Old taphonomy issues, new charcoal data for Mesolithic contexts: Impact of fragment size and sampling context on the assemblages of Escabasses cave (SW France)

•Archaeological charcoal taphonomy mostly relies on fragmentation studies.•Early Mesolithic charcoal data from Escabasses site (SW France) was revisited.•We tested the impact of sample type & fragment size on taxa diversity and abundance.•Sample type did not affect floristic diversity nor the proportions between taxa.•Fragment size did not impact floristic diversity but affected main taxa frequencies.•Homogeneity of charcoal samples may reflect Mesolithic behavior around fuel & fire. Does fragment size influence significantly archaeological charcoal spectra? Does the floristic content of charcoal concentrations provide a representative image of the anthracological record? These taphonomy-related questions are as old as the first methodological groundwork in anthracology and therefore, they could be considered as solved. The aim of this paper is to show that they are still topical today, as depositional and post-depositional conditions vary between archaeological contexts, periods, and sites. With this in mind, we revisited the charcoal data of an Early Mesolithic occupation, level 6 of Escabasses cave, which had the particularity of yielding a significant amount of charcoal fragments over 4 mm size and numerous combustion features. This allowed to test the impact of different size classes (mainly ]2–4[ mm vs. > 4 mm) and types of deposits (concentrated vs. scattered charcoal) on taxonomic diversity and proportions, as well as on the abundance of a key-taxon, deciduous oak (Quercus). Our results show that (i) contrarily to what is generally assumed, at Escabasses the proportions between taxa show more variability according to size class than to types of deposit; (ii) size class does not impact floristic diversity; (iii) however, the probability to find higher Quercus frequencies within the ]2–4[ mm size class is significant. These results allude to different stages in the taphonomy history of the charcoals, potentially ranging from the type of occupation and related human practices to a specific post-depositional behavior of Quercus, suggested by previous studies.