Many broadly‐dispersing corals acquire their algal symbionts (Symbiodiniaceae) “horizontally” from their environment upon recruitment. Horizontal transmission could promote coral fitness across diverse environments provided that corals can associate with divergent algae across their range and that these symbionts exhibit reduced dispersal potential. Here we quantified community divergence of Cladocopium algal symbionts in two...

Population genetic markers are increasingly being used to study the diversity, ecology and evolution of Symbiodinium , a group of eukaryotic microbes that are often mutualistic with reef‐building corals. Population genetic markers can resolve individual clones, or strains, from samples of host tissue; however, samples may comprise different species that may confound interpretations of gene flow and genetic structure. Here, we...

Genetic data are rapidly advancing our understanding of various biological systems including the ecology and evolution of coral–algal symbioses. The fine‐scale interactions between individual genotypes of host and symbiont remain largely unstudied and constitute a major gap in knowledge. By applying microsatellite markers developed for both host and symbiont, we investigated the intracolony diversity, prevalence and stability...