Darwin Core Concept List

This document lists the proposed concepts of the DarwinCore version 1.4. This document is meant to serve as a conceptual base that can be extended to meet the needs of more specialized communities. The latest Curatorial and Geospatial extensions, in particular, were designed to complement this document to meet the most basic needs of biological collections. Additional extensions are being developed to meet the needs of botany, paleontology, culture collections, and observational data. The XML schema is not yet recommended for production deployment (until the standard is ratified), only for testing and evaluation. See remarks on the Versions page concerning version history of the Darwin Core. See the Design and Purpose page to understand the philosophy behind the construction of the Darwin Core and its extensions and the inclusions or exclusion of concepts in them.

This is not the normative representation of the draft standard. In the case of any conflict between the two representations, the protocol-independent XML schema takes precedence.

Element	Description	Nillable	Type	Min Value	Max Value
	Record-level Elements
GlobalUniqueIdentifier	A Uniform Resource Name (URN) as a unique identifier for the specimen or observation record. In the absence of a persistent global unique identifier, construct one in the form: “[InstitutionCode]:[CollectionCode]: [CatalogNumber]” Examples: 1) urn:lsid:nhm.ku.edu:Herps:32 2) “FMNH:Mammal:145732”	no	string
DateLastModified	The last date-time of publication when any of the data for the record were modified from the previous publication of that record. When publishing a record for the first time, use the publication date-time. Returns values as ISO 8601 date and time. (cf. http://www.w3.org/TR/xmlschema-2/#isoformats and http://www.iso.org/iso/en/prods-services/popstds/dateandtime.html Example: November 5, 1994, 8:15:30 am, US Eastern Standard Time” would be “1994-11-05T13:15:30Z”	no	dateTime
BasisOfRecord	A descriptive term indicating whether the record represents an object or observation. Examples: PreservedSpecimen- A physical object representing one or more organisms, part of organism, or artifact of an organism. synonyms: voucher, collection, lot. FossilSpecimen- A physical object representing one or more fossil organisms, part of fossil organism, or artifact of a fossil organism. LivingSpecimen- An organism removed from its natural occurrence and now living in captivity or cultivation. HumanObservation- A report by a known observer that an organism was present at the place and time. MachineObservation- A report by a monitoring device that an organism was present at the place and time. StillImage- An photograph, drawing, painting. MovingImage- A sequence of still images taken at regular intervals and intended to be played back as a moving image; may include sound. SoundRecording- An audio recording. OtherSpecimen- Any type of specimen not covered by any of the categories above.	no	string
InstitutionCode	The code (or acronym) identifying the institution administering the collection in which the organism record is cataloged. No global registry exists for institutional codes; use the code that is "standard" at your institution or in your discipline.	no	string
CollectionCode	The code (or acronym) identifying the collection within the institution in which the organism record is cataloged.	no	string
CatalogNumber	The alphanumeric value identifying a record within the collection. It is highly recommended that each record be uniquely identified within a collection by this value. It is also recommended that each record be uniquely identified in a global context by the combination of InstitutionCode, CollectionCode and CatalogNumber.	no	string
InformationWithheld	Brief descriptions of additional information that may exist, but that has not been made public. Information about obtaining the withheld information should be sought from the administrative contact identified in the provider resource metadata (curator, collection manager). Examples: "specific locality information given only to nearest county", "ask about tissue samples", "georeferences given only to nearest degree".	yes	string
Remarks	Free text comments accompanying the object or observation record.	yes	string
	Taxonomic Elements
ScientificName	The full name of the lowest level taxon to which the organism has been identified in the most recent accepted determination, specified as precisely as possible, including name-author, year or authorship, sensu or sec. (according to or following) author, and indication of uncertainty. Conceptually equivalent to a full taxonomic identification as given by the identifier (verbatim). Does not include the identifier name or date of identification. Examples: "Coleoptera" (an Order), "Vespertilionidae" (a Family), "Manis" (a Genus), "Ctenomys sociabilis" (Genus + SpecificEpithet), "Ambystoma tigrinum diaboli" (Genus + SpecificEpithet + SubspecificEpithet), "Quercus agrifolia var. oxyadenia (Torr.) J.T. Howell" (Genus + SpecificEpithet + InfraspecificRank + InfraspecificEpithet + AuthorYearOfScientificName).	no	string
HigherTaxon	The names of taxonomic ranks less specific than SpecificEpithet concatenated and separated. "LIKE" or "contains" substring query operations are meant to be used with this element to find matching higher taxon names. This element may contain the list of scientific names of all of the supra-specific taxa in the classification used to identify (determine) the specimen or observation. Example: "Animalia, Chordata, Vertebrata, Mammalia, Theria, Eutheria, Rodentia, Hystricognatha, Hystricognathi, Ctenomyidae, Ctenomyini, Ctenomys".	yes	string
Kingdom	The name of the kingdom in which the organism is classified.	yes	string
Phylum	The name of the phylum (or division) in which the organism is classified.	yes	string
Class	The name of the class in which the organism is classified.	yes	string
Order	The name of the order in which the organism is classified.	yes	string
Family	The name of the family in which the organism is classified.	yes	string
Genus	The name of the genus in which the organism is classified.	yes	string
SpecificEpithet	The specific epithet of the scientific name applied to the organism.	yes	string
InfraspecificRank	The infraspecific rank (subspecies, variety, forma) of the InfraspecificEpithet. Examples: "subsp.", "var.", "forma".	yes	string
InfraspecificEpithet	The infraspecific epithet of the scientific name applied to the organism.	yes	string
AuthorYearOfScientificName	The author of the ScientificName and the year of publication, if known. More than one author can be listed in a concatenated string. Should be formatted with parentheses and year according to the conventions of the applicable NomenclaturalCode.	yes	string
NomenclaturalCode	The nomenclatural code under which the ScientificName is constructed. Examples: "ICBN", "ICZN", "BC", "ICNCP", "BioCode"	yes	string
	Identification Elements
