There is often intense competition among species in an environment with limited resources and space, leading to the exclusion of inferior competitors, reduced species diversity, and changes in zooplankton communities. This study provides evidence that metapopulations in the real world may be complicated and changeable over time, highlighting the necessity to study such metapopulations in detail. 3 to persist at a competitive disadvantage. Thus the source–sink dynamics embedded within a well‐connected population network may allow Wiebesia sp. Moreover, the estimates of effective population sizes were comparable between the two timescales. Thus, the sinks were most likely organized into a patchy population. The clustering analysis failed to detect multiple gene pools for the whole region. There was a significant isolation‐by‐distance pattern caused mainly by migration between the competition‐free island and other islands, otherwise the pattern was negligible. Comparable levels of genetic diversity, with few private alleles and low genetic differentiation (total Fst: 0.03 pairwise Fst: 0.0005–0.0791), were revealed among all the islands. 1) consistently behaved as a net exporter of migrants, supplying large sinks. Despite a small population size, the sole island not colonized by a superior competitor wasp (Wiebesia sp. We found significant asymmetry in the pairwise migrant numbers for 22 of 28 cases on the historical timescale, but only 2 on the contemporary timescale. 3) of Ficus pumila in the Zhoushan Archipelago of China. Here, we investigated the population structure and source–sink dynamics of a pollinating wasp (Wiebesia sp. Understanding such dynamics for pollinators is particularly urgent owing to the ongoing global pollination crisis. doi:10.1371/002ĭispersal that unites spatially subdivided populations into a metapopulation with source–sink dynamics is crucial for species persistence in fragmented landscapes.
Values between solid lines and the dotted line are the parametric values allowing stable coexistence. Dotted line shows the maximum possible investment in sex. Slides for different values of b of the parametric space shown on the left panel. Hence, all the values between both surfaces allow stable coexistence. The non-linear surface defines an edge for a positive growth rate of an invader being competitively inferior or equivalent to the resident, so that all the values below that surface imply successful invasion. The linear surface is defined by the maximum possible sexual investment at equilibrium (m i * = r/b max ), so that the values below that surface do not allow permanence of the resident species. Parametric space defined by r/b max, the density-dependent sexual investment at equilibrium of the resident species (m 1 * ) and relative competitive ability of the invader (b). Invasion capability of an inferior competitor when it is not investing in sex (m 0 = 0). Invasion capability of an inferior competitor having no-sex investment. Our results suggests a previously unnoticed mechanism for species coexistence and can be extended to other facultative sexual species and species investing in diapause where similar density-dependent life-history switches could act to promote coexistence. This may happen even if the invading species is an inferior competitor.
We show that investment in sexual reproduction creates an opportunity for other species to invade and become established. We modelled the dynamics of two competing cyclical parthenogens with species-specific density-dependent sexual and diapause investment and either equal or different competitive abilities. Here we show that density-dependent sexual and diapause investment can mediate coexistence of facultative sexual species having identical niches.
Only sex-based mechanisms have been shown to create the negative feedback needed for stable coexistence of competitors with completely overlapping niches. The increasing evidence of coexistence of cryptic species with no recognized niche differentiation has called attention to mechanisms reducing competition that are not based on niche-differentiation.
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