tDAR digital antiquity

32,863 Tree-ring Dates Uploaded to tDAR

This post was written by guest author Kyle Bocinsky.

A database of 32,863 tree-ring dates from across the southwestern United States—the largest and most comprehensive of its kind to date—is now available through tDAR. To build the database, we started with a smaller database gathered by Mike Berry and the Dominguez Anthropological Research Group and added several thousand dates from archaeological projects across the Southwest. All dates were determined by the Laboratory of Tree-Ring Research (LTRR) at the University of Arizona. We also used the state site databases for the Four Corners states—Compass (Colorado), NMCRIS/ARMS (New Mexico), Utah Division of State History, and AZSITE (Arizona)—to assign site locations (UTMs) to each tree-ring date.

In an associated research publication—Exploration and exploitation in the macrohistory of the pre-Hispanic Pueblo Southwest (Bocinsky et al. 2016)—my colleagues Tim Kohler, Keith Kintigh, Johnathan Rush, and I analyzed these data for macroscalar patterns, and noted a four-peaked pattern in the number of tree-ring dates through time first established by Mike Berry in the 1980s. These four peaks correspond closely to the widely recognized Pecos classification of Ancestral Pueblo cultural phases. We then compared the tree-ring date distribution to a high-resolution reconstruction of the direct-precipitation maize farming niche across the Southwest from AD 500–1400. We argue that each of the Pecos periods initially incorporates an “exploration” phase, followed by a phase of “exploitation” of niches that are simultaneously ecological, cultural, and organizational. Exploitation phases characterized by demographic expansion and aggregation ended with climatically driven downturns in agricultural favorability, undermining important bases for social consensus. Exploration phases were times of socio-ecological niche discovery and development.

In the research paper, we only use the tree-ring dates from AD 500–1400 (29,311 dates), but we include the comprehensive database in tDAR. We’ve posted two versions of the database: one without site locations that is available to any registered tDAR user, and another available only to those who request permission from Tim Kohler or myself. The database contains site numbers and site names, lab (LTRR) numbers, references where available, the outer date (AD), the outer symbol, and the confidence level. To obtain access to the confidential version with site locations, you must demonstrate that you have permission from the managers of the statewide site files in the four states: Compass (Colorado), NMCRIS/ARMS (New Mexico), Utah Division of State History, and AZSITE (Arizona).

We hope that people find this database useful, and we intend for it to be expanded in the future!



Bocinsky, R. Kyle, Johnathan Rush, Keith W. Kintigh, Timothy A. Kohler, Exploration and exploitation in the macrohistory of the pre-Hispanic Pueblo Southwest, Science Advances 2, e1501532 (2016).

Berry, Michael S., Time, Space, and Transition in Anasazi Prehistory (University of Utah Press, Salt Lake City, Utah, 1982).

Upload your SAA Poster or Paper

SAA tDAR Abstract Project

Once again Digital Antiquity has partnered with The Society for American Archaeology to preserve the meeting abstracts and make the presentations and data used to support them available in tDAR.  As a presenter you can access your record in tDAR, edit the metadata, and upload a PDF copy of your paper, presentation, poster, or other supplementary data (up to 3 files/30MB).  The project is now live in tDAR!  Here’s how to get started:

Find your Abstract

Enter your last name, or the title of your 2015 or 2016 SAA Poster or Paper

  1. Search for your abstract.
  2. Request access (will require a free registration).
  3. Once completed, we will send you a message with a link to edit the abstract and upload the record.
  4. Scroll down and edit or enhance any of the metdata you would like.  Click on the green “add files” button under “Attach Document Files” and follow the prompt to upload a PDF copy of your paper or poster.  If you’d like to upload a dataset in addition to your paper or presentation, please contact us for a voucher. If you are adding multiple files (e.g. your paper, a copy of your presentation, and a dataset) you will probably want to create a project.
  5. You may save your work at any point along the way, but when your edits are complete, make sure to change your resource’s status from “draft” to “active”.
  6. Click save and you are done!
  7. As always, please call or email Leigh Anne at (480) 965-1593 or with any questions along the way!

