Do older observations have more misidentifications?

[petezani]

@paul_dennehy

I suspect that while newly posted records may be misidentified, there is probably an observation age by which someone knowledgeable will have likely corrected mistakes, so older observations may be likelier to be correctly identified. Or do older obs have more misidentifications because the CV was worse back when they were posted? Has anyone tested this?)

Tested this formally? No, but I have done exhaustive identifying of all observations of a number of well-observed lizard species (I think I have over 1000 IDs on over 25 species of lizards). Here’s what I’ve noticed.

Newly posted records seems to be misidentified more than older observations probably because there are more recent observations and more eyes have been on the older observations, as you suggested. However, I have found a number of observations with multiple agreeing identifications (three, four, five, I think I even found an observation with seven wrong IDs once) that were (in my opinion) incorrect. Mainly it was when species were visually similar to another closely related, but sympatric species in the area. For example, hatchling and juvenile iguanids can be notoriously hard to identify based on color or pattern, but their tails and throats are reasonably recognizable making them ‘easy’ to identify with practice. So older observations aren’t free from errors, but they probably are less error-prone in some situations (if the CV became aware of that species early on, if that species has a champion, if it is ‘easy’ to recognize, etc).

The other thing to consider you didn’t mention is more specifically about the community of identifiers in that region. Most users identify regionally at best meaning a single area usually has the same identifiers that slowly get replaced geographically. So, if that community isn’t as strong at catching that initial errors, they get buried in four observations (that number of IDs showed again and again it seems) all of which are incorrect. So, the age of the observation doesn’t seem to allow for easy correction unless someone is a “complete-ist”, like me.

So, I think older observations have way fewer errors numerically (or even proportionally) merely because more time has elapsed for correcting ID issues and solid identification communities have developed in many geographic and taxonomic areas. For example, the community of lizard identifiers in the U.S. was strong before I even found it.