Change to Ancestor Disagreement Implementation

I wait for the new way to handle Ancestor disagreement

I think we can make a small change that would make it so if the taxon that an ancestor disagreement is disagreeing with has been withdrawn or deleted it is counted as a non-disagreement - @loarie 25 Feb


That improvement is live overnight!
minor ancestor disagreement change is live
@loarie 29 Feb

@silversea_starsong this new DQA would be for an obs of a sea urchin and a fishie and a bit of seaweed (which you would never do, so you won’t be affected). 3 pictures should be 3 obs. The other problems must wait for their own solution.

I would prefer to keep the Help answer simple and straight forward
Question - fish and seaweed?
Answer - new DQA until obs splits to 2 separate obs
(but using your text)
If this, then that - is confusing people muchly.


great. now if anyone ever does an ancestor disagreement on my obs, i’ll just withdraw my original id, and then make the same id that they disagreed with. no more disagreement, and i get my way in the end. problem solved!


Hmm… I hope that’s not how it works. My understanding would have been that only the ancestor component of the disagreement is removed. So if you identify the hoverfly as ‘Eristalis tenax’, and Bill adds a disagreement to ‘Family Syrphidae’, if I then add ‘Eristalis arbustorum’, and you withdraw your original ID, Bill’s ID should still disagree with Eristalis tenax, but no longer disagree with ‘Genus Eristalis’ and every other taxon up to Family. @loarie is that right?


I moved posts from
Here since they seemed like a separate topic that might get a lot of discussion.

Apologies @dianastuder I couldn’t split your second comment which deals with both topics (disagreement and new DQA), but figured this was the best approach.


i actually tested it, and it looks like what happens is they’ve effectively made every ancestor disagreement what they were calling a “leading” disagreement instead of a “branch” disagreement.

i guess that prevents me from doing what i was describing, but it’s sort of unexpected nevertheless. i wonder how many people realize that their ancestor disagreements are now only “leading” disagreements rather than “branch” disagreements?


Changing the HARD disagreement - which yelled - I disagree with ALL of you, without even seeing your ID
to soft disagreement.

Plant + sp + same sp = RG
But if that ‘plant’ was counted as hard disagreement, we needed 3 at sp for RG.

It was okay for
Species A
Hard disagreement to - don’t know what it is, but it is NOT Species A
Then need 3 to agree to species B, which was 4 to agree because of Ancestor Disagreement.

I will no longer have to explain that ‘species B is not a plant’ altho you and I both know it is. I have made a few scientists quite angry as I try to explain - you are guilty of unintended and surreptitious Ancestor Disagreement. Ouch.

Now when the wrong ID is withdrawn or deleted - iNat will graciously revert to what iNatters expect
Plant + sp + same sp = RG


Will be Eristalis arbustorum at Needs ID, supported to Family.

If @pisum then adds Eristalis tenax again
we will have Eristalis needs ID, supported to family.
pisum has only that one ID to use.


I’d be curious to see any stats for how this impacted, for example… number of observations of Diptera that were previously at the level of order and then changed rank following the change to a lower level.

Was the impact on the dataset recorded/ are the historical numbers accessible ?

This change would seem to impact ( help with) a significant number of the observations I come across trapped at higher levels.

Great this was finally implemented anyhow.
In general I think use of “leading disagreement” over "branch disagreement"makes a lot more sense.

Be amazing to also see support for an algorithm tweak in situations where you have 5 people in agreement the original ID of a wasp is actually a fly, but you still have to counter the erroneous initial ID with three specialist IDs at each finer level… this is another prime suspect when it comes to iNat functionality which traps things illogically at coarser levels.


Ah. I had an observation pop up on my notifications today where I had added a genus-level disagree with a species ID and the user had changed their ID to a different species within the same subgenus as their original ID – and I couldn’t figure out why the algorithm wasn’t continuing to treat my previous ID as a disagreement with the current ID, the way it has always done in the past.

Happy to see this change, but it really deserves an official announcement rather than leaving people to figure out by chance that the site suddenly works differently in non-obvious ways that are relevant to our regular activities.


Thanks to @cthawley we have a forum post at the title.

I expect this to be in the monthly iNat News and Updates.
And also in @tiwane 's new Help answers.

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Seems not to be applied retrospectively?

EDIT ( did the DQA trick of saying “no good as it can be” and then flipping it back…and this fixed it …previously it was at the level of order)

However, this has 2 IDs at species level, 1 historical ancestor disagreement… and doesn’t go to RG - even when DQA flipped to good as it can be.

Regardless, at species level now!
And this observation is a good example of why this change is important.
Only observation of this species on iNat.
Trapped at level of order for the last 3 years.


if you notice any older obs in this state, please withdraw/restore your ID to force to refresh. Thanks!
@loarie today on the iNat blog post linked at the top

PS add an ID then withdraw to force it to refresh. It is now RG as expected.


The DQA flipping only took it as far as needs ID, but it did flip it from order to species.
Good to know re:adding an ID and withdrawing, thankyou.


Is there any way to search for older obs which might now be trapped and can be released? E.g. under the pre-mavericks? ( thinking of observations I may have already reviewed but are still at coarser level than needed …and how to find them without sifting back through everything )

I can search for mine via my copypasta comments. (Have whined since August 2022 my first comment on That blog post)
But otherwise I will have to wait for them to bubble up via my notifications.

Otherwise tweak taxon and location from this URL - mine is plants above family on the Cape Peninsula. Not tethered to Ancestor Disagreement, but trapped in limbo since botanists work from family filters.
Tick Reviewed for the ones you have already looked at? But that is daunting!!

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Or Kingdom Disagreements for the ones trapped at Life (mine is for Africa)

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I’m at least glad I read about this in the forum (un-advertised on the main site more or less…). I don’t really know that this is what I wanted out of such ID interactions, especially in scenarios similar to Matthew’s example where my disagreement up to a quite higher rank than the one I was disagreeing with is one where I have provided the ID at a high rank exactly because I did not want to provide a lower one, if that makes sense. Perhaps I’m not understanding the overall thrust of th change though.

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If you disagreed with species A
would you not at least like to see and consider species B
before iNat shows you as disagreeing with species B
? Maybe, on due and careful reflection - you might have agreed with B.
CID will now land at the taxon level where all 3 agree.

I do a lot of identifying of Unknowns - for the Western Cape and then Africa.
I follow my notifications, and if an ID slips back to where it needs a fresh DISagreement I will add that. Mostly because identifiers can get lost in the convolutions of CID (before this tweak too) I have learnt to check the effect of my ID - is it doing to CID what I expected it to.

If you come across a glitchy obs you can @mention loarie - but only after forcing the system to refresh. If the glitch is on your own obs you can link to it on this thread.

PS very happy with your fine example - first obs of this sp - trapped at order for 3 years!!!