IdentificationQualifer	A brief phrase or a standard term ("cf.", "aff.") to qualify the identification of the organism when doubts have arisen as to its taxonomic identity (determination). Examples: 1) For the determination "Quercus aff. agrifolia var. oxyadenia", IdentificationQualifier would be "aff. agrifolia var. oxyadenia" with accompanying values "Quercus" in Genus, "agrifolia" in SpecificEpithet, "oxyadenia" in InfraspecificEpithet, and "var." in InfraspecificRank. 2) For the determination "Quercus agrifolia cf. var. oxyadenia", IdentificationQualifier would be "cf. var. oxyadenia " with accompanying values "Quercus" in Genus, "agrifolia" in SpecificEpithet, "oxyadenia" in InfraspecificEpithet, and "var." in InfraspecificRank.	yes	string
	Locality Elements
HigherGeography	The names (concatenated and separated) of geographic elements less specific than the information in the Locality element. "LIKE" or "contains" substring query operations are meant to be used with this element to find matching geographic names. This can be useful if it is unclear in which element a name might be found, and in cases where there is no other appropriate geographic element. Example: "South America, Argentina, Patagonia, Parque Nacional Nahuel Huapi, Neuquén, Los Lagos" with accompanying values "South America" in Continent, "Argentina" in Country, "Neuquén" in StateProvince, and Los Lagos in County.	yes	string
Continent	The full, unabbreviated name of the continent on which the organism was collected or observed.	yes	string
WaterBody	The full, unabbreviated name of the body of water in or over which the organism was collected or observed.	yes	string
IslandGroup	The full, unabbreviated name of the island group in which the organism was collected or observed.	yes	string
Island	The full, unabbreviated name of the island on which the organism was collected or observed.	yes	string
Country	The full, unabbreviated name of the country or major political unit in which the organism was collected or observed.	yes	string
StateProvince	The full, unabbreviated name of the state, province, or region (i.e., the next smaller political region than Country) in which the organism was collected or observed.	yes	string
County	The full, unabbreviated name of the county, shire, or municipality (i.e., the next smaller political region than StateProvince) in which the organism was collected or observed.	yes	string
Locality	The specific natural language description of the place where the organism was collected or observed. This element need not contain less specific geographic information provided in other geographic elements (HigherGeography, Continent, Country, StateProvince, County, WaterBody, Island, IslandGroup). Though coordinate information can be contained in this concept, these data will be usable analytically only when shared through the concepts of the Geospatial Extension.	yes	string
MinimumElevationInMeters	The minimum or actual elevation at which the collection or observation was made. Use negative values for locations below sea level. Examples: 75 (for an elevation of 100 +- 25 meters). 100 (for an elevation between 100m and 200m).	yes	double
MaximumElevationInMeters	The maximum or actual elevation at which the collection or observation was made. Use negative values for locations below sea level. Examples: Examples: 125 (for an elevation of 100 +- 25 meters). 200 (for an elevation between 100m and 200m).	yes	double
MinimumDepthInMeters	The minimum or actual depth at which the collection or observation was made. Use positive values for locations below the surface. Examples: 0 (for a depth of up to 10m). 50 (for a depth between 50m and 100m).	yes	double
MaximumDepthInMeters	The maximum or actual depth at which the collection or observation was made. Use positive values for locations below the surface. Examples: 10 (for a depth of up to 10m). 100 (for a depth between 50m and 100m).	yes	double
	Collecting Event Elements
CollectingMethod	The name of, reference to, or brief description of the method or protocol under which the collecting event occurred. Examples: "UV light trap", "mist net", "bottom trawl".	yes	string
ValidDistributionFlag	A flag ("true" or "false") that indicates whether the locality information represents a valid distribution occurrence for a specimen. Specimens taken from captivity and showing the captive location should use the value "false".	yes	boolean
EarliestDateCollected	The earliest date-time (Common Era calendar) in a date-time period during which an organism or group of organisms was collected or observed. If the event is recorded as occurring at a single date-time, populate both EarliestDateCollected and LatestDateCollected with the same value.	yes	DateTimeISO
LatestDateCollected	The latest date-time (Common Era calendar) in a date-time period during which an organism or group of organisms was collected or observed. If the event is recorded as occurring at a single date-time, populate both EarliestDateCollected and LatestDateCollected with the same value.	yes	DateTimeISO
DayOfYear	The ordinal day of the year on which the object or observation was collected (1 for January 1, 365 for December 31, except in a leap year, in which case it is 366). If the EarliestDateCollected and LatestDateCollected do not occur on the same day, do not populate DayOfYear.	yes	integer	1	366
Collector	The name(s) (concatenated and separated) of collectors or observers. "LIKE" or "contains" substring query operations are meant to be used with this element to find matching collector names. The primary collector or observer, especially one whose CollectorNumber is also provided, should be listed first. Example: "Oliver P. Pearson, Anita K. Pearson" where the value in CollectorNumber "OPP 7101" corresponds to the number for the specimen in the field catalog (collector number) of Oliver P. Pearson.	yes	string
	Biological Elements
Sex	The sex of the biological individual represented by the cataloged object or observation. Examples: "male", "female", "hermaphrodite", "gynandromorph", "monoecious", "dioecious", "not recorded", "indeterminate", "transitional".	yes	string
LifeStage	The age class or life stage of the biological individual represented by the catalogued object or observation. Examples: "adult", "mature", "juvenile", "eft", "nymph", "seedling", "seed", "egg"	yes	string
Attributes	List of additional measurements or characteristics (concatenated and separated) for which there is no existing semantic element, but which the data provider nevertheless feels the desire to share. Examples: "Tragus length: 14mm; Weight: 120g", "Height: 1-1.5 meters tall; flowers yellow; uncommon".	yes	string
	References Elements
ImageURL	A Universal Resource Locator reference to digital images associated with the specimen or observation.	yes	anyURL
RelatedInformation	Free text references to information not delivered via the conceptual schema, including URLs to specimen details, publications, bibliographic references, etc.	yes	string

