An open-air site from the recent Middle Palaeolithic in the Paris Basin (France): Les Bossats at Ormesson (Seine-et-Marne)

The recent discovery (2009) and excavation of the open-air site of Ormesson (Seine-et-Marne – France) was initially intended to document a Gravettian occupation floor dated around 29,000 cal. BP and related to a preferential bison hunt. Whilst checking the thickness of the loess in which the Gravettian level was found, several other prehistoric settlements were discovered (Chatelperronian, Middle Solutrean) including two units attributed to the Middle Palaeolithic. One, level 4, seems to be particularly well-preserved. It occurs between 1 and 3 m below the main Upper Palaeolithic occupation. The lithic industry from level 4 belongs to a single kind of reduction sequence: the Discoid method. The freshness of the material and the presence of bone fragments attributed in part to horse support a general good state of preservation of this occupation. The Mousterian remains seem to cover at least 500 m2, as currently estimated. Even more exceptional is the close spatial relationship between the discoid industry, the bone pieces, remains of fireplaces and especially the numerous fragments and nodules of red colouring materials. These were brought to the site where they were utilised by the Mousterians. The used surfaces show indisputable scraping traces and facets. These recent discoveries will certainly contribute to the debate on the cognitive capacities of nearly the last representatives of the Middle Palaeolithic, and the complex stratigraphy will allow comparisons between the different periods.