The ANR MEDSALT project aims to consolidate and expand a scientific network recently formed with the purpose to use scientific drilling to address the causes, timing, emplacement mechanisms and consequences of the largest and most recent 'salt giant' on Earth: the late Miocene (Messinian) salt deposit in the Mediterranean basin. After obtaining the endorsement of the International Ocean Discovery Program (IODP) on a Multiplatform Drilling Proposal (umbrella proposal) in early 2015, the network is planning to submit a site-specific drilling proposal to drill a transect of holes with the R/V Joides Resolution in the evaporite-bearing southern margin of the Balearic promontory in the Western Mediterranean - the aim is to submit the full proposal before the IODP dealine of April 1st 2017, following the submission of a pre-proposal on October 1st 2015. Four key issues will be addressed: 1) What are the causes, timing and emplacement mechanisms of the Mediterranean salt giant ? 2) What are the factors responsible for early salt deformation and fluid flow across and out of the halite layer ? 3) Do salt giants promote the development of a phylogenetically diverse and exceptionally active deep biosphere ? 4) What are the mechanisms underlying the spectacular vertical motions inside basins and their margins ? Our nascent scientific network will consit of a core group of 22 scientists from 10 countries (7 European + USA + Japan + Israel) of which three french scientists (G. Aloisi, J. Lofi and M. Rabineau) play a leading role as PIs of Mediterranean drilling proposals developed within our initiative. Support to this core group will be provided by a supplementary group of 21 scientists that will provide critical knowledge in key areas of our project. The ANR MEDSALT network will finance key actions that include: organising a 43 participants workshops to strengthen and consolidate the Mediterranean drilling community, supporting the participation of network scientists to seismic well site-survey cruises, organising meetings in smaller groups to work on site survey data and finance trips to the US to defend our drilling proposal in front of the IODP Environmental Protection and Safety Panel (EPSP). The MEDSALT drilling initiative will impact the understanding of issues as diverse as submarine geohazards, sub-salt hydrocarbon reservoirs and life in the deep subsurface. This is a unique opportunity for the French scientific community to play a leading role, next to our international partners, in tackling one of the most intellectually challenging open problems in the history of our planet.

The Miocene is characterized by important tectonic activity that drove sea level changes and orogeny, in turn significantly altering the climate. About 20 million years ago the contact between Afro-Arabia and Eurasia created a land-bridge that enabled faunal exchanges between these two continents. The aim of this project is to unravel the evolutionary response of the most speciose group of mammals, the rodents, in this unique context of overwhelming biotic and abiotic perturbations. Cutting-edge methodologies together with a combination of morphological and molecular approaches with time-calibrated phylogenetic trees will allow inferring the dynamics of speciation and extinction and the variation of diversity among lineages. Long-standing questions in evolutionary biology will be addressed: why certain clades are highly diversified while others are not? Is this due to the appearance of key innovations or related to extrinsic factors?