Figure 1.
Fluctuations in male fitness components resulting from coevolution between a mitochondrial and nuclear locus. The figure illustrates the case of sequential substitutions of male-harming mtDNA alleles, each followed by the substitution of a compensatory allele in the nuclear genome that restores male fitness. The mean time between substitutions at a mitochondrial locus is TM. The mean lag between a mitochondrial substitution and a nuclear compensatory substitution is TC. The time that males spend within the low-fitness state depends on the tempo of mitochondrial substitutions relative to the lag time of compensatory substitutions. (Online version in colour.)