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The Čḯxʷicən Bird Bone Project

A Report on Methods and Descriptive Summary of Identifications and Primary Data Set

Project Abstract

Banner photo credit: Lower Elwha Klallam Tribe on Canoe Journey, 2019, photo used with permission by Keri Ellis and LEKT

Overview

The  Čḯxʷicən site is a Lower Elwha Klallam Tribe (LEKT) village in Port Angeles, WA, U.S.A., at the base of Ediz Hook on the south shore of the Strait of Juan de Fuca that was occupied for the past 2,700 years (Larson 2006). In 2004, Larson Anthropological Archaeological Services (LAAS) and LEKT members excavated the site with large open blocks of 1 x 1 m units by finely defined stratigraphic layers (Reetz et al. 2006). In 2012, Kristine Bovy (University of Rhode Island), Virginia Butler (Portland State University [PSU]), Sarah Campbell (Western Washington University), Michael Etnier (Western Washington University), and Sarah Sterling (PSU) initiated a research project focusing on Čḯxʷicən's faunal remains and geo-archaeological records from the 2004 mitigation. As part of project design, we selected to study excavation areas that were linked to two possible plankhouses, to include interior and extramural deposits.

The Bird Bone Project includes a report on the sample selection and processing decisions, taxonomic and taphonomic summaries, and analysis criteria for taxonomic identifications; and the primary data set generated from the analysis. The Bird Bone Project is part of a larger zooarchaeological-geoarchaeological project, The Čḯxʷicən Project.

You may dynamically explore the data by clicking on "Data Records" at the right side of the screen or download a static CSV file of all 9,419 records in the Čḯxʷicən Bird Bone dataset.


Support

Funding for this project came largely from the National Science Foundation [grant number 1219483].


Definitions/Explanations for Column Headings on Čḯxʷicən Bird Database

By Kristine M. Bovy

Note: These definitions are also available as a downloadable PDF, Čḯxʷicən Bird Bone Project: Methods, Analytical Protocols, and Descriptive Summary for the 2012-2019 Analysis.

Bird_IDNum

Bird Identification Number—this is a unique identifier for this specific row/line. Note that each row/line may represent multiple specimens (see ‘Quant_Bird’ below).

Catalog Number

Catalog numbers match the artifact and faunal specimen inventory maintained by the Burke Museum. Catalog numbers take one of two basic formats depending on whether they were collected in situ during the excavations or if they were collected in the water screens.

Most samples included in our 2012-2019 project were collected from water screens and are designated as ‘WS’ (e.g., ‘water screen’) catalog numbers. Because of various issues (see Butler et al., 2018), the project team re-screened all the water-screened samples in our study. This process led us to create a slightly revised catalog system (from the original LAAS/Burke Catalog) with FOUR sub-numbers.

WS-16788.99.04.21

The number after the WS- is the ‘bag number’ (see ‘Bag Number’ below), which is the number assigned by LAAS lab/field personnel (Kaehler and Lewarch, 2006) with numbers assigned in the order in which the Unit/Level bags were added to the Master Catalog. The bag number can range from one to five digits. The ‘99’ after the bag number specifies that this sample was re-screened by the 2012-2019 project.

The ‘04’ in the example above designates the screen size fraction for that particular entry (here, ¼ -inch). Screen size designations are as follows:

01 1-inch

02 ½ -inch

04 ¼ -inch

08 ⅛ -inch

99 <⅛ -inch

The final sub-number (‘21’ in the example above) specifies the main animal type to which the sample belongs. Those categories are:

10 Invertebrate

20 Unidentified Vertebrate (non-fish)

21 Mammals

22 Birds

23 Fish

Samples collected in situ, termed ‘E’ samples (see ‘Bag Type’ and ‘Analytical Bag Type’ below), maintain their original Master Catalog number from the LAAS/Burke Museum. The numbering system begins with the excavation area/block designation (Area A4 in the following example):

A4-197.01.01

The number after the dash (197) refers to the Field Bag number, which can be matched to bag numbers listed in the Unit/Level records (Kaehler and Lewarch, 2006). Explanations for the two sub-numbers after the Bag Number are described in Appendix 5 of the LAAS report (Larson, 2006, Appendix 5: pg 4)

BagNumber

This is the first number of the Catalog Number (see above), which is the number assigned by LAAS lab/field personnel (Kaehler and Lewarch, 2006) with numbers assigned in the order in which the Unit/Level bags were added to the Master Catalog. This is the original bag number as it appears in the LAAS/Burke Museum catalog.

