Un cas de transition démographique dans le milieu souterrain

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Summary

The cave environment is characterized by a remarkable constancy of climatic factors and by a general shortage of food resulting in low population densities. It might be expected that, in their substantially constant and rigorous environment, cave animals would tend to maintain a stable and stationary structure of the different age classes.

Demographic transition occurs when a population changes from a pyramid with a broad base indicating heavy mortality and high fecundity to a bell-shaped pyramid indicating a moderate proportion of young to old and reciprocally.