Fitness

Definition of Fitness: Capability of an individual to reproduce successfully, i.e., to transfer genes to the next generation. This is the common definition for Fitness, other definitions can be discussed in the article

Notes

1. If differences in individual genotypes affect fitness, then the frequencies of genotypes increasing fitness will increase over generations due to natural selection.
2. Darwinian fitness is the lifetime reproductive success of an organism or genotype, indexed by the average number of offspring that it produces, relative to other organisms or genotypes, and hence the relative number of copies of its genes that it passes on to future generations.
3. Absolute fitness (of a genotype) is the ratio between the number of individuals with that genotype after selection to those before selection, calculated for a single generation from absolute numbers or from frequencies.
4. Relative fitness is the fitness of individuals with a genotype relative to fitness of individuals with competing genotypes.
5. Inclusive fitness is the degree of adaptation of an organism to its environment, estimated from the number of genes belonging to its genotype that are passed on to the next generation, relative to those of other genotypes, counting both genes that it passes on directly and those that it shares with close relatives and passed on by them.