System Deletes Hybrid Taxon Framework Relationships

Curators
1

POWO includes a number of hybrid plant taxa in its taxonomy, including approximately 3,000 that it notes are “artificial” hybrids, but otherwise are a perfectly ordinary record. Here is an example of what the POWO page for such a taxa looks like. As you can see there is no indicator that the taxon is either not accepted or synonymous with anything else. In fact, the page explicitly says “POWO follows these authorities in accepting this name:”. In my experience POWO’s list of artificial hybrids is curated and they will respond to emailed questions about their choices for artificial hybrids just like they would for any other taxa.

When I was starting as a curator, I went through the taxon framework ‘unknowns’ and added a bunch of taxon framework relationships to such artificial hybrid taxa, properly listing the name, parent, and link to POWO.

At some point, another curator informed me that the system would automatically go through and delete all such taxon framework relationships once a month or so, putting them back to ‘unknown’, so adding them is a complete waste of effort.
This appears to be true, as the system indicates there are no old artificial hybrid relationships created by me.

As far as I know, this is a completely undocumented behavior. I can’t find any forum post or curator guide entry that even alludes to the system doing this.

Apparently, the ‘proper’ way to create a taxon framework for an artificial hybrid is to make it ‘not in external’, and then include a comment like “Artificial hybrid in POWO: https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:77210603-1”. There are hundreds of taxon framework relationships with that verbatim comment (except for the link). However, even very experienced curators continue to sometimes just add taxon relationships for artificial hybrids in the ordinary manner, probably unaware the system will just delete them eventually.

I think this behavior is inconvenient because it unnecessarily adds hundreds of of ‘deviations’ and ‘unknowns’ for taxa that in fact are accepted as artificial hybrids in POWO, and the fact that it is completely undocumented results in an unknown amount of lost volunteer curator effort.

Can the automated system be changed to not delete these records, or at the very least could this behavior be documented somewhere to warn curators?

1 Like
2

I’ve seen similar behavior with other taxon frameworks, such as deleting accepted fossil names or unreplaced junior homonyms, and I think that’s a choice by iNat staff. If you search flags for “TFR keeps getting deleted” you’ll find a history of my complaining about this.

3

They are being deleted because those taxa are not actually accepted by POWO. Instead, POWO only accepts a name for the taxon. Accepting a name and a taxon are not the same, as I told you before when I warned you about the relationships you were making being deleted.

Note the difference between the two linked pages:
× Amelasorbus jackii “This hybrid is accepted”
× Amelasorbus raciborskiana “This is an artificial hybrid”

In visiting the taxon page for the parent taxon, × Amelasorbus, you will notice only one of these two taxa listed under “Accepted Species.” This is because the taxon designated an artificial hybrid is not an accepted taxon. Again, accepting a name is not the same as accepting the taxon.

As curators, we are told to broadly avoid adding or maintaining hybrid taxa. This applies to all hybrids, especially when they are not accepted by the framework being sourced, as is the case here. Personally, I do enjoy wild hybrids, but iNaturalist is not intended to be a repository for observations of every taxon ever described. Artificial hybrid taxa fall into the bin of taxa that should not be added or maintained, with fossil taxa and cultivar names.

You are right that automated/staff-side taxon framework relationship behavior should be described in a place for curators to read somewhere. This behavior can occur under other circumstances, and is the reason for my feature request here: https://forum.inaturalist.org/t/generate-a-taxon-history-entry-when-taxon-framework-relationships-are-modified-deleted/54458

Edit: Forgot to mention that any improperly formatted taxon relationship will be deleted automatically. iNaturalist seems to detect and delete relationships that do not correspond to a real entry in the framework source. In my experience this applies to misspellings, inaccurate URLs, taxa that are not listed in the source as accepted, and possibly more.

5 Likes
4

Thank you for this clear-cut example! I’ve wondered about this, too.

5

You can also look directly at how POWO exports the machine-readable data that inat uses for those two taxa::

2941344|721290-1|Species|Accepted|Rosaceae|×|Amelasorbus||jackii||||Rehder||J. Arnold Arbor.| 6: 154|(1925)||NW. U.S.A.|tree|temperate|× Amelasorbus jackii|Rehder|2941344||||2941342|721290-1|Amelanchier alnifolia × Sorbus scopulina|N,,,,,,,,,,,,,,

vs

2941345|721291-1|Species|Artificial Hybrid|Rosaceae|×|Amelasorbus||raciborskiana||||Browicz & Bugała||Arbor. Kórnickie| 3: 78|(1958)|||||× Amelasorbus raciborskiana|Browicz & Bugała|2941345||||2941342|721291-1|Amelanchier asiatica × Sorbus sp.|N,,,,,,,,,,,,,,

and you can see that the only difference in the formatting is that cell 4 is ‘Accepted’ vs ‘Artificial Hybrid’.

Because the behavior is not documented, It is not at all clear to me that it isn’t just a software bug, where there is some psudocode like:

if not (inat.tfr.name == powo.name and inat.tfr.rank==powo.rank and powo.status=='Accepted'):
    delete(inat.tfr)

where it should be something like

if not (inat.tfr.name == powo.name and inat.tfr.rank==powo.rank and (powo.status=='Accepted' or (powo.status=='Artificial Hybrid' and inat.tfr.rank=='Hybrid'))):
    delete(inat.tfr)

I think it is not surprising that the software does not support fossil taxa, given that the staff themselves also manually mercilessly delete fossil taxa sometimes, such as when @tiwane summarily deleted all the extinct hominids. This makes sense because fossils do not really have any direct present ecosystem impact.

The difference with artificial plant hybrids is that they inevitably are a significant part of the inat dataset whether we want them to be or not. And have just as much present ecosystem impact as any other taxa; the ecosystem does not care whether humans categorize an invasive species originated as a ‘species’, ‘natural hybrid’, or ‘artificial hybrid’. I think the fact that POWO already curates a fairly short list of artificial hybrids (~0.7% of the accepted species POWO in the POWO database) is an advantage for us, because it reduces the need for curator workload to make decisions about deviations ourselves, and eliminates the potential ‘handling every single plant cultivar’ issue you mentioned.

Also, the system’s lack of any handling of artificial plant hybrids is responsible for the majority of all identification errors in the taxon that I work on, which I expect is typical in other plant taxa that contain common ornamental plants. All other CV errors rapidly and semi-permanently get better after one quick ID blitz to correct them, but artificial hybrids get assigned to other species at random, and do not get better when fixed because they are not in the CV. This represents a constant and unfortunate source of wasted IDer workload. I think allowing TFRs for hybrids is basically just a step in the direction of reducing wasted volunteer effort.

1 Like
6

How odd that the policy is to hypersplit any variation as its own species, even if there’s no hope of getting IDs for them on the site, but to ignore the wide diversity of hybrids that actually DO have value in documenting them. I wish more people would speak up as to the many problems with how iNat deals with taxonomy, it’s really inconsistent and doesn’t address a consistent audience either. I don’t see the downside in being able to document hybrids. Sigh.

1 Like