Status:

• Proposed TDWG Standard, submitted for consideration as a full standard.

• Not for use in production systems.

• The discussion is on-going and this documentation will continue to be updated to reflect the evolving consensus.

Submitted by: Stan Blum, John Wieczorek

Submitted: 10 Jul 2005

Open Questions:

• 8 Oct 2004 - AssociatedSpecies element requested. (Cooper, GBIF Circa).

• 3 Sep 2005 - Recommendation that MaNIS, OBIS, and BMDE all use Darwin Core 2 with extensions rather than extending DwC2 in new schemas (Wieczorek).

Comments

Use the space below to make comments about this page. -- JohnWieczorek - 24 Aug 2006

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Application behaviour Posted by vieglais at 2004-08-31 10:50 AM

The comment that applications will behave unpredictably is not really correct. It is correct to say that without appropriate guidelines, then unpredictable behaviour will appear. The question is whether those guidelines are defined in the protocol or in the record structure definition external to the protocol.

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associated organism link in darwin Core v2 Posted by Jerry Cooper [mailto:CooperJ@Landcareresearch.co.nz] Date: Friday, 08 Oct 2004, 00:45:48

I'd like to make an urgent plea for the development of an 'associated organisms' extension or core element. Those of you currently in, or heading to, New Zealand will realize that we operate one of the strictest border biosecurity systems in the world, and in addition one of our biggest threats to bidiversity comes from invasive species, and for that reason we carry out much reasearch on biological control. Biosecurity risk analysis and biological control research both require access to global repositories of host/vector/pest/pathogen relationships. Many primary biodiveristy databases include this information for hosts/pollinators/food plants/symbionts/mycorrhizal assocates etc. This simple link to another name (in the same dataset and not through a linked catalogued item - which may not explicitly exist) places a collection/observation record into a valuable ecological context. Please can we have a home for that simple data item?