Analytic_BagNum

In most situations, ‘Analytic_Bag Number’ and ‘BagNumber’ are the same. However, as explained by Butler et al. (2018), we encountered situations where it appeared that constituents from a single original field bag/bucket were split into >1 Bag Numbers during laboratory processing. Butler et al. (2018) explain how this was deduced. The Analytic Bag number is the team’s best identification for the complete, 10 L water-screened bucket that had later been subdivided; and is used when estimating excavation volume for calculations of density/accumulation rate.

Re-screened

This duplicates the sub-number information in the Catalog Number (see above). All of the water-screened samples have the ‘0.99’ code to indicate these were re-screened as part of the 2012-2019 project. The ‘E’ samples—those that were collected in situ during excavation, were not re-screened.

ScreenSize

This duplicates the sub-number information in the Catalog Number (see above). This refers to the mesh size from which the constituents were recovered as noted above.

01 1-inch

02 ½ -inch

04 ¼ -inch

08 ⅛ -inch

99 <⅛ -inch

Screen size was not listed for the ‘E’ samples, as they were collected in situ without screens.

Material Type

This duplicates the sub-number information in the Catalog Number (see above). This number specifies the main animal type. Those categories are:

10 Invertebrate

20 Unidentified Vertebrate (non-fish)

21 Mammals

22 Birds

23 Fish

Area

The terms ‘Area’ or ‘Block’ are used interchangeably in our reporting. The original site report (Larson, 2006) used the term ‘Area’ to define the four massive project areas that were assigned during 2004 field work (Area A, B, C, D) and the term ‘Block’ for the contiguous excavation units excavated in a particular ‘Area’ (e.g., Block A1, A4, B1, etc., where the alpha code refers to ‘Area’ and the number is the excavation ‘Block’ within the Area). However, the Master Catalog (and faunal bag labels) column heading/field the Burke Museum sent us referred to the set of contiguous units as ‘Area’ not Block (e.g., Area A1, A3). For our 2012-2019 project and faunal catalog, we followed the convention used in the Master Catalog. We use Area to refer to the contiguous grouping of excavation units that combines the Area code (A) and the Block number (1, 4, etc.), thus A1, A4. Since most of the NSF project focused on one of the massive Areas (e.g., Area A), the distinction between Area and Block is not critical.

Unit

Unit refers to an excavation unit number (e.g., 1, 2, 3) that was assigned sequentially as an Area/Block was being excavated by LAAS crews (Reetz et al., 2006). The labels listed in ‘unit’ are exactly the code as assigned in the field, in the catalog and on the original faunal bags sent to us. Most units are 1m2. Most unit codes are single whole numbers (e.g., 1, 2, 3), but sometimes the label includes an ‘A’ (e.g., 1A, or other alpha), or sometimes units were joined with slashes (e.g., 2/13, 30/32). Reetz et al. (2006) provides detailed maps that show unit numbers in each Area/Block.

Adjusted_Unit

When the Unit code is a simple number (e.g., 1, 2, 3) the Adjusted Unit label is the same as the Unit code. We created the Adjusted Unit field to recode the unit labels that had an ‘A’ or were aggregate units (e.g., 2/13) so that such units could easily be manipulated in the database. LAAS added the ‘A’ codes to excavation unit labels when field crews returned to excavate units that had previously been dug. Thus, in Area/Block A4, field crews returned to the southern part of the block and dug deeper in units 1, 2, 3, 6, 7, 8, 11, 12, 30, 40 that had previously been partly excavated (see Reetz et al., 2006: 40-36). The ‘A’ code was added to these ‘revisited units’ but the excavation units with or without the ‘A’ are the same unit. The Adjusted Unit code that we created simply assigns the units with the ‘A’ to the original Unit number. What was ‘1A’ in the Unit code becomes ‘1’ in the Adjusted Unit code. In a few cases, mostly involving features that overlap two units, provenience was recorded as both units (e.g., 2/13). In these cases, the adjusted unit is the unit in which the strat was most extensive.

