Biology

Abstract

Adaptive radiation represents one of the astonishing processes generating biodiversity, characterized by a rapid increase in number of species originating from a common ancestor, and accompanied with ecological and morphological diversification. Adaptive radiations were thoroughly studied in epigean taxa, including the renown anoles, cichlids or Darwin’s finches, whereas its contribution to subterranean biodiversity was not considered as relevant. Subterranean ecosystems were traditionally considered as extreme environments, while the inhabiting fauna was thought t represent evolutionary dead-ends. This view changed in the last decades, when it was shown that subterranean species can descend from subterranean ancestors and specialize to micro-habitats. Moreover, a recent study pointed out that adaptive radiation unfolded in subterranean freshwaters, questioning our knowledge on the origin of European fauna. Considering high species richness in some terrestrial subterranean taxa, it can be expected that freshwater amphipods do not represent an isolated case of subterranean adaptive radiation in Europe. 

With more than 900 species described, exhibiting immense morphological variability and inhabiting a wide variety of habitats throughout Southern Europe and adjacent areas, Leptodirini present one of the species richest groups in subterranean environments. Considered as terrestrial paralogue of amphipods, they represent a perfect study system to question generality of adaptive radiations in European subterranean environments. By applying comparative phylogenetic methods, we will test whether continental radiation of Leptodirini unfolded under predictable pattern of adaptive radiation and what were the potential triggers causing it. We will test whether diversification patterns met in Leptodirini repeat within different subclades, and can they be mirrored to different Southern European mountain ranges exhibiting high species richness? Finnally, we will test whethe a simple Brownian model best explains body shape diversification, or did Leptodirini evolve under a more complicated model characterized by distinct adaptive optima? To answer these questions, we will infer a large , robust molecular phylogeny (>350 species), based on phylogenomic and Sanger sequencing data. Molecular data will be accompanied with morphological and occurrence data, gathered for a wide range of Leptodirini representatives distributed throughout the clade’s range. Comparative phylogenetic methods will be used to disentangle the geographic origin of the clade, reconstruct the common ancestor and test the tempo, mode and ecological disparification in Leptodirini. A three-year project will be organized in nine working packages, comprising developmental, exploratory, analytical and dissemination packages.

An attractive and species rich group of subterranean beetles will be used to study one of the most intriguing topics in evolutionary biology. Results are expected to link micro and macro evolutionary mechanisms with the patterns of Leptodirini continental radiation. By resolving the mode and tempo of Leptodirini mega-diversification, we expect to change the view on subterranean fauna and its contribution to biodiversity in Europe. By combining phylogenomic and morphological analyses within the framework of adaptive radiation, we will introduce a novel system into ecoevolutionary research. Finally, we expect to show that subterrranean environments, despite their simplicity and remoteness, can provide exciting systems for studies of most relevant evolutionary questions.

Researchers

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The phases of the project and their realization 

The planned work is split in nine interconnected work packages, designed to facilitate fulfilling of the proposed goals. The first four packages (WP1 – 4) are designed to acquire data needed for executing the later packages, which largely include analyses of formerly acquired data (WP5 – 8). The only outlier in this sense is WP9, specifically devoted to dissemination of project results and communication with wider audience. The first package (WP1), which includes sampling of the missing genera (or species) and editing of the occurrence data will mark the onset of the project, and will be executed in the months 0-6. Along with the course of WP1, we will also start with the WP2, which will last 0-18 months, and will include generation of molecular data; designing of bait/probes, NGS and Sanger sequencing and basic bioinformatics, which will hereafter be used in phylogenetic analyses of the WP3 (month 6-24). The last WP included in the data acquiring package group, WP4, will be executed in months 0-18, and will result in morphological data, which will be used in the analyses of morphological diversification.

Once the goals of the data assembling packages are fulfilled we will transfer to hypothesis testing work packages (WP5-8). Each of the hypothesis-based packages will include exploratory phase and analytical phase, which will be wrapped up by publishing in scientific journals. The tests of adaptive radiation (WP5) will be explored and executed in months 12-30. WP6, designated to test and estimate ancestral morphologies and morphological convergence among Leptodirini will be accomplished in months 6-30, while the reconstructions of origin and test of possible triggers of radiation (WP7) will be executed in months 12-30. The last of the hypothesis testing WP’s, WP8, appointed to test how competition avoidance mechanism possibly enabled establishing of new ecological niches in subterranean environments, will be ran in months 6-18 (gathering geometric morphological data) and 24-36, when the analysis will be executed.

Wider audience and media outreach work package (WP9) will be executed throughout the whole project, with the popular articles being published once per year.

Citations for bibliographic records

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