Fort Joaquim, Pérez-Losada Joaquim
Complex Systems Laboratory and Departament de Física, Universitat de Girona, Catalonia, Spain.
Hum Biol. 2012 Dec;84(6):755-72. doi: 10.3378/027.084.0601.
We use two coupled equations to analyze the space/time dynamics of two interacting languages. First, we introduce a cohabitation model, which is more appropriate for human populations than classical (noncohabitation) models. Second, using numerical simulations, we find the front speed of a new language spreading into a region in which another language was previously used. Third, for a special case, we derive an analytical formula that makes it possible to check the validity of our numerical simulations. Finally, as an example, we find that the observed front speed for the spread of the English language into Wales in the period 1961 through 1981 is consistent with the model predictions. We also find that the effects of linguistic parameters are much more important than the effects of parameters related to population dispersal and reproduction. If the initial population densities of both languages are similar, they have no effect on the front speed. We outline the potential of the new model to analyze relationships between language replacement and genetic replacement.
我们使用两个耦合方程来分析两种相互作用语言的时空动态。首先，我们引入一种共存模型，该模型比经典（非共存）模型更适用于人类群体。其次，通过数值模拟，我们找出一种新语言扩散到先前使用另一种语言的区域时的前沿速度。第三，对于一个特殊情况，我们推导出一个解析公式，该公式使得检验我们数值模拟的有效性成为可能。最后，作为一个例子，我们发现1961年至1981年期间英语扩散到威尔士的观测前沿速度与模型预测一致。我们还发现语言参数的影响比与人口扩散和繁殖相关的参数的影响重要得多。如果两种语言的初始人口密度相似，则它们对前沿速度没有影响。我们概述了新模型在分析语言替代与基因替代之间关系方面的潜力。