Strat

This is the stratigraphic code assigned in the field based on a variety of geoarchaeological criteria, including relative position in the stratigraphic sequence, composition, color, texture, lithology, etc. (Sterling et al., 2006).

Adjusted_Strat

In most cases, the Adjusted_Strat code is the same as the Strat code. In a very small number of cases, the Adjusted Strat was used to correct data entry errors in the Burke Museum catalog. In other cases, matrix with similar characteristics were designated as two or more strata with a slash convention, e.g. 5.1.3.2/6.5, because of uncertainty about the best match. Unit level records were consulted to resolve this; generally, there were notes about later determinations of the strat, or continuity with adjacent units was the determinant.

Feature

This code refers to the sequential number unique to each Area (e.g., A, B, C, D) assigned to a cultural feature (e.g., hearths, post molds, etc.,) over the course of fieldwork (Reetz et al., 2006).

Level

Designates an arbitrary level within a natural stratum (Reetz et al., 2006). We retained ‘OVB’ for overburden and ‘U’ designating materials recovered from a collapsed wall as per the Burke Museum catalogue. Our project added the code ‘NLR’ to indicate that no level records existed for the sample.

CZ

CZ refers to chrono-stratigraphic or more simply, ‘chronozone’ (CZ). Campbell et al. (2019) defined seven CZs based on use of 59 radiocarbon ages and analysis of depositional sequences of field-identified strata (see table below). Through this process, all unique field-documented strata and associated samples (C, CX, S buckets and in situ E specimens) were assigned to one of the seven CZs, from CZ 1 (2150–1750 cal BP) to CZ 7 (300–150 cal BP). Chronozone 4b (CZ 4b) consisted of material that had been displaced in the past by erosion or house construction; fauna from these samples were not included in the overall analysis.

Chronozone

Age Range (CalBP)

Mid-Point (CalBP)

CZ 7

300–150

225

CZ 6

550–300

425

CZ 5

1000–550

775

CZ 4

1300–1000

1150

CZ 3

1550–1300

1425

CZ 2

1750–1550

1650

CZ 1

2150–1750

1950

The bird database includes material from CZ4b, but excludes any other material that was not included in the final analyses, such as strata not assigned to chronozone because of construction disturbance (e.g., Strat 2.0). See Bovy (2018: Section 2.5: ‘ Partially analyzed’ and excluded material) for more information on this excluded material.

Depositional Context

Depositional context was determined by Campbell following close analysis of matrix characteristics. Deposits associated with house occupation were designated as floor or fill depending on their characteristics (Floor = spongy, dark, compact, horizontal; Fill = loose, structureless, sloping). Floors were numbered sequentially within a house with 1 designating the initial, or lowest floor. Transition Zone designates the area closest to the wall, inside the house, where the stratified floor sequence cannot be traced due to the different depositional processes in that area. The designations Pre-house and Post-house were used only within the footprint of the house. Extramural deposits lie outside of house footprints.

Extramural

Fill

Floor 1

Floor 2

Floor 3

Floor 4

post-house

pre-house

Transition Zone

Bag Type

This code refers to one of three main field sampling methods described by LAAS personnel (Kaehler and Lewarch, 2006) and which appears in the original Master Catalog. Most buckets from a given stratum were screened to ¼″ and called Sample or ‘S’ buckets. Invertebrate shell was not retained from S buckets. A minimum of one bucket was processed from each stratum of each 1 m2 grid unit and screened to ⅛″ mesh. Such buckets were labeled Complete or ‘C’ buckets. Finally, relatively large remains were recorded in situ during excavation and referred to as ‘E’ samples. The codes listed under Bag Type refer to one of these three codes, S, C, or E from the original catalog. The 2012-2019 project team found that about half of the so-called ‘C’ bags were not in fact ‘complete’, but rather were missing ⅛” mesh materials. LAAS protocols changed over the project. Importantly—the Master Catalog did not distinguish such buckets. Both were labelled ‘C’ in the Master Catalog. The project team created a revised coding system to address this issue. See ‘Analytic_Bag Type’ and Butler et al. (2018).

