Wagner Redundant gene functions are ubiquitous, and they are a potentially important source of evolutionary innovations on the biochemical level. It is therefore highly desirable to understand the mechanisms governing their evolution.
Gene duplication is clearly a prominent mechanism generating redundant genes.
However, because redundancy provides a protective effect against deleterious mutations, natural selection might be involved in generating and maintaining partial redundancy. Although much experimental data on redundant genes has been accumulated, no data is available that could elucidate what role selection has in their evolution. As a first step towards answering this question, a conceptually simple mathematical model for the evolution of redundancy is introduced. The population biological process at work is somewhat unusual. Rather, it acts through the low number of offspring with deleterious mutations that individuals with redundant genes will generate.