Sexual reproduction may evolve as a trait that enhances the competitive quality of the reproducing unit
It is indeed intriguing that the theoretically deduced interference competition in multicellular animals is exactly so high that the predicted evolutionary equilibrium to the degree of sexual reproduction matches the well-known form of sexual reproduction where a female and a male provide equal fractions of the genome in the offspring.
It is also intriguing that selection by density dependent competitive interactions predicts the absence of sexual reproduction in single-celled organisms. And that it, on the continuum to higher levels of sexual reproduction, with several males per female, continues to predict the form of sexual reproduction that is known from Earth (see section on offspring workers for theoretical explanation).
While these predictions provide no direct evidence that prove that sexual reproduction has evolved by selection by density dependent competitive interactions, the selection outbalances both the cost of the male and the cost meiosis as they occur in mobile organisms. This form of sexual reproduction contrasts to sessile organisms, where sex most often occurs among hermaphrodites that avoid both the cost of the male and the cost of meiosis. This transition is also expected from Malthusian Relativity, because it is not possible to use neither male individuals and nor sexual reproduction to enhance the interactive quality of a sessile reproducing unit.