biostudies-literatureBessho KJapan Society for the Promotion of Sciencee0295409https://www.ebi.ac.uk/biostudies/studies/S-EPMC10919683biostudies-literatureUnknown19(3)Macroalgal populations often consist of free-living haploid (gametophyte) and diploid (sporophyte) stages. Various ecological studies have been conducted to examine the demographic diversity of haploid-diploid populations with regard to the dominant stage. Here, I relaxed the assumption of classical research that the life history parameters of haploids and diploids are identical and developed a generalized haploid-diploid model that explicitly accounts for population density dependence and asexual reproduction. Analysis of this model yielded an exact solution for the abundance ratio of haploids to diploids in a population in which the ratio is determined by the balance of four demographic forces: sexual reproduction by haploids, sexual reproduction by diploids, asexual reproduction by haploids, and asexual reproduction by diploids. Furthermore, the persistence of a haploid-diploid population and its total biomass are shown to be determined by the basic reproductive number (R0), which is shown to be a function of these four demographic forces. When R0 is greater than one, the haploid-diploid population stably persists, and the ploidy ratio obtained by the analytical solution is realized.PloS oneStable demographic ratios of haploid gametophyte to diploid sporophyte abundance in macroalgal populations.PMC1091968322K0640719K16225Bessho KfalseStable demographic ratios of haploid gametophyte to diploid sporophyte abundance in macroalgal populations.Macroalgal populations often consist of free-living haploid (gametophyte) and diploid (sporophyte) stages. Various ecological studies have been conducted to examine the demographic diversity of haploid-diploid populations with regard to the dominant stage. Here, I relaxed the assumption of classical research that the life history parameters of haploids and diploids are identical and developed a generalized haploid-diploid model that explicitly accounts for population density dependence and asexual reproduction. Analysis of this model yielded an exact solution for the abundance ratio of haploids to diploids in a population in which the ratio is determined by the balance of four demographic forces: sexual reproduction by haploids, sexual reproduction by diploids, asexual reproduction by haploids, and asexual reproduction by diploids. Furthermore, the persistence of a haploid-diploid population and its total biomass are shown to be determined by the basic reproductive number (R0), which is shown to be a function of these four demographic forces. When R0 is greater than one, the haploid-diploid population stably persists, and the ploidy ratio obtained by the analytical solution is realized.2024-01-01T00:00:00Z20242026-06-12T10:09:52.9Z2025-04-04T12:35:34.914ZS-EPMC109196833845198910.1371/journal.pone.0295409