Analytic_Bag Type

For S and E buckets, the code for Bag Type and Analytic Bag type is the same. We created a new code, ‘CX’ to distinguish true ‘C’ buckets (that included matrix >⅛”) from those buckets from which only ¼” mesh and larger were retained. Thus, for Analytic Bag Type, possible codes includeS, E, C (which includes all matrix <⅛”) and CX (which includes only matrix >¼”). While I did analyze some specimens from CX buckets listed from ⅛” matrix (before we understood the ‘C’ and ‘CX’ distinction), I have excluded these from the database because they should not be included in systematic analysis of faunal representation, given lack of control on mesh size. See Bovy (2018: Section 2.5: ‘Partially analyzed’ and excluded material) for more information on this excluded material.

Quant_Bird

The ‘Quant_Bird’ field is either NSP (for all specimens identified as ‘bird’) or NISP (Number of Identified Specimens) for those identified more specifically. Refit specimens were counted as one specimen, and the refit was noted in the ID Comments field. For example, a specimen broken into 3 fragments would be listed as ‘1’ in the Quant_Bird field; in a number of cases, a specimen is listed with a ‘0’ quantity, which means it refits to a specimen with a different catalog number (frequently a different screen size within the same bag).

FaunalCategory

All specimens were either coded as ‘Aves’ or ‘Vertebrate (non-fish).’ This allowed easy sorting of the bird specimens from the unidentifiable fragments, which could be either bird or mammal; see discussion in Bovy (2018: Sec. 3: Bird bone analysis procedures) for more information. Note that with a few exceptions (2 cut marked bones and 1 gnawed bone) the Vertebrate (non-fish) remains are not discussed in the bird bone report (Bovy, 2018), though they are summarized in Bovy et al. (2019). Importantly, the Vertebrate (non-fish) remains that were originally identified as bird, or were later transferred to my lab as possible bird, are listed in the bird database. Therefore, when sorting the bird database, the Vertebrate (non-fish) remains need to be filtered out, if only information on bird remains is desired.

A Note on Taxonomic/Linnaean Hierarchy

In general, I attempted to identify bones/bone fragments to the most specific taxon possible; but see discussions in Bovy (2018: Sec. 3.1:A note on the specificity of the Identifications and Sec. 3.2: A note on the ‘cf.’ identifications) for more guidance on the varying specificity of the identifications. Also, all vertebrae, ribs, and phalanges were identified only as Aves.

Identification was recorded according to the Linnaean hierarchy, using the most recent nomenclature available. Taxonomic names follow the Seventh Edition of the American Ornithologists’ Union (AOU) check-list (1998), as well as the numerous (and often substantial) changes made to the check-list in recent years, which are available as supplements on the AOU website and published in The Auk each year. Genetic studies have altered many earlier assumptions about taxonomic relationships of birds, changing the placement and taxonomic names of many species.

If a particular level of the hierarchy could not be reached, say a specimen could only be identified to the level of Family, all lower fields (Genus and Species, in this example) are left blank. Note that for species-level IDs, only the species epithet is listed in the ‘Species’ field—both the Genus and the Species fields must be combined to extract the Linnaean species.

Finally, the most specific taxonomic level for each specimen is also listed under ‘Finest Taxon’ (see below).

Class

Order

Family

Subfamily (for Anseriformes only)

Tribe (for Anseriformes only)

Genus

Species

Finest Taxon

Finest Taxon refers to the most specific taxonomic classification (e.g., class, order, family, genus, species) to which a specimen can be assigned. This may or may not correspond to a Linnaean taxon. See ‘A Note on Taxonomic/Linnaean Hierarchy’ above. Specimens which could only be assigned to a faunal category are listed here as that category. Thus, specimens which can only be assigned to ‘Bird’ are listed in Finest Taxon as ‘Aves.’ Fragments that could only be securely identified as bone (primarily the ⅛” fraction) were coded as Vertebrate (non-fish); see ‘FaunalCategory’ above and Bovy (2018: Sec 3.) for an explanation of this code.

