Abstract
AbstractAimAlthough thermophilous and arid‐dwelling relict biotas constitute a singular component of European biodiversity of high conservation value, we still largely ignore their biogeographic history. In this study, we investigate the geographical diversification of the Maghrebian‐Levantine crested grasshopper and its colonization of semiarid habitats of southeastern Iberia to gain insights into the historical processes underlying the biogeographic connections between northern African and southern European arid‐dwelling faunas.LocationMediterranean region.TaxonCrested grasshoppers Dericorys millierei and Dericorys carthagonovae (Orthoptera: Dericorythidae).MethodsWe used genomic data (ddRAD‐seq) to quantify the genetic structure of populations, infer the phylogenetic relationships among them, estimate divergence times, and elucidate the demographic processes accompanying the colonization of southeastern Iberia. Genomic‐based inferences were interpreted in the light of eustatic sea‐level reconstructions and species’ range dynamics derived from palaeodistribution modelling at fine temporal resolution.ResultsClustering analyses showed a strong genetic structure and phylogenomic inference revealed that Iberian populations are nested within a Maghrebian clade. Molecular dating analyses indicated that all lineages diverged during the Pleistocene (<1.6 Ma), with point estimates coinciding with glacial periods and the accompanying sea level drops. According to palaeodistribution modelling, the species experienced severe range contractions during the coldest stages of the Pleistocene.Main conclusionsOur results indicate that the colonization of the Iberian Peninsula likely took place during the marked sea level drops characterizing the high‐amplitude climatic oscillations of the late Quaternary (<0.5 Ma), which considerably reduced overseas distances between northern African and southern European landmasses and might have eased transmarine exchanges of terrestrial faunas. These findings emphasize the high relevance of the Maghreb region as a source of European thermophilous biotas and corroborate post‐Messinian biogeographic connections between the two continents despite the barrier effect of the Mediterranean Sea.
Highlights
Distributed thermophilous, arid-adapted, and steppe- dwelling biotas constitute a singular component of European biodiversity, often including relict species that are the only living representatives in the continent at different taxonomic ranks (Husemann et al, 2014; Kajtoch et al, 2016; Ribera & Blasco- Zumeta, 1998)
Divergence time estimates indicate that all trans-M editerranean populations of D. millierei diverged during the Quaternary (
This study illustrates the potential of integrating genomic data, eustatic sea-level reconstructions, and palaeodistribution modelling at fine temporal resolution to shed light on the processes underlying the distribution of thermophilous and arid-dwelling faunas shared between southern Europe and arid and desertic regions from North Africa
Summary
Arid-adapted, and steppe- dwelling biotas constitute a singular component of European biodiversity, often including relict species that are the only living representatives in the continent at different taxonomic ranks (Husemann et al, 2014; Kajtoch et al, 2016; Ribera & Blasco- Zumeta, 1998) In some instances, these taxa show remarkable genetic distinctiveness (i.e., vicariant lineages, subspecies or even species) with respect to core distributions in Central Asia or North Africa, representing a unique evolutionary legacy of high conservation value (Husemann et al, 2014; Kajtoch et al, 2016; Kirschner et al, 2020). The role of human-mediated dispersal or historical introductions in the distribution of some thermophilous organisms in southern Europe cannot be discarded (Husemann et al, 2014)
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
