Ferns as Healing Plants in Medieval Mallorca, Spain: Evidence from Human Dental Calculus

The study analyzed dental calculus from an adult male in medieval Mallorca, revealing microscopic evidence of the sporangium annulus of the fern species Asplenium trichomanes. This fern, known historically for its medicinal properties, including treatments for kidney stones and alopecia, was identified through comparison with modern samples. The presence of the sporangium annulus in dental calculus indicated the consumption of ferns, suggesting their use as medicinal plants in the Middle Ages. The authors declared no conflicts of interest.