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Stephen Gaimari <[log in to unmask]>
Reply To:
Stephen Gaimari <[log in to unmask]>
Mon, 7 May 2012 12:06:49 -0700
text/plain (115 lines)
Addressing Kip's statement:
"As I understand it, the folks at CDFA here in California that do the
official identifications, say that sample A *is consistent with* Aus bus
and not that A *is* Aus bus."

Just to clarify that this is not correct. We only use the "is consistent
with" for DNA based identifications (e.g., DNA consistent with Aus bus),
with the obvious reason being that not all species are in the sequence
databases, some present in the databases may be misidentified, and we
are dealing with many samples of unknown exotic origin. The vast
majority of our identifications are morphological. But we might have a
situation where we have a larval sample which can only identified to
genus (or family), or we have doubts about a species identification, so
sequencing COI (or some other relevant gene region) will tell us what
taxon the DNA is consistent with.


Dr. Stephen D. Gaimari
Program Supervisor (Entomology)

Plant Pest Diagnostics Center
California Department of Food and Agriculture
3294 Meadowview Road
Sacramento, CA 95832, USA

Tel. 916-262-1131, Fax 916-262-1190
E-mail  [log in to unmask]

-----Original Message-----
From: Entomological Collections Network Listserve
[mailto:[log in to unmask]] On Behalf Of Kipling (Kip) Will
Sent: Monday, May 07, 2012 11:22 AM
To: [log in to unmask]
Subject: Re: insect identification success rates

I think that the proportion of "correct" and "incorrect" identifications
is not such a useful number, or at least it is so context specific (as
alluded to in previous posts) that it is a number that might be readily
manipulated to make any point.

What would be more interesting is when errors do occur, at any rate,
why, and is it due to a systemic problem such as a method built on
faulty premises or is it due to an underlying weakness in the background
information available to work with, e.g. incomplete or poorly done
taxonomy, poor sampling of the variation in the character system or a
highly discordant species concept? Or, is it just plain old sloppy,
eye-balling things that look similar by someone that just isn't into
doing identifications.

Just qualitatively, when I have checked vouchers of "morphospecies" used
for some ecological studies the error rate was over the top, while a
person, but not an expert, that worked diligently with existing
literature and coaching had a pretty reasonable error rate and finally,
following up on experts in material they examined in museums I see a
very high level of accuracy, but definitely it represents the state of
the art at the time of determination. The latter is a case of high
precision, but low accuracy. A moving target, however.

As I understand it, the folks at CDFA here in California that do the
official identifications, say that sample A *is consistent with* Aus bus
and not that A *is* Aus bus. It might seem a bit of careful legalese,
but a perspective which always includes some uncertainty, the level of
which is based on the sample and background knowledge, would serve us
all well.


On 5/7/2012 8:26 AM, Colin Favret wrote:
> Does anyone know of a reference that attempted to quantify the 
> proportion of correctly identified insect specimens of any group in 
> any context? Obviously, there is a wide range of proportions of 
> correct identification depending on who did the IDs, how long ago they

> were done, what taxa were IDd, what taxon concepts were used, etc., 
> etc. I know of publications quantifying ID failings in molecular 
> databases; just wondering if anyone has ever looked into the issue 
> with respect to the specimens themselves. I'll post a summary if I 
> find out anything at all.
> Many thanks, Colin


Contact info:

Kipling W. Will
Associate Professor/Insect Systematist
Associate Director,Essig Museum of Entomology

send specimens to:
Essig Museum of Entomology
1101 Valley Life Sciences Building, #4780 University of California,
Berkeley Berkeley, CA 94720-4780

letter mail to:
130 Mulford Hall
ESPM Dept.- Organisms & Environment Div.
University of California
Berkeley, California 94720

phone 510-642-XXXX
fax 510-643-5438