A Mathematical Note on the Evolutionary Competitiveness of the Trisexual Nematode Auanema Rhodensis
Abstract
Trisexual species with female, male and self-fertilizing hermaphrodite sub-populations are rather exceptions in nature. Though, certain nematode/ worm species, like Auanema Rhodensis, have evolved that way. Applying Kendall-like non-logistic mating functions, we provide a series of reproduction models to holistically study the iterations between the sexes and shed light on the increased population stability/ survival strength compared to bisexual species or trisexual species with non-self-fertilizing hermaphrodites. Besides the increased survival strength, the survival of such trisexual species populations is, in contrast to usually known (bisexual) species populations, entirely linked to the relation between birth and death proportionality factors, and no population thresholds are required for survival. In that sense, while mathematically studying the complete equilibria and bifurcation landscape in terms of existence and (non-linear) stability, as well as the global dynamics of these models, we provide a comprehensive analysis of the reproduction dynamics of trisexual species.
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References
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