MEPS 364:129-134 (2008)  -  DOI: https://doi.org/10.3354/meps07500

ABSTRACT: Although numerous studies have explored the ecological and evolutionary consequences of relatedness on interactions among individuals, few have explored how variation in multiple paternity in natural populations affects subsequent interactions at later life history stages. Additional fathers result in a more genetically diverse brood because the ratio of half siblings to full siblings is increased. For sessile, colonial marine invertebrates, which typically have limited larval dispersal, the probability of a juvenile fusing with a neighboring conspecific is likely to be affected by the genetic composition of the brood from which it is derived. Consequently, we explored the relationship between multiple paternity and subsequent fusion-rejection interactions in the colonial ascidian Botryllus schlosseri. Microsatellites were used to calculate an effective paternity index for each brood and fusion tests among juveniles collected from recruitment plates adjacent to maternal colonies were used to assay fusion frequency. Results support the hypothesis that fusion frequency among recruits decreases with increasing levels of multiple paternity, indicating that fertilization processes affect interactions among later life stages. By extension, fertilization outcomes that affect levels of multiple paternity should be incorporated into studies of juvenile and adult interactions in other taxa with kin-structured populations.

KEY WORDS: Paternity analysis · Kin interactions · Fertilization processes · Historecognition · Ascidian · Botryllus schlosseri