Thanks @sharif.islam. You write that at PID kernel contains key:value pairs & that every attribute depends only on the identified object and nothing else. What I assume this means is that under no circumstances does PID kernel metadata change. It is the canonical identity of the thing. The “thing” here is the digital object itself and nothing more, inclusive of the physical specimen from which it was derived. Provenance is held elsewhere in the searchable (editable? static?) metadata. Have I mischaracterized this? What then is the verifiable thread (checksums?) that ties the searchable metadata to the kernel PID metadata for humans or machines to verify that the digital specimen object is unique and persistent with respect to its physical counterpart?
To be sure, these are technical matters, but they outline a socio-technical contract, ownership, and chains of responsibilities. Who is it that creates the kernel PID metadata? And, as a result of that action, do they assume responsibility for the unequivocal link between it and the physical specimen even if the latter were transferred to another museum? I suppose this would be comparable in spirit to what happens when a publisher is purchased by another. Although branding can be inferred by a DOI prefix, under these circumstances, the purchasing publisher must accepted the fact they then become responsible for the prefix.
And here, I strongly think we have to consider using existing domain related standard as EML. It seems to me using it, Digital Specimens can win opportunities to be linked “more easily” with others 1/ domain (ecology) related Research Objects (as genomics data, GIS data, not-occurences oriented data… and also softwares, workflows, publications, protocoles…) using EML terms and with 2/ extra domain (not ecology related) RO using notably EML annotation module facilitating addition / inclusion of terminological resources