Were you a presenter in 2015 (San Francisco) but haven’t uploaded your presentation yet?  Not to worry–those abstracts are also in tDAR and can be found in the search bar at the top of this page too.  Help other researchers find and cite your SAA presentations by making them available today!

And SAA Student Members don’t forget that you are eligible to upload 3 files to tDAR annually as part of your membership benefits!  Email to receive your voucher.

Come visit us at SAA 2016

Learn more about tDAR and the Center for Digital Antiquity.

Wednesday April 6th, 2016

Student Welcome Reception, Hosted by SAA Board of Directors and Student Affairs Committee, Co-sponsored by the Center for Digital Antiquity
9:00-10:30 PM – Northern Hemisphere E1-E4

Thursday April 7th, 2016

Poster Session: “Methodologies for Integrating Eastern Archaic Faunal Databases Using the Digital Archaeological Record (tDAR)”
8:00-10:00 AM – Atlantic Hall B
Adam Brin and Leigh Anne Ellison – “Beyond Archiving: Synthesizing Data with tDAR,” Location 9-a

Symposium: “Public Engagement and Education: Developing Heritage Stewardship”
8:00-10:00 AM – Oceanic 3
Jodi Reeves Flores and Leigh Anne Ellison – “Heritage Stewardship in the Digital Age,” 9:30AM

Poster Session: “Heritage Values in Contemporary Society,” Sponsored by the SAA Poster Submission Task Force

8:00-10:00 AM – Atlantic Hall B
Francis McManamon and Jodi Flores – “Heritage in the Digital Age: Guidelines for Preserving and Sharing Heritage with Digital Techniques,”

Saturday April 9th, 2016

Forum: “For the Record: Archaeological Archives in the 21st Century,” Sponsored by Committee for Museums, Collections, and Curation
8:00-10:00 AM – Oceanic 4
Francis McManamon, Discussant

Symposium: What Do We Mean by “Digital Curation?”
1:00-4:00 PM – Asia 4

Leigh Anne Ellison and Adam Brin – “tDAR (the Digital Archaeological Record): A Domain Repository for Archaeology, 1:30PM

Colleen Strawhacker, Thomas McGovern, Emily Lethbridge, Gisli Palsson and Adam Brin – “Linking Transdisciplinary Data to Study the Long-Term Human Ecodynamics of the North Atlantic: The cyberNABO Project,” 2:00PM

Kyle Bocinsky and Adam Brin – SKOPE: Bringing Continent-scale, Local Paleoenvironmental Data to Researchers and the Public, 3:45PM








Upcoming Funding Possibilities for Digital Archiving Projects


There are a few funding opportunities with deadlines this spring that we’d like to share with you.

Cultural Resource Fund Phase II Grants, Due February 15th

The Federal Communications Commission and seven Class I freight rail have created the Cultural Resource Fund to support Tribal and State cultural and historic preservation projects.  You must be among the eligible tribes or States to apply (see here for eligibility).   Fifty competitive grants of up to $50,000 are available during the Phase II funding cycle.  Phase III funding will be announced later this spring.

Council on Library and Information Resources Digitizing Hidden Special Collections and Archives, Initial Proposals Due April 4th

CLIR Hidden Collections grants are designed to fund programs that digitize and provide access to non-digital collections of rare or unique content in cultural heritage institutions.  Funding for projects ranges from $50,000-$500,000 (and the maximum depends on whether you apply as a single institution or as part of a collaborative project).

The National Historical Publications and Records Commission Access to Historical Records, Draft Due April 4th  

The National Historical Publications and Records Commission of the National Archives seeks proposals that promote the preservation and use of historical records collections to broaden understanding of our democracy, history, and culture. This grant program is designed to support archival repositories in preserving and processing primary source materials. The program emphasizes the creation of online tools that facilitate the public discovery of historical records.  Grant funding is available for up to 14 projects of up to $200,000.

If you or your organization is interested in partnering with Digital Antiquity or including tDAR in your proposal please get in touch with us.  We are available to assist with budget development and are interested in potential collaborative projects related to digital preservation of archaeological information.  Please contact us at to discuss your project today!

Taking a look back at 2015

We had a busy year in 2015, tDAR continued to grow with significant contributions from the North Atlantic Biocultural Organization , US Air Force, and US Army Corps of Engineers. tDAR had two major software releases, Munsell and Neolithic which completely redesigned the Data Integration interface to make it easier to use, expanded access to usage statistics, and updated the visualization and mapping interfaces for tDAR.

