500,000 Taxa on iNaturalist!

Fantastic - congratulations to everyone!

Wow! Great job! Sounds like we've got work to do :)

Incredible achievement! Not to mention that there are hundreds of undescribed species documented on iNat still waiting to be added to the formal count!

This post deserves a Pulitzer Prize.

@safron it looks like the search for lost birds project lists Bachman's Warbler, Imperial and Ivory-billed Woodpeckers, and Eskimo and Slender-billed Curlew all as species that could potentially be refound... I don't see any of the others on the map here at least but I agree Bachman's Warbler also doesn't seem realistic.

A great accomplishment. I hope those numbers will continue to increase.

Let's go!

Awesome!

What a cool milestone! I'm excited to see the data continue to grow.

I suspect a lot of described invertebrates (and various cryptic plants and fungi) are still waiting to be observed in North America and Europe, and it would be exciting to have a readily searchable database of those known or suspected ranges to help plan search efforts. That said, I imagine many of those ranges or type specimen localities have never been digitized and made publicly available in a useful format, so it would probably be a herculean effort for a person or small team to produce an even mostly-complete database of those ranges.

I know that some species or genera pages on iNat have certain jurisdictions (counties, states, etc.) highlighted in green or orange; I assume those represent ranges attested by literature? Is there a way for users to help fill in the gaps there, if for example we're able to find a source documenting observations or collections of a species or genus that doesn't have an "expected" range in the database yet?

Muchas felicidades a toda la comunidad!
Es un orgullo ser parte de este esfuerzo global!

Am I reading the table correctly that the Smithsonian recognizes 20 species of horseshoe crab while the IUCN only recognizes four species (all of which have been recorded on iNat)?

@hmheinz Smithsonian NMNH as a publisher includes some fossil taxa (hence the 20 species of horseshoecrabs) https://www.gbif.org/occurrence/taxonomy?publishing_org=bc092ff0-02e4-11dc-991f-b8a03c50a862&taxon_key=351 we prob should redo that table with just their "NMNH Extant Specimen Records (USNM, US)" dataset

Thanks for clarifying, @loarie I know that iNat does have some ability to record fossil taxa but as that's not really the main goal/audience, I imagine the numbers are quite low.

A comparison with data for Eswatini:
Estimated total taxa – 9,450
(Includes incompletely identified records and taxa with record information not yet sourced}
Records: Specimens 43,144; visual 265,065, iNaturalist observations 54,439 (29,760 research grade)
Confirmed taxa with record information – 7,997
(this figure has been used for calculation of percentages below)
Specimens – 5,888 taxa (74%)
Visual records – 2,069 taxa (26%)
(includes bird atlas records, alien plant surveys, EIA surveys, etc.)
iNaturalist records (research grade) – 4,001 taxa (50%)
iNaturalist records (verifiable) – 5,463 taxa (68%)

Hooray, We need more citizen scientists around the world!

It's exciting how big iNaturalist has gotten, but these statistics ring a little hollow given how heavily iNaturalist has leaned on taxonomic inflation lately : https://www.sciencedirect.com/science/article/abs/pii/S0169534704001715 . I don't know if these figures already count subspecies so that may cushion it somewhat, but iNat is a big part of the trend to describe any variation as its own species, so of course it means more 'species' have been observed. It doesn't always mean people are finding new taxa. If people split common dandelions into dozens or hundreds of species (yes thuis is something people are pushing for) you get dozens of new 'species', but it's meaningless really.

is there a project containing the 1st iNat record for each species?
There is https://www.inaturalist.org/projects/first-known-photographs-of-living-specimens but that is for the 1st photograph anywhere, not just in iNat, by my undertsanding.

Nice!
I believe this should include the caveat that prokaryotes (Bacteria and Archaea) aren't included in the total count?

@akbirder243 - the map is using the status on iNaturalist. Currently both of those are listed as critically endangered
https://www.inaturalist.org/taxa/10603-Paroreomyza-maculata
https://www.inaturalist.org/taxa/12958-Myadestes-lanaiensis
looks like both of those are referencing IUCN statuses. Its a bit tricky when IUCN clashes with Clements which is iNat's bird taxonomy provider, but in both of these cases Clements also lists them as not extinct.

