Is it possible to add on a site statistics page a graphic of some kind about percentage of the world species list recorded on iNat? Of course, numbers are not stable, but mean representation would be enough, I guess.
Do you mean, percentage of known or described species? Or percentage of all theoretical species?
Like the ratio (number of species taxa observed by all users) / (number of species taxa)?
Interesting question! This is already part of the taxon pages for groups where the taxonomy is considered complete. For example, for birds, you can see that users have recorded 9,462 of the 10,560 species recognised (89.6%). For a lot of other taxa, many of the names are only added to the site when those taxa are observed, so I guess the denominator (numbers of known species) would not be very reliable.
If we take it that there are around 1.9 million described eukaryote species, then the 252,082 eukaryote species recorded on iNat as of now make up 13.3% of that number. The true number of existing species is certainly much higher, but estimates vary widely. Using an estimate of 8.7 million eukaryote species, we have recorded 2.9% of those on iNat.
I don’t know if there’s a way to see how many species have been added to the iNat taxonomy but not observed yet, other than for those groups such as birds where the taxonomy is complete.
Known I think, theoretical amount differs from one author to another too much.
We have a number of undescribed salticids from NZ which we are tracking in a project and with fields. It’s not that they aren’t observed in iNat yet, it’s just that we don’t have the taxon to put them to!
I agree though, it would be interesting to see the ratio, even if the denominator was changing constantly as well.