We are continuing our work, begun in earnest last fall with the Corps of Engineers and the US Air Force on digital archaeological archives for their bases and other facilities. We are also still working with the Phoenix Area Office of the Bureau of Reclamation and Midwest Archeological Center of the National Park Service on their rich archives of archaeological material.

As part of our continuing agreements with Archaeological Institute of America (AIA) and Society for American Archaeology (SAA), we ran workshops highlighting best practices in digital curation at the annual meetings for SAA and AIA in San Francisco and New Orleans respectively. We also continue to provide student members with a number of no cost uploads for contributing their data to tDAR as part of our agreement with SAA.

Content added to tDAR in 2015



Usage Statistics

While we do not maintain detailed statistics on users or use to protect user and contributor privacy, we can share some interesting aggregate data. Below are the most frequently viewed and downloaded resources.

Resources (most viewed)

Resources (most Downloaded)

New Resources in tDAR

We recently made a change to the way we share new resources in tDAR.  In the past, our Twitter account announced each new resource as it was made live.  Moving forward, we’ll do a weekly round-up and let you know what new resources were added to tDAR during the previous week, with a link to a collection in tDAR where the enthusiastic user can see them all!  Our weekly post will attempt to highlight the breadth of new materials by featuring a few of the newest resources.  

This week’s post will play catch up and cover all the resources made active in tDAR over the last month. There is a wonderful variety represented in this group!  For example, there is a new set of photographs of Norse artifacts from Skútustaðir, including several pipe stem fragments and a die.  The Mimbres Pottery Images Digital Database also added more images last month, such as this Style III bowl.  The Eastern Faunal Working Group made available several new coding sheets and ontologies from the Modoc Rock Shelter Site 1980 excavations as part of their efforts to bring together regional faunal data for synthetic analysis.  Coding sheets and ontologies are used alongside data sets to synthesize raw data using tDAR’s data integration tool. There are also a few new resources from Quantico Marine Corps Base.  If you are interested in the history and use of the base you might find this resource a worthwhile read.  Finally, a paper and data related to gender equity in archaeology are now available!  

To see all the resources made active in tDAR for the period 11/02 to 12/11 click here.  

tDAR Software Update (Neolithic)

Digital Antiquity is pleased to announce the 14th major release of tDAR named Neolithic. This release focuses on three major areas of the repository: (1) visualization, (2) maps and spatial data, and (3) modularization and infrastructure work. In addition, the development team has improved performance and reliability as well as making a series of smaller enhancements.


We have redesigned many of tDAR’s graphs and visualizations to be more interactive and appealing. Of note, in the world map which can now be explored and shows break-downs of the different resource-types by country. The graphs on the “explore” page have also be enhanced. Finally, the ontology browser has been updated to better display larger ontologies.

Screen Shot 2015-10-30 at 5.37.27 PM


We’ve improved the underlying mapping libraries used in tDAR. These enhancements allow us to cluster mapped search results, improving the interface. We’ve also updated the maps on the resource pages and improved the creation and management of bounding boxes on the resource edit screen.
Screen Shot 2015-10-30 at 5.43.43 PM

Digital Curator Job Opening at Digital Antiquity

The Center for Digital Antiquity has a new Digital Curator position open and we invite qualified applicants to apply. The position of Digital Curator plays a vital role within our organization. Not limited to one specific function, we seek a well-organized, knowledgeable person who will provide services to clients, including drafting administrative and substantive metadata for digital files to be deposited in tDAR, recommending and carrying out redaction for confidential or sensitive data in files, assisting in the planning of digital collections within tDAR for clients, and other services. 

This person will also assist in the Center for Digital Antiquity’s development, improvement and maintenance of tDAR digital repository. This will involve work on project documentation, cleaning up existing data and entering new data/documents. Digital curators are also involved in creating instructional text and web pages to improve information for tDAR users.

To learn more and to apply, visit the Arizona State University employment website. Applications will be accepted through September 15, 2015.

