ANR Project | GAARAnti

GAARlandia land-bridge versus lesser Antilles dispersal pathways - Coupling subduction dynamics and species evolution processes in the Caribbean domain

Saturday, September 30, 2017

The purpose of the GAARAnti project is to unravel couplings between deep Earth dynamics and evolutionary processes through an innovative and original multi-disciplinary study combining Earth and Life sciences. This innovative approach will reconcile biological and geological clocks and timeframes through the combined use of radiochronological methods, biostratigraphy and phylogenetic inferences, to constrain the Cenozoic paleo-biogeography of the Antillean arc. The GAARAnti project will generate novel collaborative works between geologists/marine geophysicists and biologists/paleontologists and new results by constraining the pattern, timing, and dynamics of biodiversity in Lesser Antilles at the Cenozoic scale. This will in turn allow untangling biotic and geological constraints that forced such history. In the frame of the ongoing debate about the Cenozoic origin of terrestrial organisms of the Greater Antilles, GAARAnti will focus on the role of subduction dynamics onto the evolution of emergent areas as a promoter or an antagonist of the dispersal of the terrestrial fauna. Although it is now widely admitted that most components of Antillean terrestrial communities originated from South and Central America, the mechanisms (dispersal vs vicariance) responsible for the observed evolution and its precise timing are still highly debated. Previous studies have mainly addressed this question through Earth sciences or Life sciences separately. We hope that our innovative and original multi-disciplinary approach within the GAARAnti project will generate major advances in the knowledge of Cenozoic Antillean biodiversity dynamics.

ERC Consolidator Project | ConvergeAnt

An Integrative Approach to Understanding Convergent Evolution in Ant-eating Mammals

Wednesday, August 31, 2016

Despite its widespread occurrence across the tree of life, many questions still remain unanswered concerning the fascinating phenomenon of convergent evolution. Ant-eating mammals constitute a textbook example of morphological convergence with at least five independent origins in placentals (armadillos, anteaters, aardvarks, pangolins, and aardwolves). The large extent of convergent morphological evolution, the importance of molecular convergence, and the role of the host microbiome in diet adaptation are currently gaining acceptance. However, large-scale comparative studies combining morphology, host genomics, and metagenomics of the associated microbiome are still lacking. In the ConvergeAnt project, we propose taking advantage of the unique set of convergently evolved characters associated with the ant-eating diet to investigate the molecular mechanisms underlying phenotypical adaptation. By using state-of-the art phenotyping methods based on X-ray micro-computed tomography and Illumina sequencing technologies we will combine morphometric, genomic, and metagenomic approaches to evaluate the extent of convergent evolution in the skull of myrmecophagous placentals, in their genomes, and in their associated oral and gut microbiomes. With this ambitious research proposal, we aim at providing answers to longstanding but fundamental evolutionary questions pertaining to the mechanisms of convergent evolution. The ConvergeAnt project will be the first of its kind to apply such an integrative approach to investigate the complex interplay between the mammalian genome and its associated microbiome in a classical case of adaptive convergence driven by a highly specialized diet.

Inferring the Drivers of Neotropical Diversification Using an Integrative Macroevolutionary Approach

Tuesday, May 31, 2016

Due to its unique geological history and tropical ecology, the South American biota bears many of the known biodiversity hotspots in the world, including the richest (the Tropical Andes). The establishment of complex riverine systems, the uplift of the Andes, and Cenozoic climatic changes have all influenced Amazonian diversity. Despite an increasing number of evolutionary studies on Neotropical groups, the relative contribution of each factor is still poorly understood. The historical causes and regional determinants remain debated with new hypotheses being regularly put forward. The ensuing question ‘What gave rise to the Neotropical rainforest’s staggering biodiversity?’ is one of the most debated topics in evolutionary ecology. The debate has mostly focused on the relative contribution of abiotic versus biotic factors driving the Neotropical diversification. On the one hand, the role of historical determinants, extrinsic to species, is supposed to be key in the evolutionary history of regional groups. Changes in the physical environment like the rise of the Andes or the repeated marine transgressions have been paramount in the evolution of regional landscapes, which in turn affected the diversification and biogeography of species. On the other hand, the role of factors that are intrinsic to the species, like life-history traits or dispersal abilities are thought to be more important. For instance, a recent phylogenetic study of Amazonian birds suggested that environmental changes that occurred in South America during the Cenozoic did not significantly impact speciation. We postulate that the origin and evolution of the Neotropical biodiversity resulted from a more complex history in which both factors interacted. A statistically sound macroevolutionary perspective integrating how environments changed over time and how species traits evolved is required to identify and understand the triggers of Neotropical biodiversity. The overarching goal of the NeotroPhyl project is to conduct a series of integrative macroevolutionary analyses aiming at unraveling the biogeographic and diversification patterns that shaped Neotropical biodiversity. NeotroPhyl will build upon data and results previously obtained in the PhyloGuianas strategic project, but we will also expand our sampling taxonomically by including new biological models, and geographically by targeting groups with a Panamazonian distribution. NeotroPhyl will thus consist of analyses performed at fine taxonomic (phylogeographic) scale (genera or species complexes) to resolve species boundaries and test the role of glacial refugia throughout the Neotropics, and at higher taxonomic (phylogenetic) level (orders and families) to explore historical biogeographic patterns and identify the key drivers of diversification in the Neotropics.