Penna bit-string model with constant population

TL;DR

This paper modifies the Penna bit-string model by removing random deaths, resulting in a fixed population driven solely by genetic factors, and shows that the core results remain consistent with previous models.

Contribution

It introduces a version of the Penna model with a constant population, eliminating random deaths and focusing on genetic causes of mortality.

Findings

Results are qualitatively similar to earlier models with random deaths.

Population remains stable without stochastic mortality factors.

Genetic diseases alone can sustain population dynamics.

Abstract

We removed from the Penna model for biological ageing any random killing Verhulst factor. Deaths are due only to genetic diseases and the population size is fixed, instead of fluctuating around some constant value. We show that these modifications give qualitatively the same results obtained in an earlier paper, where the random killings (used to avoid an exponential increase of the population) were applied only to newborns.