Postdoc 3 |
Biomechanical roles of lizard osteoderms
This project is part of a HFSP Research Grant entitled "Unravelling an unusual biomineralization from nano to macro scale using advanced technologies" awarded to Dr. Merhan Moazan (University College London, U.K.), Dr. Matthews Vickaryous (University of Guelph, Canada), Dr. Arkhat Abzhanov (Imperial College London, U.K.), and Dr. Anthony Herrel (Muséum National d'Histoire Naturelle, France).
Other members of the research teams have already published very interesting papers on the osteoderms of the Gila montser (Heloderma suspectum) and the Komodo dragon (Varanus komodoensis) in Journal of Anatomy and Acta Biomaterialia I just joined the FUNEVOL team under the supervision of A. Herrel. We will study the biomechanical roles of different osteoderms during various behaviors. More details coming soon... |
Postdoc 2 |
From sounds to electric discharges: diversification of the neuromuscular functions in catfish.
Mochokid catfish use their Elastic Spring Apparatus to produce sounds. Some species from the genus Synodontis were recently shown to produce electric signals. Depending on the species, they produce sounds, electric discharges (EDs), or both (though not simultaneously) using the protractor muscle of the Elastic Spring Apparatus. Accordingly, I have formulated two hypotheses that are not mutually exclusive and are the foundations of this project. 1) Having mochokid species able to emit both EDs and sounds using the same myogenic tissue (i.e. protactor ‘muscle’) implies the development of two distinct neural pathways. 2) Electric communication (at least) in this taxon evolved as an exaptation of acoustic communication. Therefore, my research project aims to provide insights into the anatomical, physiological, and neural adaptations that underlie function changes in a vertebrate myogenic organ, and to explore the evolutionary history of acoustic and electric communication in mochokids. This study will improve our understanding of the evolution of myogenic organs and central nervous system. The latter aspect of this project has been conducted at LMU and Cornell with prof. Chagnaud and Bass
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3D reconstruction of the Elastic Spring Apparatus of Mochokus niloticus
Motoneurons (yellow-orange) and premotoneurons (green) in the proctracor nucleus
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Postdoc 1 |
Behavioral and genomic aspects of cichlid speciation
The ‘Genbas’ project (www.genbas.be) aims to characterize the genomic differentiation that drives the speciation processes in the Ophathalmotilapia cichlids at the genomic level. Five partners from four different institutions are involved: Operational Directorate Phylogeny and Taxonomy (Royal Belgian Institute for Natural Sciences), Vertebrate Section- Ichthyology (Royal Museum for Central Africa), Genomics Core (KU Leuven), Behavioral Biology Unit- Ethology and animal Psychology (ULiège), Lab of Functional and Evolutionary Morphology (ULiège). Within this network, I described the reproductive behaviors (and the associated sound production) of the different Ophthalmotilapia species. In addition, I have dissected and fixed the brain of females that have been courted by hetero- and conspecific males to study the gene expression in the different brain parts.
Watch more videos of the reproductive behavior... |
Inviting sounds of a male Ophthalmotilapia ventralis (high speed camera + hydrophone)
Mouthbrooding female (O. ventralis) with eggs Larva of O. ventralis with its yellow yolk sac
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Ph.D. thesis |
Acoustic communication in Ophidiiformes: a case study using Ophidion rochei
The biology of Ophidiiformes is poorly documented because most species are cryptic and live in the deep sea. However, their anatomy testifies they are active callers and have complex sound-producing apparatus. My PhD thesis aimed to understand the biology of acoustic communication in this taxon. This study was based on a multidisciplinary approach combining anatomy (dissection, μCT-scan), acoustics, audiometry (ABR technique), functional morphology, electromyography, histology (light and electron microscopy), and ethology. I have conducted many field works in collaboration with different laboratories and research stations (see more...) to catch living specimens of Ophidion rochei, Onuxodon fowleri, and Carapus acus .
This study has given new insights into the acoustic communication of Ophidiiformes and teleost fishes in general. Here are some examples of the most relevant results: 1) deep sexual dimorphism in the call characters and sonic mechanism supports the importance of acoustic communication for fishes living in the dark, 2) high correlation between some sound characteristics and water temperature, 3) otolith sizes are not related to hearing abilities, 4) passive acoustic can be used to determine mating periods. Moreover, thanks to our collaboration with Dr. Lugli (University of Parma, Italy), we have shown that Onuxodon fowleri is able to use its environment (i.e. its pearl oyster host) to improve its calling activities. |
3D reconstruction of the Neurocrania and anterior vertebrae (brown), otoliths (purple), and swimbladder (blue) of Ophidion rochei (left) and Carapus acus (right).
Ophidion rochei burowing into the sand & Onuxodon fowleri entering a pearl oyster
(credits: E. Parmentier)
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Master thesis |
Sound production in Dascyllus flavicaudus (Pomacentridae)
My MSc thesis gave me the opportunity to become familiar with the world of underwater acoustics, and to gain my first skills in the study of acoustic communication and behavior in fishes. It was also my first experience in the field (2 months on Moorea Island). Briefly, synchronous underwater audio–video recordings and a passive acoustic detector were used to study the acoustic behavior of the damselfish Dascyllus flavicaudus (Pomacentridae). This damselfish produces different kinds of calls depending on behaviors, which indicates that sounds in fishes are able to convey different kinds of messages. Moreover, passive acoustic recordings allowed the description of the daily and monthly cycles in sound production.
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Poster presented at the Benelux Congress of Zoology in 2009
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