Why are plants named after witches and devils in north-western Europe?

ETHNOPHARMACOLOGICAL RELEVANCE: Witches in Western Europe are associated with the use of medicinal, abortifacient, hallucinogenic, and toxic plants. Curiously, these associations are not backed up by first-hand evidence and historians are unconvinced that people convicted as witches were herbalists. Local plant names provide an untapped source for analysing witchcraft-plant relationships. AIM OF THE STUDY: We analysed vernacular plant names indicating an association with witches and devils to find out why these species and witchcraft were linked. MATERIALS AND METHODS: We constructed a database with vernacular names containing the terms witch and devil in related north-west European languages. The devil was added because of its association with witchcraft. The plant species' characteristics (e.g., medicinal use, toxicity) were assessed to determine if there were non-random associations between these traits and their names. RESULTS: We encountered 1263 unique vernacular name-taxa combinations (425 plant taxa; 97 families). Most species named after witches and/or devils were found within the Asteraceae, Ranunculaceae, and Rosaceae. For Dutch, German and English we confirmed associations between witchcraft names and toxicity. Hallucinogenic plants do not appear to be associated with witch-names. For Dutch, we found significant associations between plant names and medicinal and apotropaic uses, although we did not find any association with abortifacient qualities. CONCLUSIONS: This study demonstrates that there is a wide variety of plants associated with witches and the devil in north-western Europe. Plant names with the terms witch and devil were likely used in a pejorative manner to name toxic and weedy plants, and functioned as a warning for their harmful properties. Our study provides novel insights for research into the history of witchcraft and its associated plant species.

Expanding the Menu: Are Polyphagy and Gene Family Expansions Linked across Lepidoptera?

Evolutionary expansions and contractions of gene families are often correlated with key innovations and/or ecological characteristics. In butterflies and moths (Lepidoptera), expansions of gene families involved in detoxification of plant specialized metabolites are hypothesized to facilitate a polyphagous feeding style. However, analyses supporting this hypothesis are mostly based on a limited number of lepidopteran species. We applied a phylogenomics approach, using 37 lepidopteran genomes, to analyze if gene family evolution (gene gain and loss) is associated with the evolution of polyphagy. Specifically, we compared gene counts and evolutionary gene gain and loss rates of gene families involved in adaptations with plant feeding. We correlated gene evolution to host plant family range (phylogenetic diversity) and specialized metabolite content of plant families (functional metabolite diversity). We found a higher rate for gene loss than gene gain in Lepidoptera, a potential consequence of genomic rearrangements and deletions after (potentially small-scale) duplication events. Gene family expansions and contractions varied across lepidopteran families, and were associated to host plant use and specialization levels. Within the family Noctuidae, a higher expansion rate for gene families involved in detoxification can be related to the large number of polyphagous species. However, gene family expansions are observed in both polyphagous and monophagous lepidopteran species and thus seem to be species-specific in the taxa sampled. Nevertheless, a significant positive correlation of gene counts of the carboxyl- and choline esterase and glutathione-S-transferase detoxification gene families with the level of polyphagy was identified across Lepidoptera.

Great chemistry between us: The link between plant chemical defenses and butterfly evolution.

Plants constantly cope with insect herbivory, which is thought to be the evolutionary driver for the immense diversity of plant chemical defenses. Herbivorous insects are in turn restricted in host choice by the presence of plant chemical defense barriers. In this study, we analyzed whether butterfly host-plant patterns are determined by the presence of shared plant chemical defenses rather than by shared plant evolutionary history. Using correlation and phylogenetic statistics, we assessed the impact of host-plant chemical defense traits on shaping northwestern European butterfly assemblages at a macroevolutionary scale. Shared chemical defenses between plant families showed stronger correlation with overlap in butterfly assemblages than phylogenetic relatedness, providing evidence that chemical defenses may determine the assemblage of butterflies per plant family rather than shared evolutionary history. Although global congruence between butterflies and host-plant families was detected across the studied herbivory interactions, cophylogenetic statistics showed varying levels of congruence between butterflies and host chemical defense traits. We attribute this to the existence of multiple antiherbivore traits across plant families and the diversity of insect herbivory associations per plant family. Our results highlight the importance of plant chemical defenses in community ecology through their influence on insect assemblages.