Barbara J. Millsa,1, Jeffery J. Clarkb, Matthew A. Peeplesb, W. R. Haas, Jr.a, John M. Roberts, Jr.c, J. Brett Hillb,d, Deborah L. Huntleyb, Lewis Borcka, Ronald L. Breigere, Aaron Clausetf,g, and M. Steven Shackleyh
Author Affiliations
Edited* by Linda S. Cordell, University of Colorado, Santa Fe, NM, and approved February 26, 2013 (received for review November 15, 2012)
Abstract
The late pre-Hispanic period in the US Southwest (A.D. 1200–1450) was characterized by large-scale demographic changes, including long-distance migration and population aggregation. To reconstruct how these processes reshaped social networks, we compiled a comprehensive artifact database from major sites dating to this interval in the western Southwest. We combine social network analysis with geographic information systems approaches to reconstruct network dynamics over 250 y. We show how social networks were transformed across the region at previously undocumented spatial, temporal, and social scales. Using well-dated decorated ceramics, we track changes in network topology at 50-y intervals to show a dramatic shift in network density and settlement centrality from the northern to the southern Southwest after A.D. 1300. Both obsidian sourcing and ceramic data demonstrate that long-distance network relationships also shifted from north to south after migration. Surprisingly, social distance does not always correlate with spatial distance because of the presence of network relationships spanning long geographic distances. Our research shows how a large network in the southern Southwest grew and then collapsed, whereas networks became more fragmented in the northern Southwest but persisted. The study also illustrates how formal social network analysis may be applied to large-scale databases of material culture to illustrate multigenerational changes in network structure.
archaeology North American Southwest spatial analysis network visualization regional interaction
Footnotes
1To whom correspondence should be addressed. E-mail: bmills@email.arizona.edu.
Author contributions: B.J.M., J.J.C., M.A.P., J.M.R., R.L.B., A.C., and M.S.S. designed research; B.J.M., J.J.C., M.A.P., W.R.H., J.M.R., J.B.H., D.L.H., L.B., and M.S.S. performed research; M.A.P., W.R.H., J.M.R., and J.B.H. contributed new reagents/analytic tools; B.J.M., J.J.C., M.A.P., W.R.H., J.M.R., J.B.H., L.B., and M.S.S. analyzed data; and B.J.M., J.J.C., M.A.P., and J.B.H. wrote the paper.
The authors declare no conflict of interest.
*This Direct Submission article had a prearranged editor.
Data deposition: The Southwest Social Networks database is available through Archaeology Southwest (a nonprofit organization) by application. The database contains sensitive locational information for archaeological sites and is available upon request.
http://www.pnas.org/content/early/2013/03/19/1219966110.short
http://www.pnas.org/content/early/2013/03/19/1219966110.full.pdf+html (Full text pdf requires subscription)
Social networks older than internet: Study
PTI | Mar 31, 2013, 08.00 AM IST
WASHINGTON: Modern-day social networks like Facebook and Twitter may help you stay more connected, but a new study has found that such long-distance networks existed even before the advent of internet.
Researchers studied thousands of ceramic and obsidian artifacts from 1200-1450AD to learn about the growth, collapse and change of social networks in the late pre-Hispanic Southwest.
The study led by University of Arizona anthropologist Barbara Mills, sheds light on the transformation of social networks and shows that people of that period were able to maintain surprisingly long-distance relationships with nothing more than their feet to connect them.
They found that early social networks do not appear to have been as restricted as expected by settlements' physical distance from one another.
Researchers found that similar types of painted pottery were being created and used in villages as far as 250 kilometres apart, suggesting people were maintaining relationships across relatively large geographic expanses.
"They were making, using and discarding very similar kinds of assemblages over these very large spaces, which means that a lot of their daily practises were the same," Mills said.
"That doesn't come about by chance, it has to come about by interaction - the kind of interaction where it's not just a simple exchange but where people are learning how to make and how to use and ultimately discard different kinds of pottery," she said in a statement.
"That really shocked us, this idea that you can have such long distance connections. In the pre-Hispanic Southwest they had no real vehicles, they had no beasts of burden, so they had to share information by walking," she said.
The study is based on analysis of more than 8,00,000 painted ceramic and more than 4,800 obsidian artifacts dating from 1200-1450 AD, uncovered from more than 700 sites in what is now Arizona and western New Mexico.
Researchers found that while a large social network in the southern part of the Southwest grew very large and then collapsed, networks in the northern part of the Southwest became more fragmented but persisted over time.
"Network scientists often talk about how increasingly connected networks become, or the 'small world' effect, but our study shows that this isn't always the case," said Mills.
"Our long-term study shows that there are cycles of growth and collapse in social networks when we look at them over centuries. Highly connected worlds can become highly fragmented," Mills said.
http://timesofindia.indiatimes.com/tech/social-media/Social-networks-older-than-internet-Study/articleshow/19290157.cms