What is connectivity and where to find it?

Our world, everything in it, on it, and beyond, is a system with numerous components. Each of those components is a system on its own, except for the smallest known parts of which our universe consists. In complex systems like cells, the human brain, societies, infrastructure, computers, or the universe, the individual components are connected, form networks and interact which each other. Connectivity in such complex systems therefore describes the amount, relation and intensity of the connections within those networks.

So, basically, networks and connectivity are everywhere, and hence there is no discipline or field that does not deal with connections between and within their research objects. Archaeology is no exception, and geoarchaeology in particular focuses on human-environment interactions in past socio-ecological systems.

 

Structural and functional connectivity

Connectivity in complex systems can be divided into two main concepts: Structural and functional connectivity. Structural connectivity (SC) addresses the physical environment and how the individual units are linked to one another, whereas functional connectivity (FC) represents the emergent properties of the system – both influence each other on various spatial and temporal scales. Investigating those two forms of connectivity, their impact on each other and on the system helps us to understand the non-linear dynamics of a system and thus how it functions and behaves.

In geoarchaeology, connectivity mainly refers to landscape connectivity, and especially in my project, it can be described as the extent to which movement is possible in a specific landscape. Structural landscape connectivity represents therefore the physical landscape, and functional landscape connectivity encompasses the emergent dynamic human movements in the landscape. The physical landscape characteristics impact the human’s ability to move in it and at the same time, the movements of the humans change the landscape.

 

Ancient route systems – only a matter of the past?

Route systems can be seen as the physical manifestation (SC) of human movement (FC). Roads show us how, where, and how much people move through a landscape. Based on the route systems of a society, it is possible to reconstruct to some degree its functional connectivity. But unlike our modern roads and infrastructure, ancient movement left no or only sparse traces in the landscape that are still visible today. Prehistoric routes were usually not paved and have been buried in later periods or destroyed by natural or anthropogenic processes like erosion or agriculture. Therefore, we try to model the ancient movement with the information we gather from the archaeological record as well as ethnographic and modern analogues.

 

Satellite image (CORONA satellite images, 1968) of the Bronze Age settlement Tell Brak, Syria. The remains of ancient routes, so-called hollow ways, are radiating from the round settlement mound (red). Tell Brak’s routes are part of a hollow way system of over 6000 km which is rather unique globally.

 

Modelling ancient movement is not only a way to investigate past societies, but it can also help us to tackle current problems. If we can evaluate how connectivity changed and impacted past communities, we may use this knowledge to better understand our modern world. Did connectivity help ancient human systems to be resilient to disturbances like climate change or diseases? Is more connectivity always better or does it at some point have the contrary effect, i.e., make a society more vulnerable? Are there different strategies of connectivity, and if so, which one is the best?

Those are questions I hope to answer within my i-CONN project, and I hope you are as keen as I am to see how I will do that. In that case – keep checking my blog and I will update you on my methods, progress and results!

Take care,

Deborah

 

 

References:

  • Bar-Yam, Y. (1997), Dynamics of Complex Systems, Studies in Nonlinearity.
  • Janssen, M. A., Bodin, Ö., Anderies, J. M., Elmqvist, T., Ernstson, H., McAllister, R. R. J., Olsson, P. and Ryan, P. (2006), ‘Toward a Network Perspective of the Study of Resilience in Social-Ecological Systems’, Ecology and Society 11(1): 15.
  • Kempf, M. (2020), ‘From landscape affordances to landscape connectivity: Contextualizing an archaeology of human ecology’, Archaeological and Anthropological Sciences 12(8): 174.
  • Kindlmann, P. and Burel, F. (2008), ‘Connectivity measures: A review’, Landscape Ecology 23(8), 879–890.
  • Nunes, J. P., Bielders, C. L., Darboux, F., Fiener, P., Finger, D. and Turnbull, L. (2018), ‘Better models are more effectively connected models’, Earth Surface Processes and Landforms 43(6), 1355–1360.
  • Taylor, P. D., Fahrig, L., Henein, K. and Merriam, G. (1993), ‘Connectivity Is a Vital Element of Landscape Structure’, Oikos 68(3), 571–573.
  • Taylor, P. D., Fahrig, L. and With, K. A. (2006), Landscape connectivity: A return to the basics, in R. Crooks and M. Sanjayan, eds, ‘Connectivity Conservation’, Cambridge University Press, Cambridge, pp. 29–43.
  • Turnbull, L., Hütt, M.-T., Ioannides, A. A., Kininmonth, S., Poeppl, R., Tockner, K., Bracken, L. J., Keesstra, S., Liu, L., Masselink, R. and Parsons, A. J. (2018), ‘Connectivity and complex systems: Learning from a multi-disciplinary perspective’, Applied Network Science, 3, p. 11.
  • Wainwright, J., Turnbull, L., Ibrahim, T. G., Lexartza-Artza, I., Thornton, S. F. and Brazier, R. E. (2011), ‘Linking environmental régimes, space and time: Interpretations of structural and functional connectivity’, Geomorphology 126(3-4), 387–404.