Vincent Mouchi

Vincent Mouchi Study of the connectivity of the Mytilidae communities associated with deep-sea hydrothermal environments of the medio-Atlantic ridge. Ou Study of the larval dispersal of the natural population in hydrothermal environments.

Hydrothermal environments are areas located in the deep sea, along ridge and particularly in the mid-Atlantic ones. They are isolated from one another by several hundred and sometimes thousands of kilometers. These environments are characterized by the presence of many organisms whose survival depends on their environment. These environments are also very ephemeral; they can disappear and reappear in elsewhere depending on tectonic activity.

The survival of these organisms (molluscs) is made possible by larval dispersal. After reproduction, larvae will escape into the ocean to colonize other sites and take part in the evolution of a new site or a preexisting one. Vincent tries to find the origin of the larvae from juveniles or adults using the chemical composition of their shells. This tells us how many kilometers the larvae have travelled during dispersal.

Why this subject ?

Vincent had already started working on the subject in a prior postdoc, but in the Pacific Ocean. In the Atlantic, the impact of deep-sea mining on the biodiversity of hydrothermal environments has been studied for several years.

Deep-sea mining has been one of the major political and economic issues of the last few years, and these environments are very rich in heavy metals, which are much in demand by industry. Plans have been made or mining programs drawn up to exploit these environments, but we don't know what impact it could have on seabed. By determining the origin of the larvae, we could determine which sites are important to preserve in order to maintain the population on a large scale.

A funny story related to this subject ?

To analyze the composition of the shells with great precision, Vincent used a particle accelerator (synchrotron). He received a recommendation to use a nail polish from a well-known brand to attach the small samples without contaminating them. Once he passed the command, he forgot it entirely, and when the receptionist received the package, he couldn't remember what it might be. So Vincent opened it in front of the receptionist, and after remembering its purpose, he swore that it was for purely scientific use. As for the receptionist, she remained very doubtful...