Specimen Determination

Introduction

     Determinations are what zoologists* call the scientific names that are given to specimens in a natural history collection or museum.  Determinations are a type of identification - but they differ in a few subtle, but important, respects.

     With one exception mentioned below, Biological Determinations are not 'objective facts' but rather are 'opinions' or 'hypotheses' created by scientists related to the biological identity of particular specimens.  As such, they may change over time or be debated and disagreed on by different scientists.  Like most opinions, your confidence in them may be affected by information about the determinor, the resource they had available and the method by which they arrived at the identification.

      Determinations include additional information, over and above the biological name being given to the specimen.  A determination often has a determinor and a date of determination.   This information allows a researcher to place the determination into a context that may affect their confidence in the determination.  For example, one may have extremely high confidence in a beetle determined by a noted expert for the genus to which it belongs, but you might be skeptical of a moth identified by the very same expert.  Likewise, knowing when a specimen was determined might also influence your confidence; either because it was determined early in an expert's career or perhaps prior to the publication of important taxonomic works associated with that taxon.

      It is extremely common in a natural history collection to find specimens which have been determined more than once.  In some cases these determinations agree on the identity of the specimen - providing increased confidence in the identity.  However, in many cases they disagree, leaving a researcher to choose which of the determinations to trust.  

How OSAC treats determinations.

     OSAC contains nearly 3 million insect specimens.  The majority of these specimens are identified at some taxonomic level (i.e., Family, Genus, Species or Subspecies).  However, as is the case in most entomological collections, many of these specimens lack formal determination labels. 

     Our history extends back nearly 150 years, and for most of that time, curators and expert taxonomists often placed specimens into 'groups' - either in small cork/foam bottomed boxes called unit trays or merely by pinning them in close proximity in a larger drawer - and provided a single determination label for the group, or series.  In some cases, no determination label at all was provided, and a taxonomic name was simply written or typed on a header label positioned on the unit tray or pinned in the drawer above/below the series.  As a result of this practice, there is a large disparity in the level of confidence in our determinations, ranging from specimens that possess actual determination labels written by experts in these groups to specimens that sit in a unit tray which bears a formal biological name; but which lack any information about who/how/when they became associated with this biological name.

     In our digitization effort, OSAC keeps track of this information, so that users searching our holdings online can evaluate the determinations of our specimens for themselves.  We try to categorized all of our determinations into the following types - ranging from high confidence to low confidence:

(A) Type specimen (holotype, paratype, etc) see below,
(B) Specimen bears determination label by named determinor 
(C) Specimen bears determination label by anonymous determinor
(D) Specimen part of clear series (similar labels), first specimen as in (A)
(E) Specimens part of clear series (mixed labels), first specimen as in (A)
(F) Specimen in unit tray or mixed group of specimens determined (A-D)
(G) Specimen in labeled unit tray - determinor assumed (e.g., personal collection)
(H) Specimen in labeled unit tray - determinor unknown

     Multiple determinations for a single specimen are recorded in our database.  In these cases, one of the determinations (generally the most recent) is considered the accepted determination, which is the determination that we've chosen to adopt and therefore reflects where in OSAC's collection the specimen resides.  It's also possible (and common) for two determination labels to bear different 'BIOLOGICAL NAMES', yet still (given changes in nomenclature, i.e., synonymy) refer to the very same species.  

     Type specimens are the closest thing zoologists have to 'objectively identified' sspecimens.  Type specimens are the specimens that were used by a zoologist(s) who described and named the species to which they now belong.  One type specimen is generally singled out and called the holotype.  The holotype is the definitional standard for the name -- and as such it is (by definition) correctly identified.  Other type specimens (e.g., paratypes, allotypes, etc.) do not hold the same 'definitional' stature, but because they were identified by the original author of the species at the very same time as the holotype - their identity is generally treated with extremely high confidence. In some cases, a 'holotype' does not exist, in which case often a lectotype or neotype has been designated as a replacement.

*Botanists don't commonly use the term determination, but rather annotation for the names placed on specimens in a Herbarium.