Sperm competition experiments reveal low prezygotic postmating isolation between parasitic and nonparasitic lamprey ecotypes.

The role of postmating sexual selection as a potential reproductive barrier in speciation is not well understood. Here, we studied the effects of sperm competition and cryptic female choice as putative postmating barriers in two lamprey ecotypes with a partial reproductive isolation. The European river lamprey is anadromous and parasitic of other fish species, whereas the brook lamprey is freshwater resident and nonparasitic.

A SNP marker to discriminate the european brook lamprey (Lampetra planeri), river lamprey (L. fluviatilis) and their hybrids.

Background: The European River lamprey Lampetra fluviatilis and the brook lamprey L. planeri are two closely related species that are also considered as partially reproductively isolated ecotypes. At the larval stage, they cannot be distinguished morphologically or genetically by mitochondrial DNA.

Cytidine deaminase 2 is required for antibody gene assembly in lampreys.

The antibodies of jawless vertebrates consist of leucine-rich repeat arrays encoded by somatically assembled genes. It is unknown how the incomplete germline loci are converted into functional antibody genes during B lymphocyte development in lampreys. In larvae lacking the cytidine deaminase gene, assembly fails, whereas the T lineage-associated and antigen receptor gene assemblies occur normally.

Genomic and geographic footprints of differential introgression between two divergent fish species (Solea spp.).

Investigating gene flow between closely related species and its variation across the genome is important to understand how reproductive barriers shape genome divergence before speciation is complete. An efficient way to characterize differential gene flow is to study how the genetic interactions that take place in hybrid zones selectively filter gene exchange between species, leading to heterogeneous genome divergence. In the present study, genome-wide divergence and introgression patterns were investigated between two sole species, Solea senegalensis and Solea aegyptiaca, using restriction-associated DNA sequencing (RAD-Seq) to analyze samples taken from a transect spanning the hybrid zone.

Introgressive hybridization and morphological transgression in the contact zone between two Mediterranean species.

Hybrid zones provide natural experiments where new combinations of genotypes and phenotypes are produced. Studying the reshuffling of genotypes and remodeling of phenotypes in these zones is of particular interest to document the building of reproductive isolation and the possible emergence of transgressive phenotypes that can be a source of evolutionary novelties. Here, we specifically investigate the morphological variation patterns associated with introgressive hybridization between two species of sole, and .

Using neutral, selected, and hitchhiker loci to assess connectivity of marine populations in the genomic era.

Estimating the rate of exchange of individuals among populations is a central concern to evolutionary ecology and its applications to conservation and management. For instance, the efficiency of protected areas in sustaining locally endangered populations and ecosystems depends on reserve network connectivity. The population genetics theory offers a powerful framework for estimating dispersal distances and migration rates from molecular data.