery of _Andreolepis hedei_ suggests that the features that were thought to be unique to sharks may have evolved independently in both sharks and bony fish.

* This would mean that sharks and bony fish are not as closely related as previously thought.

* The study also has implications for our understanding of the evolution of vertebrates. The discovery of _Andreolepis hedei_ suggests that the cartilaginous skeleton may have evolved earlier than previously thought.

* This would mean that the cartilaginous skeleton may be the ancestral condition for vertebrates, and that the bony skeleton evolved later.