Bony fish

Bony fish or Osteichthyes are a taxonomic group of fish that includes the vast majority of fish species. They are characterized by a skeleton that is significantly hardened by calcium, distinguishing them from other fish such as cartilaginous fish and jawless fish. Bony fish are found in both freshwater and marine environments around the world.

Classification

Bony fish are divided into two major groups: the ray-finned fish (Actinopterygii) and the lobe-finned fish (Sarcopterygii). The ray-finned fish are the most diverse and comprise the majority of bony fish species. The lobe-finned fish include the coelacanth and the lungfish, as well as the tetrapods, which evolved from a lobe-finned fish ancestor.

Anatomy

Bony fish have a number of distinguishing features. They have a hard, bony skeleton, a swim bladder for buoyancy, and gill covers called operculum. They also have scales and fins, which can be either ray-finned or lobe-finned depending on the species.

Evolution

The first bony fish appeared in the Silurian period, around 420 million years ago. They evolved from earlier, jawless fish. The evolution of the swim bladder allowed bony fish to become the dominant group of fish by the end of the Devonian period.

Ecology

Bony fish play a crucial role in aquatic ecosystems. They are a key part of the food chain, serving as prey for a wide range of predators including other fish, birds, and mammals. Some bony fish are also important predators in their own right.

Human interaction

Bony fish are of great importance to humans. They are a major source of food, and fishing for bony fish is a significant industry. Some species are also popular in aquariums.

See also

• Fish anatomy
• Fish classification
• Fish evolution
• Fish in culture