Reynolds, R. G. | Search bioRxiv

bioRxiv2021

Chromosome-scale genome assembly of the brown anole (Anolis sagrei), a model species for evolution and ecology

Rapid technological improvements are democratizing access to high quality, chromosome-scale genome assemblies. No longer the domain of only the most highly studied model organisms, now non-traditional and emerging model species can be genome-enabled using a combination of sequencing technologies and assembly software. Consequently, old ideas built on sparse sampling across the tree of life have recently been amended in the face of genomic data drawn from a growing number of high-quality reference genomes. Arguably the most valuable are those long-studied species for which much is already known about their biology; what many term emerging model species. Here, we report a new, highly complete chromosome-scale genome assembly for the brown anole, Anolis sagrei - a lizard species widely studied across a variety of disciplines and for which a high-quality reference genome was long overdue.

genomics↗

bioRxiv2021

Molecular phylogeny of Puerto Rico Bank dwarf geckos (Squamata: Sphaerodactylidae: Sphaerodactylus)

AO_SCPLOWBSTRACTC_SCPLOWThe genus Sphaerodactylus is a very species-rich assemblage of sphaerodactylid lizards that has undergone a level of speciation in parallel to that of the well-known Anolis lizards. Nevertheless, molecular phylogenetic research on this group consists of a handful of smaller studies of regional focus (e.g., western Puerto Rico, the Lesser Antilles) or large-scale analyses based on relatively limited sequence data. Few medium-scale multi-locus studies exist-- for example, studies that encompass an entire radiation on an island group. Building upon previous work done in Puerto Rican Sphaerodactylus, we performed multi-locus sampling of Sphaerodactylus geckos from across the Puerto Rico Bank. We then used these data for phylogeny estimation with near-complete taxon sampling. We focused on sampling the widespread nominal species S. macrolepis and in so doing, we uncovered a highly divergent and morphologically distinct lineage of Sphaerodactylus macrolepis from Puerto Rico, Culebra, and Vieques islands, which we recognize as S. grandisquamis (Stejneger, 1904) on the basis of molecular and morphological characters. S. grandisquamis co-occurs with S. macrolepis only on Culebra Island but is highly genetically differentiated and morphologically distinct. Sphaerodactylus macrolepis is now restricted to the eastern Puerto Rico Bank, from Culebra east through the Virgin Islands and including the topotypic population on St. Croix. We include additional discussion of the evolutionary history and historical biogeography of the Sphaerodactylus of the Puerto Rican Bank in the context of these new discoveries.

evolutionary biology↗