Museomics of bamboo rats of genus Dactylomys (Rodentia: Echimyidae)

Abstract

Bamboo rats of the genus Dactylomys are arboreal echimids (Rodentia: Echimyidae) that inhabit the Amazon region and surroundings, commonly found close to watercourses, associated with lowland vegetation. Advanced genomic methods were the main source to test their higher-level systematics in the last decade, however, some genera such as Dactylomys are still neglected, likely due to difficulty to locate and collect them, as well as their scattered availability across national mammal collections. Mainly based on available morphological and molecular evidences, the genus is split into 3 species: D. peruanus, D. boliviensis and D. dactylinus. Morphological, geographical, and genetic variation were previously indentified among these species, however few studies have been implemented. In this context, specimens in museums and biological collections become essential material to access knowledge about their species diversity and biogeography. This proposal aims to apply recent ancient DNA museomic methods in order to sequence samples from Dactylomys (Rodentia: Echimyidae) specimens from a broad geographical and taxonomic range deposited in natural history collections. We will sequence both mitogenomes and 500 nuclear genes to infer the first phylogenomic tree for the genus and test for species delimitation and number using a wide range of methods. Next-generation sequencing-capture of nuclear exons and the recovery of the mitogenomes in silico will be conducted in a reference center of evolutionary research Institut des Sciences de l'Évolution de Montpellier (France) supervised by Dr. Pierre-Henri Fabre. The phylogenetic analyses will be conducted using distinct optimality criteria. Using Bayesian molecular dating approaches and a wide range of fossil constraints, we will date the speciation events in between Dactylomys species in order to discuss the biogeographical history and the diversification history of the bamboo rat clade in the Neotropics. (AU)