I hear your point though that each of these are almost certainly extinct. But currently iNat is delegating when species cross the extinct threshold to external authorities like IUCN and Clements

Congratulations iNat, such a cool milestone! And the list of newly recorded species just keeps rolling and rolling on, I love it. It's several years out-of-date now, so it's in dire need of updating, but interesting to compare Alaska vs global observed described/known species. Some of the %s are very similar despite the change in scale. Here's the journal post with Alaska data and estimates.

Birds (98% global vs 99% resident/regularly occurring Alaska species). Mammals (66% global vs 72% Alaska). Fishes (44% global vs 26% Alaska). Insects (19% global vs 12% Alaska). Arachnids (14% global vs 10% Alaska). Flowering/vascular plants (we didn't use the same taxonomic units to compare, but generally: 42% global flowering plants vs 73% Alaska vascular plants). Mosses (18% global vs 28% Alaska). Lichens (23% global vs 27% Alaska). Overall unique taxa (23% global vs ~25% Alaska known species where checklists are available).

Crumbs. That is one impressive milestone. Well done to everyone!

Fascinating and inspiring! Looks like we need a few southern hemisphere bioblitzes....

@charlie yes, thank you for bringing attention to this. I am beginning to be concerned with the level of splitting going on. I think it is watering down the notion of what a species is. Frankly, I’m worried it is getting a little problematic & contains undertones of undesirable social commentary. Variation is an important part of a species’ adaptability & survival.

Note aside, I am so proud to have been part of this achievement, & to be part of this fantastic community of fellow nerds! iNaturalist is not only just my favorite social media, but also an invaluable resource for science in the modern day. The potential of this application is utterly endless. Cheers to all of you! Long live iNat!!

This is honestly a great milestone to hit, achieving the 500,000 species mark means that we are halfway there to observing 1 million species, all being gathered in a global effort by millions of people. Here are some interesting statistics that I would like to provide. As of writing, there is 221,885,881 observations with 500,848 species across 3,465,752 observers. For every 443 observations made on iNaturalists, a new species is added per averages. In order to achieve 1 million species, we would need about 443,000,000 observations to reach that milestone. So far, in 2024 with less than 2 weeks left to go we have 49,818,075 observations. In order to reach 443,000,000 observations and to reach 1 million species based on our averages here at the current rate we are observing new species for iNaturalists, we can expect to hit the 1 million mark around June 9th, 2029. (By simply adding all of the observations in 2024 to the current total number of observations, in four years exactly we will reach 421,158,181 observations, meaning we need about 22,000,00 observations to reach the baseline of 443,000,000 observations. In 2024, it took until June 9th to reach 22,000,000 for the year.) In a global community effort, it should take us around 4 years and 6 months to reach the 1 million species mark at the current rate we are going at. I would really love to see us hit this mark before then, which would be a massive and very impressive global feat for the iNaturalist community to strive for.

I would be curious to see graphs of rate of change over time, and numbers for what factors are most correlated with increase (e.g. just observation numbers, or new users, or established users visiting new locations...). I imagine if nearly a quarter of described species have been found so far, then the species accumulation curve is probably starting to slow down. On the other hand search effort could be increasing exponentially from new users joining, making a more linear graph...

is there a list of plants that have not yet been recorded on iNat or are there just too many of them?

Making a map for unobserved species for most invert taxa would be pointless since most of them are unobserved. However, could someone perhaps make a map of the type localities of all invert species that are observed? Or at least all arthropods.