Element/ Segment/ Side/ Zone

Element refers to the specific skeletal element (e.g., humerus, skull, vertebra, etc.), while Segment denotes a portion of a skeletal element, either a specific name (e.g., pterygoid) or a description (e.g., proximal). If the element was complete, ‘whole’ was entered in the segment field. Avian skeletal part terminology follows Howard (1929). In most cases, the element side (left or right of the body) was also recorded; however, in a relatively few cases the side could not be securely determined, even though the element was identifiable (e.g., ulnae or radii shaft fragments). The Zone field indicates which particular portions/landmarks of the bone were present (e.g., FEM 1 is located at the head of the femur). Bone zone codes are from Serjeantson (2009: Appendix 2), except for mandible and second wing digit (Phalanx 1; see Bovy, 2005: Figure A-1). The side and bone zone were recorded to aid in the calculation of minimum number of elements (MNE), if desired.

Age

A protocol was in place to record the relative age of the bird specimens (Bovy, 2011; Broughton, 2004). ‘Adult’ specimens have developed cortical bone and muscle attachments. ‘Juvenile’ specimens may approach adult size, but lack complete development of cortical bone, and muscle attachments may or may not be present. Finally, ‘chicks’ are small in size, porous, and lack cortical bone and muscle attachments. Only 14 of the Čḯxw icən bird bones appeared to be sub-adult (all ‘juveniles’).

Burn/ Burn Type

The presence/absence (yes or no) of burning was recorded in the ‘Burn’ field. The decision of whether a bone fragment was burnt was made primarily on the basis of color. Three different kinds of burning types were recorded: ‘burnt’ (darkly discolored or blackened), ‘calcined’ (whitish, grayish or bluish), and ‘partially burnt on shaft’ (bones that appeared to have been intentionally heated mid-shaft/element and broken). Because bone specimens showed a wide range of colors that could be interpreted as staining rather than burning, we took a conservative approach to identifying burning and thermal alteration. See Bovy (2018: Sec. 5.1: Burning/heat modification) for more details on burning.

Initial ID

The ‘Initial ID’ field was a way to keep track of bird bones that were initially mis-sorted (by LAAS laboratory staff) as mammal, fish or shell, pulled by Etnier, Butler or Campbell, and later transferred to my lab for analysis.

ID Comments

This field provides additional information on the specimen not already captured in another field, including taxonomic identification notes (e.g., thoughts or impressions on what the likely taxon may be), details about the condition of the bone (e.g., whether the specimen was fragmented or refit), and additional notes on surface modifications. Comments about the catalog # or provenience were also recorded here.

Original ID

In the process of writing this report, I made minor updates to the database to make the finest taxon identifications more standardized (e.g., deleting sizing information if this was not consistently done throughout the analysis). I preserve the earlier identification in this column, since that is the taxonomic name written on the analysis labels on the bags themselves, which had already been returned to the Burke Museum.

Modification

Characteristics such as surface alteration or carnivore damage, and cultural modification were recorded if obviously present. However, specimens have not been systematically examined under a microscope. See Bovy (2018: Sec. 5.: Taphonomic summary) for more information.

Photo

A small number of specimens were photographed to document modifications (especially cut marks, burning and fragmentation) or to aid in analysis. ‘Yes’ was recorded in this field if photos were taken, and a separate excel spreadsheet of all the photos taken was created (on file at the Burke Museum).

References

AOU (American Ornithologist’s Union). 1998. Check-list of North American Birds. 7th edition. American Ornithologist’s Union, Washington, DC. (http://checklist.aou.org)

Bovy, K.M., 2005. Effects of Human Hunting, Climate Change and Tectonic Events on Waterbirds Along the Pacific Northwest Coast During the Late Holocene. University of Washington, Seattle (Ph.D. Dissertation).

Bovy, K.M., 2011. Archaeological evidence for a Double-crested Cormorant ( Phalacrocorax auritus) colony in the Pacific Northwest, USA. Waterbirds 34, 89-95.

Bovy, K.M., 2018. The Čḯxʷicən Bird Bone Project: Methods, Analytic Protocols, and Descriptive Summary for the 2012-2019 Analysis. In The Čḯxʷicən Project. Virginia L Butler, Kristine M Bovy, Sarah K Campbell, Michael A Etnier, Sarah L Sterling (Eds.). Released: 2020-07-21. Open Context https://opencontext.org/media/1fad36bc-21d1-479e-9ee4-e58d31ceedce DOI: https://doi.org/10.6078/M7BC3WNP.