Jerry Cooper, New Zealand

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DARWIN CORE and Simplicity Posted by deblades at 2005-01-06 11:44 AM

Being a entomological researcher, a database programmer/designer and having worked as an entomolgy collections manager, I find this initiative to be quite exciting. I am just getting familiar with the content of this project and its goals but I see a problem, all too common in these sorts of endeavours, beginning to rear its ugly head - the dreaded SCOPE CREEP!

Looking at the comments posted below the schema (data elements) definition http://darwincore.calacademy.org/Documentation/DarwinCore2DraftHTML [ Note: Migrated to - http://wiki.tdwg.org/twiki/bin/view/DarwinCore/DarwinCoreDraftStandard ], I notice that some folks are asking for rather esoteric data elements be added, elements that really don't contribute information useful in analysis of specimen data. Perhaps the project needs to define a minimal set of data elements required to share the information (e.g. species name, geographic coordinates, sample dates and source collection) and meet the stated project goals:

"The Darwin Core is a specification of data concepts and structure intended to support the retrieval and integration of primary data that documents the occurrence of organisms in space and time and the occurrence of organisms in biological collections."

while allowing for additional, optional data elements to be included if one wishes. The nature and number of these additional elements should be carefully considered before their addition however. Other schemas like ABCD provide extensive data structures for recording additional info on specimens that, while useful to the institution holding the collection, are of little value in analyses by external researchers.

Just my two cents worth - I'd love to hear other's opinions!

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Importing DarwinCore Posted by drew at 2005-02-13 02:15 AM

We have successfully imported DarwinCore into our own taxonomic literature schema: TaxonX v.4.1

http://research.amnh.org/informatics/new_ants

http://research.amnh.org/informatics/ants/xml_marked/N3208_taxonx4_1.xml

I would greatly appreciate comments.

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On the use of repeating elements Posted by dhobern at 2005-03-17 12:56 AM

I agree that there is an issue around our not defining the semantics of repeating elements within a Darwin Core record, and that different processors may handle the situation very differently. It is however important to remember that some of the elements should be repeatable and that this should not be excluded. This can be solved independently of whether or not a containing element is defined, but must not be forgotten.

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Unrestricted text fields Posted by: lapham at 2006-03-20 07:38 AM

Most text fields in DwC are unrestricted, permotting anything to be entered and accepted. This leads to consistencxy problems

One sloution to these consistncy problems is to restrict the field to values in list.

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RareTaxon Posted by: lapham at 2006-06-11 12:358 PM

If we had a RareTaxon yes/no field, folks woauld know what was rare and if somebody got a downloaded what was rare would come with it.

One culd keep full locacity data in the datbase and use the flag field to restict data going to the DwC flat file on your sever linked to DiGIR.

Charlie Lapham

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!IndividualCount?? Posted by: dps at 2006-09-26 06:55 AM

One of the issues with DwC that has never been fully addressed is invertebrate specimens preserved in fluids. As is commonly done, individual catalogs may have variable numbers of individuals or either sex (or immatures). Consequently, a lot of information is lost when curators of these collections attempt to squeeze their data into this format. In the previous draft, "!IndividualCount" at least retained some of this information, but I now see this field has been removed in the current draft. Can someone provide the rationale for this?

David Shorthouse

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IndividualCount Posted by: JohnWieczorek at 2007-01-10 11:55 AM In reply to David's comment, above, the IndividualCount element now resides in the Curatorial Extension to the DarwinCore?. The rationale is that it is an element of curatorial interest, rather than of more general interest.

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IndividualCount Posted by: DavidShorthouse at 2007-01-29 07:27 PM Then, with the same logic, the "Biological Elements" to DwC? should be moved into an extension. As it currently stands, these elements cannot be filled with specimens like spiders or other invertebrates in fluid because there may be variable numbers of adult males, adult females, or immatures of these all with the same catalog number. In other words, one vial will have one catalog number but in that vial could be 6 males, 5 females, and a couple immatures. Because the "Biological Elements" above have explicit element like "Sex", the impression is that this current core may be used to construct phenological charts. With spiders and other inverts in fluid, this phenological construction would be erroneous because it is impossible to record "Sex" like this without creating duplicate CatalogNumbers, which clearly is not accetable.

David Shorthouse