Origin of life between Scylla and Charybdis.

The "package model" discussed here is concerned with the preservation of genetic information by primordial compartments. Each viable "package" encloses a complete set of unlinked genes in varying numbers of copies. Due to stochastic distribution and error-prone replication two potent perils endanger the informational integrity of packages: fluctuation and mutation. A computer simulation was used to quantify the effects of fluctuation, mutation, and package death by accident. Assuming reasonable rates for these parameters it is suggested that life started out with compartments containing not more than 3 different genes.