Bovy, K.M., Etnier, M.A., Butler, V.L., Campbell, S.K., 2019. Using bone fragmentation records to investigate coastal human ecodynamics: a case study from Čḯxʷicən (Washington State, USA). Journal of Archaeological Science: Reports 23, 1168-1186. https://doi.org/10.1016/j.jasrep. 2018.08.049.

Broughton, J.M., 2004. Prehistoric Human Impacts on California Birds: Evidence form the Emeryville Shellmound Avifauna. Ornithological Monographs No. 56, The American Ornithologists’ Union, Washington, DC.

Butler, V. L., Bovy, K. M., Campbell, S. K., Etnier, M.A. 2018. Čḯxʷicən Faunal Sample Selection and Processing for the 2012-2019 Analysis. In The Čḯxʷicən Project. Virginia L Butler, Kristine M Bovy, Sarah K Campbell, Michael A Etnier, Sarah L Sterling (Eds.). Released: 2020-07-21. Open Context. https://opencontext.org/media/1fad36bc-21d1-479e-9ee4-e58d31ceedce DOI: https://doi.org/10.6078/M7BC3WNP.

Campbell, S.K., Sterling, S.L., Lewarch, D.E., 2019. Building a landscape history and occupational chronology at Čḯxwicən, a coastal village on the Strait of Juan de Fuca, Washington State, U.S.A. Journal of Archaeological Science: Reports 23, 1104-1130.

Howard, H., 1929. The avifauna of Emeryville Shellmound. University of California Publications in Zoology 32, 301-394.

Kaehler, G., Lewarch,D.E., 2006. Laboratory processing, data entry, and curation. In: L. Larson (Ed.), Final Data Recovery Excavation and Archaeological Monitoring at the Tse-whit-zen Site (45CA523), Clallam County, Washington, Volume 1, Larson Anthropological Archaeological Services Limited, Gig Harbor, Washington. Submitted to Washington State Department of Transportation, Olympia Region, 2-1

Reetz, E.C., Lewarch, D.E., Trudel, S.E., Gillis, N., Kanipe, H.E., Sterling, S.L., Tatum, D.E., Kekkonen, S., 2006. Field techniques. In: Larson, L.L. (Ed.), Final Data Recovery Excavation and Archaeological Monitoring at the Tse-whit-zen Site (45CA523), Clallam County, Washington. Volume 1. Larson Anthropological Archaeological Services Limited, Gig Harbor, Washington. Submitted to Washington State Department of Transportation, Olympia Region, 4-1.

Serjeantson, D., 2009. Birds. Cambridge Manuals in Archaeology. Cambridge University Press, Cambridge.

Sterling, S., Lewarch, D., Tatum, D., Dellert, J., Reetz, E., Trudel, S., Gillis, N., 2006. Stratigraphy and geoarchaeology of the Tse-whit-zen site (45CA523). In: Larson, L. (Ed.), Final Data Recovery Excavation and Archaeological Monitoring at the Tsewhit-zen Site (45CA523), Clallam County, Washington. Volume 1, Larson Anthropological Archaeological Services Limited, Gig Harbor, Washington. Submitted to Washington State Department of Transportation, Olympia Region, 7-1.

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Annotations (3)

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[Standard: Dublin Core Terms]
Is Referenced By
[Standard: Dublin Core Terms]
Čḯxwicən Bird Bone Project: Methods, Analytical Protocols, and Descriptive Summary for the 2012-2019 Analysis
[Standard: Open Context :: The Čḯxʷicən Project]
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Editorial Note

Open Context editors work with data contributors to annotate datasets to shared vocabularies, ontologies, and other standards using 'Linked Open Data' (LOD) methods.

The annotations presented above approximate some of the meaning in this contributed data record to concepts defined in shared standards. These annotations are provided to help make datasets easier to understand and use with other datasets.

Suggested Citation

Kristine M Bovy. "The Čḯxʷicən Bird Bone Project". (2018) In The Čḯxʷicən Project. Virginia L Butler, Kristine M Bovy, Sarah K Campbell, Michael A Etnier, Sarah L Sterling (Eds.) . Released: 2018-12-01. Open Context. <http://opencontext.org/projects/339673ec-f692-4a96-8a88-1e7a3c8ae4fa> DOI: https://doi.org/10.6078/M7TX3CFN

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