Trace element–protein interactions in endolymph from the inner ear of fish: implications for environmental reconstructions using fish otolith chemistry†

Abstract

Otoliths, the biomineralised hearing ‘‘ear stones’’ from the inner ear of fish, grow throughout the lifespan of an individual, with deposition of alternating calciferous and proteinaceous bands occurring daily. Trace element:calcium ratios within daily increments measured by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) are often used in fisheries science to reconstruct environmental histories. There is, however, considerable uncertainty as to which elements are interacting with either the proteinaceous or calciferous zones of the otolith, and thus their utility as indicators of environmental change. To answer this, we used size exclusion chromatography-inductively ..