Proteins from fossil otoliths of fish

Otoliths are calcium carbonate components of the inner ear in teleost fish. Otolith morphology and carbonate mineralogy is influenced by proteins present in the environment where biomineralization took place. However, in the fossil record proteins incorporated into biomineral structure are mostly lost through diagenesis. The published paper reports the presence of 11 fish-specific proteins in Miocene (over 14 Ma) phycid hake otoliths. These fossil otoliths exhibit microscopic and crystallographic features indistinguishable from those of modern representatives. Identification of identical proteins in modern and fossil phycid hake otoliths implies a highly conserved inner ear biomineralization process through time.