Herrings and Anchovies

The herrings and anchovies (Cluepeopmorpha) are a group of teleost fish that include 300 species. The group is present in the fossil record back to the early Cretaceous. An interesting characteristic of herrings is that their swim bladder is modified and extended to the brain case where it serves to enhance sound in the inner ear. Herrings and anchovies form large schools and feed on plankton.