Map of Upper Palaeolithic sites of the Mediterranean basin displaying the earliest occurrence of land snails as food remains.

<p>Bold numbers indicate the calibrated chronology in ka yrs (see also <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0104898#pone-0104898-t008" target="_blank">table 8</a>). The black & white symbols denote Early Upper Palaeolithic sites with a consistent pattern of small prey exploitation including shellfish and lacking evidence of land snail consumption.