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Title: Sturgeon and paddlefish (Acipenseridae) saggital otoliths are composed of the calcium carbonate polymorphs vaterite and calcite: acipenseridae otoliths are vaterite and calcite

The otoliths of modern fishes are most commonly comprised of the metastable aragonite polymorph of calcium carbonate (CaCO3); however, sturgeons have otoliths reportedly comprised of the least stable of the three most-common polymorphs, vaterite. In this study, we used neutron diffraction to characterize CaCO3 polymorph composition of lake sturgeon and paddlefish otoliths. Based on previous summaries of CaCO3 composition over fish evolutionary history, we hypothesized that sturgeon and paddlefish otoliths would have similar polymorph composition. We found that despite previous reports of sturgeon otoliths being comprised entirely of vaterite, that all otoliths we examined in this study also had a calcite fraction that ranged from 17.9+ 6.0 wt. % to 35.9 + 2.9 wt. %. We also conducted a grinding experiment that demonstrated that calcite fractions were due to biological variation and not an artifact of polymorph transformation during preparation. Our study provides the initial characterization of the polymorph composition of the otoliths of lake sturgeon, and paddlefish and also provides the first-ever report of otoliths of Acipenserids as having a calcite fraction.
 [1] ;  [1] ;  [1] ;  [2] ;  [3] ;  [3]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  2. Southern Illinois Univ., Carbondale, IL (United States)
  3. Wisconsin Dept. of Natural Resources, Oshkosh WI (United States)
Publication Date:
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Journal of Fish Biology
Additional Journal Information:
Journal Name: Journal of Fish Biology; Journal ID: ISSN 0022-1112
Wiley - Fisheries Society of the British Isles
Research Org:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). High Flux Isotope Reactor (HFIR) and Spallation Neutron Source (SNS)
Sponsoring Org:
Country of Publication:
United States
60 APPLIED LIFE SCIENCES; calcium carbonate; otolith; fish; neutron diffraction; vaterite; calcite
OSTI Identifier: