Comparative phylogeography and speciation processes in four boreo-montane leaf beetle species, Coleoptera, Chrysomelidae

• Main Author: Quinzin, Maud
• Other Authors: Mardulyn, Patrick, Hardy, Olivier J., Grégoire, Jean-Claude, Michaux, Johan, Gomez-Zurita, Jesus
• Format: Doctoral or Postdoctoral Thesis
• Language: French
• Published: Universite Libre de Bruxelles 2013
• Subjects: Biologie; Sciences exactes et naturelles; Phylogeography; Beetles; Chrysomelidae; Phylogéographie; Coléoptères; Chrysomélidés; spéciation; zoology; coalescence simulations/phylogéographie comparée; biologie moléculaire; biologie animale; simulations de coalescence; Coleoptera; molecular biology; Comparative phylogeography; Ice Sheet
• Online Access: http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209446; https://dipot.ulb.ac.be/dspace/bitstream/2013/209446/10/ee6df36c-7947-4852-b9d3-c77cae72fd77.txt; https://dipot.ulb.ac.be/dspace/bitstream/2013/209446/2/ff24dbd2-56eb-47a2-a9ff-5f2ee543c862.txt; https://dipot.ulb.ac.be/dspace/bitstream/2013/209446/7/9e6c695a-393c-42c6-9ad1-3a3a00c29e92.txt; https://dipot.ulb.ac.be/dspace/bitstream/2013/209446/1/c7aae023-77f1-4edc-ada3-cbb4a5d1a838.txt; https://dipot.ulb.ac.be/dspace/bitstream/2013/209446/4/d9e04910-0f3c-4ebe-ae1c-e864a106adf6.txt; https://dipot.ulb.ac.be/dspace/bitstream/2013/209446/3/c2b32a61-7b8f-4760-8af3-7f8c15bb756e.txt; https://dipot.ulb.ac.be/dspace/bitstream/2013/209446/6/c4c90908-9b61-456a-9450-c00c210345ea.txt; https://dipot.ulb.ac.be/dspace/bitstream/2013/209446/5/bd89d953-f38e-4020-bccd-ec2fdc8af07a.txt

The Quaternary climate has known dramatic global variations oscillating between long glacial and shorter interglacial periods of approximately 100 000 and 20 000 years, respectively with the last succession as an example. During the glacial episodes the continental ice sheet expansion and sea level drop, in turn, have locally disturbed the environment (at least in the northern hemisphere). These climatic and environmental disturbances caused changes in the geographic distributions of animal and plant species. For each species, the changes possibly took the form of demographic events like population extinction or fragmentation associated with genetic bottlenecks (loss in genetic diversity) and, inversely, population expansions sometimes with inherent founder effects (stochastic sampling of the source genetic diversity) and/or contact between diverged groups (secondary contact zone) resulting in genetic diversity gradients through the geographic range of the species. We therefore understand that the demographic history of a species can be reconstruct through the investigation of genetic signature(s) it possibly left and that are still observed in the genome of that species. For European taxa, phylogeographic studies taking advantage of these signatures have mainly focused their attention on temperate species; pieces of knowledge for species adapted to cold environments are too scarce although their response to climate change could not only simply follow an inverse tendency compare to temperate climate species. As a whole, this thesis project intended to study the evolutionary history of four sister species of cold-adapted leaf beetles investigating their response to past global climatic changes. The four species share many traits (life cycle, dispersal capacity, morphology, feeding behavior.) but their geographic distributions differ, further calling for interest in the factors that shaped them. Furthermore, leaf beetles are specialist insect herbivores each feeding only on one or a few different plant species. ...