Friday January 13, 2023
PhysOrg —
A new study led by the University of Vienna in which the Institut de Ciències del Mar (ICM-CSIC) has participated reveals that fishes living in the dark part of the oceans (essentially below 200 m depth in the water column) would likely decrease in size with climate warming, which may have important ecological effects.
The details of this research are reported in an article published Jan. 11 in Proceedings of the Royal Society B. For its preparation, the authors retrieved fish otoliths—small stones in the inner ear of bony fishes that facilitate the fishes’ sound and balance perception—from sedimentary formations dated 800–700 thousand years ago from the island of Rhodes in the Aegean Sea and measured them to track changes in fishes’ body size through glacial and interglacial periods.
The morphology of these structures is particular to each fish species and their size directly reflects the size of the fish individual they come from, which allows researchers to identify them in order to reconstruct past fish faunas.
“Thanks to the otolith analysis we have found that fishes during the interglacial period were smaller in size by 35%, when the global temperature had increased by 4 °C, which could happen again nowadays due to the ocean warming,” explains the leading author of the study, Konstantina Agiadi, from the University of Vienna.