The species are all modern bony fishes, suggesting that elastic cartilage is a general feature in this group, according to the study, which was published Jan. 9 in the journal Nature.

This cartilage eventually became further elaborated to form the prominent outer ears of early mammals. An additional surprise was that the elastic cartilage of gills may have arisen much earlier ...

The species are all modern bony fishes, suggesting that elastic cartilage is a general feature in this group, according to the study, which was published Jan. 9 in the journal Nature.