Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain
the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in
Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles
and JavaScript.
Chronology of the opium poppy in western Europe. The dates were calibrated with OxCal 4.4. software based on the IntCal20 atmospheric curve59,60. The asterisk corresponds to the dating performed directly on the opium poppy.