Seed and pollen dispersal plays a crucial role in species persistence by shaping populations on a large scale. However, empirical studies linking small-scale dispersal to large-scale patterns are scarce. We analysed the reproductive ecology of Staudtia kamerunensis (Myristicaceae), a tree species widespread in Central Africa, with the aim of linking its reproductive ecology to its large-scale population dynamics, characterised by a range expansion in the Congo Basin. We investigated gene flow and dispersal using parentage analyses and fine-scale spatial genetic structure in two landscape types, a closed-canopy forest and a forest-savanna mosaic. We found a deficit in regeneration despite fair seed production in the closed-canopy forest. Staudtia kamerunensis is a self-compatible monoecious species (8% selfed progeny), although the decay of inbreeding with age highlights inbreeding depression. Pollen dispersal (dp = 580 m) was more extensive than seed dispersal in the closed-canopy forest, where we detected a significant fine-scale spatial genetic structure (Sp = 0.0083), while gene flow was more extensive in the fragmented forest. The median diameter for reproduction was dbh50 = 58 cm whereas trees reproduce efficiently from 40 cm. This study provides insight into the reproductive ecology and dispersal of S. kamerunensis, revealing patterns that are consistent with previous studies on its population dynamics. Our results also provide insights to maintain healthy populations. We recommend a minimum cutting diameter of 60 cm or regulation to maintain at least 50% of the original reproductive potential after logging operation to preserve the reproductive potential of natural populations.

Social insects have developed a broad diversity of nesting and foraging strategies. One of these, inquilinism, occurs when one species (the inquiline) inhabits the nest built and occupied by another species (the host). Obligatory inquilines must overcome strong constraints upon colony foundation and development, due to limited availability of host colonies. To reveal how inquilinism shapes reproductive strategies in a termite host-inquiline dyad, we carried out a microsatellite marker study on Inquilinitermes inquilinus and its host Constrictotermes cavifrons. The proportion of simple, extended and mixed families was recorded in both species, as well as the presence of neotenics, parthenogenesis and multiple foundations. Most host colonies (95%) were simple families and all were monodomous. By contrast, the inquiline showed a higher proportion of extended (30%) and mixed (5%) families, and frequent neotenics (in 25% of the nests). This result from the simultaneous foundation in host nests of numerous incipient colonies which, as they grow, may compete, fight, or merge. We also documented the use of parthenogenesis by female-female pairs. In conclusion, the classical monogamous colony pattern of the host species suggests uneventful development of simple foundations dispersed in the environment, in accordance with the wide distribution of their resources. By contrast, the multiple reproductive patterns displayed by the inquiline species reveal strong constraints on foundation sites: founders first concentrate into host nests, then must attempt to outcompete or absorb the neighboring foundations to gain full control of the resources provided by the host nest.