Understanding the spatial scale and structure of marine connectivity is essential for uncovering how ocean currents shape gene flow, population structure and larval transport in reef organisms. We examined range‐wide patterns of gene flow and population structure in the tomtate ( Haemulon aurolineatum ), an abundant reef fish with a broad distribution from southern Brazil to Bermuda in the western Atlantic. We used genome‐wide...

The microbiome is central to host development and adaptation, yet the balance between vertical and environmental acquisition, and how hosts shape surrounding microbial communities, remains poorly understood. Dung beetles rely on microbial symbionts to extract nutrients from vertebrate dung, with part of their microbiome vertically inherited via a maternal faecal pellet. However, the relative importance of vertical versus horiz...

Rivers and lake systems in the southern cone of South America have been widely influenced by historical glaciations, carrying important implications for the evolution of aquatic organisms, including prompting transitions between marine and freshwater habitats and by triggering hybridization among incipient species via waterway connectivity and stream capture events. Silverside fishes ( Odontesthes ) in the region comprise a ra...

The Neotropical region represents one of the greatest biodiversity hot spots on earth. Despite its unparalleled biodiversity, regional comparative phylogeographic studies are still scarce, with most focusing on model clades (e.g. birds) and typically examining a handful of loci. Here, we apply a genome‐wide comparative phylogeographic approach to test hypotheses of codiversification of freshwater fishes in the trans‐Andean reg...

The marine‐freshwater boundary is a major biodiversity gradient and few groups have colonised both systems successfully. Fishes have transitioned between habitats repeatedly, diversifying in rivers, lakes and oceans over evolutionary time. However, their history of habitat colonisation and diversification is unclear based on available fossil and phylogenetic data. We estimate ancestral habitats and diversification and transiti...

Adaptive radiations are typically triggered when a lineage encounters a significant range of open niche space (ecological opportunity), stemming from colonisation of new areas, extinction of competitors or key innovations. The most well‐known of these is the colonisation of new areas, through either dispersal into new regions or the invasion of novel ecological regimes. One aspect of ecological opportunity that has rarely been...