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Benjamin Geffroy
Researcher Scientist
Ifremer, Montpellier
MARBEC, MARine Biodiversity, Exploitation and Conservation
bgeffroy@ifremer.fr
Interests
I have an on-going interest in studying the physiological mechanisms that allow fishes to cope with their environments. More specifically, I'm interested on their amazing capability to reproduce, develop and thrive in different situations.
Beyond the proximate physiological mechanisms directly involved in reproduction and sex differentiation/determination, I'm also interested in ultimate causes that have promoted the existence of a plethora of sex determination types (from strictly genetic to environmental). Causes and consequences of consistent inter-individual differences in behaviour, i.e. personality, are also among my main interests.
Overall, my researches are placed in an ecological/conservation context where I try deciphering some of the various physiological and behavioural mechanisms that trigger changes at the population level.
Projects
-Reproductive Physiology-
The principal aim is to understand the mechanisms involved in Environmental Sex Determination (ESD) processes in fishes. To do so, I investigate many proximal variables, such as growth rate and behaviour that could be involved in sex determination and sex differentiation. I also use a specific set of genetic markers to detect the time window at which environmental parameters (abiotic : e.g. temperature and biotic: e.g. inter-individual relationship) affect sex determination.
-Behavioural Ecology-
I'm interested in the causes and consequences of consistent inter-individual variations in behaviour, namely Personality. As a concrete example, we find out that differences in personality might emerge from early differences in the structure of the social network, such as those animals that have lot of contacts with other from the earliest stages would develop more readily strong personality traits. We also find out that personality directly influences growth rate and might even influences sex determination in some species, such as eels.
-Human induced rapid environmental changes (HIREC)-
I first investigated the effects of different xenobiotics (anthropogenic origin), nanoparticles and uranium, at relevant concentration doses to further assess effects on population dynamics.
More recently, I've been interested on the effect of Ecotourism on fish stress, from gene to behaviour. From an ecological standpoint, I try to evaluate long-term effects of such exposure. In an evolutionary point of view, I try to understand how the information of an unpaired environment is transmitted to the offspring. The adaptive programing of offspring through maternal exposure to stressors is thus one of my current centre of interest.
These 3 axes of research are tightly linked through the investigation of coping physiology in fishes, my favourites' models.