Modèles démographiques fondamentaux
The number of individuals or the biomass of populations, wild or domesticated, constitutes a major interest for the human economy. The dynamics of exploited wild populations must be known in order to ensure the supply of food and non-food products for a non-stop increasing world population.
In the case of wild species there are three fundamental questions to be answered: Where? When? And how much? For the domesticated species, the central question is how to produce more and more? The fifth and great question of our time is how to achieve a sustainable production? Because Homo sapiens has reached a planetary situation in which improving, or at least maintaining, the basic levels of well-being goes through the protection of the environment, the conservation of the functional and evolutionary capacities of the ecosystems and the integrity of the Holocene typical processes of the Biosphere.
Various disciplines deal, from different approaches, in resolving these fundamental questions. Among them, population ecology deals with the distribution and abundance of living beings, while population genetics is interested in studying their diversity, as well as improving and optimising varieties. Both use the tools of demography, within the framework of the theory of evolution.
This article, published as the first chapter of my PhD thesis, presents, in its first section, the three great traditions of demography: continuous-time models, discrete-time models, and branching processes models; in its second section presents, as an example of how to build life-tables and estimate demographic parameters, the analysis on the dynamics of two human populations. It will surely be of interest to anyone who wishes to learn the basics of demography, applicable to human populations and populations of other species, particularly to estimate the growth rate as well as the selective value (fitness).
How to cite this paper:
González-Dávila, G. 1994. Modèles démographiques fondamentaux. Chap. 1 of Démographie animale et biologie des populations. Modélisation et applications pour la gestion d’espèces sauvages. PhD Thesis, Montpellier II, France.