The use of Odonata as model organisms for freshwater ecological research

Resumo

Freshwaters are among the most threatened ecosystem on the Earth, and countless human activities severely jeopardize their biodiversity. Invertebrates represent most of the biological diversity hosted by freshwater. These animals are essential for the correct functioning of freshwater ecosystems, and their study is needed to understand the processes and dynamics of such natural systems. Among freshwater invertebrates stand out Odonata. They represent a charismatic insect order that receives significant attention from biologists, that leaded to collecting considerable geographical, ecological, and biological information over time. Therefore, these insects can be considered good study models to test interesting evolutionary and ecological hypotheses useful for freshwater biological and ecological research. We started this work by describing the freshwater invertebrates collection of the Museum of Zoology of the University of Navarra, with particular attention to Odonata. We committed to the creation of three datasets: the first is about freshwater macroinvertebrates sampled across the entire Ebro basin; the second is a subset of the first and gathers only records of Odonata; the third is miscellaneous of data concerning odonates specimens from several projects and investigation performed at the Department of Environmental Biology of the University Navarra. We continued performing species distribution models at the European scale about Odonata to forecast the potential effect of global climate warming on the future habitat suitability of odonates and how the expected change of Odonata distribution might affect the taxonomic functional and phylogenetic diversity of their communities. Then, we investigated if the change of Odonata distribution forced by global warming is governed primarily by phylogeny or biological and ecological traits. To do that, we calculated the phylogenetic signal to verify the possible link between phylogeny and species range change, and we performed Phylogenetic Generalized Least Squares models to detect potential relationships between traits and range shifts. Finally, we explored the shortfalls and data quality characterizing the genetic reference datasets concerning European freshwater invertebrates, focusing especially on Odonata. For this purpose, we composed a comprehensive checklist of European macroinvertebrates and estimated the taxonomic and geographic shortfalls, comparing the information of our macroinvertebrate checklist with the data retrieved from GenBank and BOLD, two popular public genetic references repositories. Moreover, we verified the congruence between morphological and molecular identification performing the delimitation of Molecular Operational Taxonomic Units. We concluded our work with a general discussion and a list of considerations and suggestions concerning nature conservation and how our study could help future ecological research.