Large-scale effects of migration and conflict in pre-agricultural groups: Insights from a dynamic model

Abstract

The debate on the causes of conflict in human societies has deep roots. In particular, the extent of conflict in hunter-gatherer groups remains unclear. Some authors suggest that large-scale violence only arose with the spreading of agriculture and the building of complex societies. To shed light on this issue, we developed a model based on operatorial techniques simulating population-resource dynamics within a two-dimensional lattice, with humans and natural resources interacting in each cell of the lattice. The model outcomes under different conditions were compared with recently available demographic data for prehistoric South America. Only under conditions that include migration among cells and conflict was the model able to consistently reproduce the empirical data at a continental scale. We argue that the interplay between resource competition, migration, and conflict drove the population dynamics of South America after the colonization phase and before the introduction of agriculture. The relation between population and resources indeed emerged as a key factor leading to migration and conflict once the carrying capacity of the environment has been reached.

Non-Hermitian Operator Modelling of Basic Cancer Cell Dynamics

“…In the past few years several macroscopic dynamical systems have been discussed using quantum tools. This approach has been considered by many authors and the range of its applications is wide, and has been successfully applied to various fields of sociology and decision making processes [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 ], biology [ 14 , 15 ], ecology [ 16 , 17 , 18 ] economics [ 19 , 20 , 21 ], population and crowd dynamics [ 22 , 23 , 24 , 25 , 26 ], etc. More applications of quantum ideas outside a standard quantum realm can be found, for instance, in the monographs [ 27 , 28 , 29 , 30 , 31 , 32 ], and in many of the references cited there.…”

Generalized Hamiltonian for a two-mode fermionic model and asymptotic equilibria

“…approaching zero in a neighborhood of the equilibrium state. This implies that the time evolution of a j (t) (j = 1, 2) can be obtained by integrating equations (17) and not by computing exp(i Ht)a j (0) exp(−i Ht).…”

“…Since 2006 [1], raising and lowering operators typical of quantum mechanics [2,3,4] have been successfully used for the mathematical modeling of several kinds of macroscopic systems. Theoretical aspects related to methods and tools in the operatorial framework, together with many applications, are discussed in [5,6]; moreover, many recent contributions in the area of quantumlike modeling outside physics, using the quantum formalism, and in particular the number representation, witness the flexibility of this general approach, which has proven effective in describing the dynamics in very different contexts, from social life and decision-making processes [7,8,9,10,11,12,13] to population migration and crowd dynamics [14,15,16,17], but even ecological processes [18,19,20,21] or political systems [22,23,24,25,26,27,28,29].…”

Modeling epidemics through ladder operators

“…This is actually the first attempt to use operatorial methods in application to infection processes: they have been successfully used in various biological contexts, to fit real data by modeling population-resources dynamics [14] , to model basic cancer cell dynamics [15] , [16] , to reproduce biological aspects of the bacterial dynamics [17] , and to model a basic epigenetic evolution [18] (see [19] , [20] for other fields of application). Our main goal is to provide a reliable long time dynamics capable to capture the final stage of the infection when the various densities of the classes have reached some sort of equilibrium values.…”