dwc VS tag

I'm a data librarian, so ideally the system would be built around the concept of collections, and support a solid metadata schema like Darwin Core.

With regards to longevity, when we're planning our infrastructure and how we're actually going to store our digital data we have to think in the long, long term (100+ years), much as we have to when considering how to store the physical specimens. Currently we manage our own data centre which stores all our collections and image data but we’re exploring cloud options currently. In terms of how we store the actual data, we try to map to well known standards and ontologies (such as Darwin Core - https://dwc.tdwg.org/) to ensure our data is interoperable with others and can be managed using community standards. On the Data Portal specifically, we use a versioning system to make sure that data is available long term, even if it’s been changed since it was originally made public (this happens regularly as taxonomists love to reclassify specimens!). This is particularly important when users cite our data using DOIs which should be persistent and always available.

Nature + Identifiers is an issue (e.g. see https://github.com/tdwg/tag/issues/36). I've routinely mentioned to others in my field to look at other industries for ways forward, particularly ones like the music industry, so its interesting, if unsurprising to see all the same problems arise there. For those who know, in our field, when Identifiers comes up in conversation at conferences etc., we tiptoe away, somehow people can't learn from the past issues.

There are two issues that keep coming up in my mind 1) People want Identifiers to do something (like resolve), rather than just be identifiers and 2) People think that there are such things as "unique" identifiers (one identifier per "thing"). Neither, in my mind, are the purpose of identifiers. Identifiers should do one thing, localize you to some concept. By localize I mean that if you can find the digital space (or in physical collections where identifiers are used the physical "printed" identifier) that "contains" the identifier then you should have a reasonable probability of finding the thing/concept that identifier is for. That's all. No certainty, no uniqueness. It's very akin to what we do when we cite something in a publication, we are giving the research a reasonable chance of finding the origin. This isn't to say that we shouldn't try to keep identifiers unique though, it's to say that when it comes down to crunch time we should never assume 1) they are unique, and 2) that their special properties (e.g. that they resolve) actually work.

I've seen numerous identifier schemes come and go, we've specifically designed a 1-many for our things-to-identifiers in our systems (sitting on top our internal IDs). DOIs? They must be unique, right? Nope. Institutional CODENs? Nope (though the botanists have done it pretty well through community peer-pressure).

As others have noted, identifiers really are just labels, though things like UUIDs have the game-changing property ofreducing the probability that you're looking at a homonymous label.