Funding for this research was provided by:
Deutsche Forschungsgemeinschaft (Me 1686/5-1,5-2)
Received: 6 July 2018
Accepted: 18 December 2018
First Online: 29 December 2018
Ethics approval and consent to participate
: A permit for collecting fish samples was not needed, because all fish from contemporary populations were taken from the catch of commercial fishermen. No fish was killed for the purpose of this study.
: Not applicable.
: The authors declare that they have no competing interests.
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