NetLogo User Community Models

(back to the NetLogo User Community Models)

Download If clicking does not initiate a download, try right clicking or control clicking and choosing "Save" or "Download".(The run link is disabled because this model uses extensions.)

## WHAT IS IT?

Agent base modelisation of the neolithization process in the Mediterranean area and interactions between autochtonous hunter-gatherers and neolithic settlers.

## HOW IT WORKS

The background map combines an elevation map and a climatic one (made in QGis).

- Elevation map: gtopo1km (https://www.usgs.gov/centers/eros/science/usgs-eros-archive-digital-elevation-global-30-arc-second-elevation-gtopo30?qt-science_center_objects=0#qt-science_center_objects) >
The working area is restricted to -10,42,28,48 frame, and is changed intor a raster with a grid of 0.25° (i.e. ~22km). For each square, the elevation mean is calculated and rounded to the nearest integer. They are the then classified into 5 types: 1=Sub-montane level (z<500 m asl), 2=Mountain level (500≤z<1500 m), 3=Subalpine level (1500≤z<2000 m), 4=Alpine level (2000≤z<2700 m), 5=Eternal snow level (2700≤z).

- Climatic map: extract from RUBEL F., KOTTEK M. (2010) ‒ Observed and projected climate shifts 1901–2100 depicted by world maps of the Köppen-Geiger climate classification, Meteorologische Zeitschrift, 19, 2, p.p. 135‑141 under a 0.25° grid (the original map was with a 0.5° grid). A k indice is subjctively estimated for the agricultural potential.

This pitch of 0.25° of the grid partially compensates partially for the rise in sea level.

These two maps are combined to calculate a kind of agricultural potential coefficient (APC) ; APC = k/Z (k= climatic type; Z = elevation class). The APC for the seas is manually sets to 0.1 (for marine food resources and navigation possibilities). The APC for inland desert is manually sets to 0.02 (no food resources but possible move).

The APC vector map is changed into a raster one and then exported into an ascii file (float32 format) for the integraiton into NetLogo.
From QGis, the header of this file has to be manually changed with the followings:
north: 48N
south: 28N
east: 42E
west: 10W
rows: 100
cols: 260

## HOW TO USE IT?

The number_of_mesos slider sets the initial number of Mesolithic people (aleatory dispersal in area with APC>=0.3).

The number_of_neos slider sets the initial number of Neolithic people (only in the Near East area with 0.3>=APC>=0.4).

SETUP initializes the mesos and neos people. The number of he turtles for each population can be set above (by default, mesos=100, neo=10).

GO starts and stops the simulation.

The neo-speed slider sets the distance, in patches, that a Neolithic can travel each year (default 0.2).

The meso-speed slider sets the distance, in patches, that a Mesolithic can travel each year (default:0.50).

The neo-birth-rate slider sets the likelihood of Neolithic reproducing each year (default:10%).

The meso-birth-rate slider sets the likelihood of Mesolithic reproducing each year (default:4.2%).

The odds-of-killing slider sets the odds that when a Neolithic encounters a Mesolithic, the Mesolithic will die (==really die or becomming neolithic).

The years monitor displays elapsed years in the model.

The population monitor shows dynamically the current number of Neolithic and Mesolithic people.

## THINGS TO NOTICE

Each turtle is born with an energy of 50
Moving costs energy

## THINGS TO TRY

Vary the odds-of-killing. How does that affect the neolithic progression?

Vary the ratio of neos-speed and meso-speed. How does that affect the neolithic diffusion?

Vary the both birth rates to see how it affects the Neolithic diffusion. Under 4%, Mesolithic is note viable.

## EXTENDING THE MODEL

Things to do:
- refine the map (intergates rivers; join the -20m asl squares)
- integrate real past climatic areas
- refine Mesolithic starting localization
- adjust birth rates to real data
...

## NETLOGO FEATURES
This model is derived from the Mammoths one:
Wilensky, U. (1997). NetLogo Mammoths model. http://ccl.northwestern.edu/netlogo/models/Mammoths. Center for Connected Learning and Computer-Based Modeling, Northwestern University, Evanston, IL.

## CREDITS AND REFERENCES

* EPSTEIN J.M. (2006) ‒Generative Social Science: Studies in Agent-Based Computational Modeling, Princeton University Press, 2006, 378 p.
* BOCQUET-APPEL J.-P. et al. (2014) ‒ Multi-agent Modelling of the Trajectory of the LBK Neolithic: A Study in Progress, in A. Whittle et P. Bickle dir, Early Farmers: The View from Archaeology and Science, Proceedings of the British Academy, British Academy, p.53‑69.
* ZANOTTI A. (2016) ‒ Modélisation de type multi-agents en archéologie : l’expansion des premiers agriculteurs Balkaniques : adaptation du modèle OBRESOC : manipulation et exploration des données simulées, phdthesis, École pratique des hautes études - EPHE PARIS Consultable à https://tel.archives-ouvertes.fr/tel-02102276

## HOW TO CITE

If you mention this model or the NetLogo software in a publication, we ask that you include the citations below.

For the model itself:
* Perrin, T. (2020). Netlogo Mediterranean Neolithization model.
CNRS, UMR5608 TRACES, Toulouse Jean-Jaurès University, Toulouse, France.

Please cite the NetLogo software as:

* Wilensky, U. (1999). NetLogo. http://ccl.northwestern.edu/netlogo/. Center for Connected Learning and Computer-Based Modeling, Northwestern University, Evanston, IL.

## COPYRIGHT AND LICENSE

Copyright 2020 Thomas Perrin.

<a rel="license" href="http://creativecommons.org/licenses/by/4.0/"><img alt="Creative Commons License" style="border-width:0" src="https://i.creativecommons.org/l/by/4.0/88x31.png" /></a><br />This work is licensed under a <a rel="license" href="http://creativecommons.org/licenses/by/4.0/">Creative Commons Attribution 4.0 International License</a>.
<!-- 2012 2020 -->