Species search doesn't include intergrade observations

[cyanfox]

Please fill out the following sections to the best of your ability, it will help us investigate bugs if we have this information at the outset. Screenshots are especially helpful, so please provide those if you can.

Platform (Android, iOS, Website): Website, but probably all platforms

App version number, if a mobile app issue (shown under Settings or About):

Browser, if a website issue (Firefox, Chrome, etc) : Chrome

URLs (aka web addresses) of any relevant observations or pages: https://www.inaturalist.org/taxa/18230-Colaptes
https://www.inaturalist.org/observations?verifiable=true&taxon_id=18230&view=species&rank=species%2Csubspecies%2Cvariety&place_id=any

Screenshots of what you are seeing (instructions for taking a screenshot on computers and mobile devices: https://www.take-a-screenshot.org/):

Description of problem (please provide a set of steps we can use to replicate the issue, and make as many as you need.):

Step 1:
Go to Colaptes
Step 2:
View species
Step 3:
Notice how the ranks included are species, subspecies and variety? This means the observations of Colaptes auratus luteus × cafer are not counted, as it is an infrahybrid.

Now, including infrahybrids in the search wouldn’t work, as there are infrahybrids between different species, like Anser anser domesticus × cygnoides domesticus. And why would these be included when hybrids aren’t? So either the infrahybrid rank should be split, perhaps into intergrade and infrahybrid, or another fix should be implemented.

[maxkirsch]

Colaptes auratus luteus × cafer is a subset of Colaptes auratus—why would it be listed separately?

[maxkirsch]

also, you appear to have restricted your search to only observations identified at the ranks species, subspecies, or variety, so any observation ID’d to a different rank (e.g. infrahybrid) wouldn’t be included in those search results anyway. (the default search isn’t restricted to observations with IDs at those specific ranks)

[cyanfox]

I didn’t. iNaturalist did. The problem is that iNaturalist links to a search that omits intergrades. Intergrades are currently ranked as infrahybrids, hence why they are omitted.

I think the solution to this problem is to create a new rank, intergrade, with rank_level 5, which will replace infrahybrid for all “hybrids” between subdivisions of the same species. Infrahybrid will then be reserved for hybrids between subdivisions of different species. I think it’s useful to separate the two concepts anyway, even if there is another way to fix the problem described in this bug report.

I think most infrahybrids are intergrades. But most observations of an infrahybrid are of interspecies infrahybrids. So the majority of infrahybrids will need to have their rank changed, but most infrahybrid observations will be unaffected.

[cyanfox]

I don’t mean that it should be listed separately. I mean that its observations should be counted among the Colaptes auratus observations.

I don’t know of any cases in which all iNat observations of a species are intergrades. But if there was such a case, the count of species observed would not include it.

[maxkirsch]

Oh, i see now—clicking on “view all” under “total species observed” is what restricts the search to those ranks

[wildskyflower]

In the only previous discussions of the meaning of infrahybrid I can find and here, curator have assumed is that infrahybrid is intended only for a hybrid between two subspecies of the same parent species. I think the other case for an interspecific hybrid where one of the parents is identified to subspecis, there is no reason you can’t just call that a ‘hybrid’:

@jdmore

InfraHybrid: not as certain about the intent of this rank, but if analogous to the others, it would be for hybrids between different subspecies (varieties, etc.) of the same species, parented directly to that species. Hybrid formulae between subspecies belonging to different species would fall under the rules for the iNaturalist rank Hybrid instead.

@aspidoscelis

@birdwhisperer

That’s an infrahybrid or intergrade, a crossbreeding between two subspecies of one species. I’m talking about a subspecific hybrid between two species.

Though this is a common terminological distinction (at least in animals—this usage of “intergrade” is rare, in my experience, among botanists), I’m not aware of a reason why the two cases should be treated differently either in terms of the nomenclatural codes or on iNaturalist.

[cyanfox]

If infrahybrid is only intended for hybrids between subdivisions of the same species, not for hybrids between subdivisions of other species, then I’m not sure why the species search doesn’t include infrahybrid. Also, according to this, all hybrids between subdivisions of different species, such as Domestic Greylag × Domestic Swan Goose (Anser anser domesticus × cygnoides domesticus, should be removed, and perhaps a restriction on adding infrahybrids to hybrids should be implemented.

Interspecies infrahybrids. Currently, I know of 18. If these are useful, perhaps another rank should be created for them, as infrahybrid is intended for intraspecies hybrids.

By the way, I also forgot that form should be included too. But alas, Weeping Crack Willow (Salix × pendulina) has two forms. Perhaps the infrahybrid rank should have been used for these two, as it seems to be used for any subdivisions of a hybrid.

Or maybe iNat should stop being lazy and properly distinguish subspecies, varieties and forms. They all have rank_level 5, but they are not equal. Outside of iNaturalist, variety is below subspecies and form is below variety. Subspecieshybrids should perhaps be distinguished from varietyhybrids and formhybrids.

[cyanfox]

I think that given that people will use ranks like infrahybrid and forms, and maybe even subspecies, at least formerly, for subdivisions of interspecies hybrids; I reckon the observations search needs a way to exclude interspecies hybrids that doesn’t get tripped up by this, so it can be used for the species count/search.

Maybe an hybrid parameter, which if set to no, prevents any observation from showing up if its observation taxon is hybrid or genushybrid, or a descendant of such a taxon? If it’s set to yes, then observations will only show up if they are hybrids, genushybrids, or descendants of such taxa. If any, then everything shows up.

[cyanfox]

I think the solution should be to implement this:

https://forum.inaturalist.org/t/replace-hybrid-ranks-with-a-hybrid-level-property/75172

Then species search should allow all ranks species and below, but require hybrid_level to be less than 10.