[PhD Thesis Public Presentation _ Zoom] ‐ Menglin Wang– “Worldwide historical biogeography of termites (Blattodea: Isoptera)”
Presenter: Menglin Wang
Supervisor: Prof. Thomas Bourguignon
Unit: Evolutionary Genomics Unit
Zoom URL: to be available 48 hours prior to the examination
Title: Worldwide historical biogeography of termites (Blattodea: Isoptera)
Termites are of crucial importance in terrestrial tropical and subtropical ecosystems where they play a key role in organic matter decomposition. Termites descent from a wood-feeding cockroach ancestor and diverged from the subsocial wood roach Cryptocercus more than 150 million years ago. Given that the origin of termites predates the breakup of the Pangaea, termites potentially acquired their current distribution pattern by a combination of vicariance, through continental drift, or oceanic dispersal, through over-water rafting or land bridges. The origin of termite distribution, called historical biogeography, can be studied by mean of reconstruction of ancestral distribution on time-calibrated phylogenetic trees. Although several studies have already reconstructed the global historical biogeography of termite lineages within the Neoisoptera, these studies did not investigate non-Neoisoptera termites and overlooked one biogeographic realm with unique fauna, Madagascar. In this project, I used complete mitochondrial genomes to build time-calibrated phylogenetic trees of termites and determine the precise dispersal events of yet unstudied termite lineages to and fro yet unstudied biogeographic realms. I sequenced the mitochondrial genomes of about 2500 samples including almost all termite species from North, South, and Central America and representatives of the termite diversity from Madagascar. In the chapters 1 and 2, I resolved the historical biogeography of Rhinotermitinae and the early-branching termite families Hodotermitidae, Stolotermitidae, and Archotermopsidae. In the chapter 3, I resolved the historical biogeography of termites from Madagascar. And in the chapter 4, I produced a near-complete phylogenetic tree of termites from the Americas that I used to study the diversification patterns of termites across the two continents that composed the New World. My thesis sheds light on the historical biogeography of termites at the global scale.