@laurie if it's helpful I'd be happy to make a list for unobserved mosses of North America- I can just go through Flora of North America, unless there's an easier way :)

@chickeroni I love a good iNat forecasting challenge of when we'll hit certain milestones. As others have pointed out, the rate of newly recorded taxa per observation will change and generally slow as remaining species are generally more difficult to observe and identify. But other important factors are the rate at which observers and observations are increasing (almost certainly more important in the regions of loarie's maps with a lot of unobserved taxa), and the rate at which new species are identified in the existing pool of iNat observations that have not yet been reviewed and identified. Other factors, more minor I think, include user accounts being deleted affecting observations and identifications, and the classification of wild/captive status.

@insectilluminatigetshrekt I assume GBIF

@muir While I do agree with the points made by others about the rate of new species being observed, along with poor wording on my part (should vs could) I still think it's very possible that the 1 million species mark could be reached in 2029. Crazier things have happened after all, in fact, when I wrote my statistics almost exactly one day ago the species count was at 500,484 and now it's at 500,963 so we have already added 479 new species in just one day, which I think is really interesting. Regardless, I think if the general community can keep a good pace with a strong focus on South America and Indo-Pacific regions I like our odds of meeting (or even beating) the mathematically first possible date based on our current rate of observing new species. I think either way it would be a fun and interesting goal to try and complete because it would be a very impressive accomplishment to achieve.

Excellent! I'm glad to have contributed a few of these new species!

It rejoices me to be part of a community that has achieved such an extraordinary feat, based on the principle of collaboration and also empathy.
Comparing the number of species recorded in iNat with those of such an outstanding institution as the Smithsonian NMNH, allows us to measure the level of achievement attained.
The proposal of the challenge of doubling the number of new species of those carried out until now by a certain date is fun. Although mathematically it is possible; In the field (for those of us who are dedicated to searching for them), finding new species requires much more resources than those allocated until now in such searches. This is a variable that has not been considered, as well as forest fires and other events facilitated by the climate crisis, in addition to others that have been included or mentioned as difficulties. These factors will slow down the time to reach the established milestone, but it will eventually be achieved even if it is not in the established time.
Greetings and thank you for your efforts.

Me regocija ser parte de una comunidad que ha alcanzado tan extraordinario logro, basado en el principio de colaboración y también de empatía.
La comparación de guarismos de especies registradas en iNat con las de una institución tan destacada como el Smithsonian NMNH, permite dimensionar el nivel del logro alcanzado.
La propuesta del desafío de duplicar la cantidad de nuevas especies de las realizadas hasta este momento a una fecha determinada, es divertido. Aunque matemáticamente es posible; en terreno (para quienes nos dedicamos a buscarlas), encontrar una nuevas especies requiere mucho más recursos, que los destinados hasta hora en dichas búsquedas. Esta una variable que no ha sido considerada, asi como los incendios forestales y otros eventos facilitados por la crisis climática, se suman a otras que sí han sido incluidas o mencionadas como dificultades. Estos factores ralentizarán el tiempo para alcanzar el hito establecido, pero finalmente se logrará aunque no sea en el tiempo establecido.
Saludos y gracias por vuestro afán.

I was recently talking to a hover fly researcher here in Canada and when I mentioned neotropical hover flies he said something about them being hard and leaving them to South American colleagues in the field (of whom there aren't many...). I understand you can only research so many things at once and funding is hard and easier to get for local subjects that are more directly relevant, but I found it a bit disappointing. The challenge of the diversity and level to which neotropical species are unresolved is why we should be researching them!

The number of new species added to iNaturalist for the last seven years rounded to the nearest thousand in thousands ... 49t, 61t, 56t, 48t, 43t, 42t and 35t.

Truly amazing! The best community!!

@sjl197 Where does the IUCN even get their numbers for invert species?

We're up to 64 new mammals, birds, reptiles, and amphibians since this post!

Amazing!!!
Thank you for keeping the updates on this matter. I can't imagine what happens to plants or invertebrates, which leaves room for hundreds of other species!

They are crunched annually in the Year in Review - you can click on each month and see the new species from them:

@loarie Nice, but can I look at the trends for specific taxa, particularly non iconic taxa. For example, see how many myriapod species get added each year.

Awesome! I have two reptiles and one amphibian that I can maybe make a first on iNat! No birds though.