Fig. 2

Pairwise invasibility plots for the maternally controlled asymmetric inheritance of mitochondria. Values of paternal leakage (π) for which invasion is successful are within the regions marked with “+”. Arrows show the direction of trait evolution assuming small mutational changes in π. a For weak epistatic interactions (lower ξ) and low mutation rates (μ), there are two evolutionarily stable states (filled circles), one at which mitochondria are symmetrically inherited from both gametes (π = 1), and the second at which there is full uniparental inheritance of mitochondria (π = 0). These are separated by a singular point between π = 0 and π = 1 which is an evolutionary repeller (open circle). b With higher mutation rates (μ), the zone of attraction to the asymmetric equilibrium (π = 0) increases, until the symmetric equilibrium is eliminated. c, d Increasing the degree of epistasis (higher ξ) increases the short-term benefit of mixing mitochondria and weakens the attraction of the asymmetric equilibrium (π = 0). The number of mitochondria was set to M = 50