Dr. Paul R. Green is recognized for outstanding Cultural Resource Management service

Congratulations to our colleague, Dr. Paul Green, Cultural Resources Specialist for the East Region Support Team (RST), part of the U.S. Air Force Civil Engineer Center.  The Secretary of Defense has recognized Paul’s excellent professional work with the 2015 Department of Defense Cultural Resources Management award.

At Digital Antiquity we are particularly happy to learn of this award and that one of the many major accomplishments for which his service is recognized involved a program that we have had a hand in.  Paul had a key role in establishing

“…the first DoD digital cultural resources data archives for permanent curation. Maintained by the non-profit Digital Antiquity, the solution outsources the complex effort of keeping with technological changes in media storage while ensuring DoD cultural data is permanently maintained and easily accessible to authorized users and, as appropriate, the public. (from the announcement of Dr. Green’s award, Cultural Resource Update, the Department of Defense Cultural Resource Program Newsletter [Vol. 11, No. 1, Spring/Summer 2015; p. 5]).

Together with Dr. Jim Wilde, Archaeologist and Cultural Resource Management Subject Matter Expert at the US Air Force Environmental Center, Paul is overseeing the continuing growth of important documents, data, images, and other digital data in tDAR (the Digital Archaeological Record).

More information about the US Air Force digital archive in tDAR is available at:; and

About the Secretary of Defense Environmental Awards program (from the Cultural Resource Update Vol. 11, No. 1, pp. 4-5): Since 1962, the Department of Defense Environmental awards have honored individuals, teams, and installations for their outstanding achievements and innovative work protecting the environment while sustaining mission readiness.  A diverse panel of judges with relevant expertise representing federal and state agencies, academia, and the private sector evaluated all nominees to select one winner for each of the nine categories that cover six subject areas: natural resources conservation; environmental quality; sustainability; environmental restoration; cultural resources management; and environmental excellence in weapon system acquisition.

The Cultural Resources Management award recognizes individuals and teams making significant and lasting contributions to DoD CRM. This award acknowledges efforts to promote cultural resources stewardship in DoD by highlighting outstanding management activities and showcasing DoD’s extensive cultural resources, including archaeological sites, the historic built environment, and cultural landscapes. Desired initiatives include partnering with external stakeholders such as Native Americans, SHPOs, and local communities, and working with internal stakeholders in the areas of master planning, public works, and range management.  More information on the Awards can be found at:

Digital Antiquity Announces per File Price Reductions for Digital Preservation in tDAR!

We’ve got great news! We have reduced prices significantly. As of 14 July 2015, it costs only $10 to upload a single file (up to 10MB) to tDAR. This is a significant decrease compared to the former price of $50 per file.

In recent months, we undertook a careful evaluation of operating costs and reviewed the consistent stream of new tDAR clients and DIY digital preservation customers.  Based on these factors, The Center for Digital Antiquity’s Board of Directors and Arizona State University’s financial administrators approved a significant reduction in price to upload digital content to tDAR for long term access, discoverability, and preservation.

This change will be of interest particularly for contributors who upload small quantities of digital files and create the metadata records on their own. Larger clients also will benefit because the low rate of $5/file now applies for purchases of 100 or more files. Check out the full new price list below or visit our new pricing page.

Digital Preservation


1-99 files*


100+ files


Curation Services


File Checking, Metadata Drafting, Basic Quality Control, etc.


Consulting, Planning, Programming, Management, etc.


*Each tDAR file comes with 10MB of space.  To upload digital resources larger than 10MB simply purchase additional tDAR files.


You can easily purchase exactly the number of files and storage space that you need using our price calculator and your credit card just like before.  Of course, our digital curators, project managers, and technical staff are always happy to work with you on a customized project for an hourly rate as well. 
Digital preservation fees fund the long-term care of files in tDAR; access to public data and protection of confidential information; data security; customer service; and, advocacy and professional training for proper digital curation of all archaeological materials.

tDAR is a domain repository in which data and information about and from archaeological resources, investigations, and related topics. In tDAR, data and information are curated, discoverable, accessible, and preserved for future use.  tDAR is developed and maintained by the Center for Digital Antiquity, a not-for-profit center at Arizona State University.
Our promise to broaden the access to archaeological data and dedication ensuring preservation will continue to thrive with your support!

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