In clonal organisms the distribution of a genet is potentially unlimited in space and time. Fitness, defined as the rate of change in number of units carrying a certain allele or allele complex, can be calculated using life cycle graph analysis. The units used should be self-replicating, limited in space and time, and not unnecessarily small. The distribution of looping times (the time required for a unit to come back to the same stage) should be used rather than the mean looping time when calculating fitness. Whether vegetative and sexual reproduction are mutually exclusive or not depends on the life history of the studied population