Travel Tales of a Worldwide Weed: Genomic Signatures of Plantago major L. Reveal Distinct Genotypic Groups With Links to Colonial Trade Routes.

Retracing pathways of historical species introductions is fundamental to understanding the factors involved in the successful colonization and spread, centuries after a species' establishment in an introduced range. Numerous plants have been introduced to regions outside their native ranges both intentionally and accidentally by European voyagers and early colonists making transoceanic journeys; however, records are scarce to document this. We use genotyping-by-sequencing and genotype-likelihood methods on the selfing, global weed, Plantago major, collected from 50 populations worldwide to investigate how patterns of genomic diversity are distributed among populations of this global weed. Although genomic differentiation among populations is found to be low, we identify six unique genotype groups showing very little sign of admixture and low degree of outcrossing among them. We show that genotype groups are latitudinally restricted, and that more than one successful genotype colonized and spread into the introduced ranges. With the exception of New Zealand, only one genotype group is present in the Southern Hemisphere. Three of the most prevalent genotypes present in the native Eurasian range gave rise to introduced populations in the Americas, Africa, Australia, and New Zealand, which could lend support to the hypothesis that P. major was unknowlingly dispersed by early European colonists. Dispersal of multiple successful genotypes is a likely reason for success. Genomic signatures and phylogeographic methods can provide new perspectives on the drivers behind the historic introductions and the successful colonization of introduced species, contributing to our understanding of the role of genomic variation for successful establishment of introduced taxa.

From cumulative cultural transmission to evidence-based medicine: evolution of medicinal plant knowledge in Southern Italy.

In Mediterranean cultures written records of medicinal plant use have a long tradition. This written record contributed to building a consensus about what was perceived to be an efficacious pharmacopeia. Passed down through millennia, these scripts have transmitted knowledge about plant uses, with high fidelity, to scholars and laypersons alike. Herbal medicine's importance and the long-standing written record call for a better understanding of the mechanisms influencing the transmission of contemporary medicinal plant knowledge. Here we contextualize herbal medicine within evolutionary medicine and cultural evolution. Cumulative knowledge transmission is approached by estimating the causal effect of two seminal scripts about materia medica written by Dioscorides and Galen, two classical Greco-Roman physicians, on today's medicinal plant use in the Southern Italian regions of Campania, Sardinia, and Sicily. Plant-use combinations are treated as transmissible cultural traits (or "memes"), which in analogy to the biological evolution of genetic traits, are subjected to mutation and selection. Our results suggest that until today ancient scripts have exerted a strong influence on the use of herbal medicine. We conclude that the repeated empirical testing and scientific study of health care claims is guiding and shaping the selection of efficacious treatments and evidence-based herbal medicine.

Classifying diseases and remedies in ethnomedicine and ethnopharmacology.

ETHNOPHARMACOLOGICAL RELEVANCE: Ethnopharmacology focuses on the understanding of local and indigenous use of medicines and therefore an emic approach is inevitable. Often, however, standard biomedical disease classifications are used to describe and analyse local diseases and remedies. Standard classifications might be a valid tool for cross-cultural comparisons and bioprospecting purposes but are not suitable to understand the local perception of disease and use of remedies. Different standard disease classification systems exist but their suitability for cross-cultural comparisons of ethnomedical data has never been assessed. Depending on the research focus, (I) ethnomedical, (II) cross-cultural, and (III) bioprospecting, we provide suggestions for the use of specific classification systems. MATERIALS AND METHODS: We analyse three different standard biomedical classification systems (the International Classification of Diseases (ICD); the Economic Botany Data Collection Standard (EBDCS); and the International Classification of Primary Care (ICPC)), and discuss their value for categorizing diseases of ethnomedical systems and their suitability for cross-cultural research in ethnopharmacology. Moreover, based on the biomedical uses of all approved plant derived biomedical drugs, we propose a biomedical therapy-based classification system as a guide for the discovery of drugs from ethnopharmacological sources. RESULTS: Widely used standards, such as the International Classification of Diseases (ICD) by the WHO and the Economic Botany Data Collection Standard (EBDCS) are either technically challenging due to a categorisation system based on clinical examinations, which are usually not possible during field research (ICD) or lack clear biomedical criteria combining disorders and medical effects in an imprecise and confusing way (EBDCS). The International Classification of Primary Care (ICPC), also accepted by the WHO, has more in common with ethnomedical reality than the ICD or the EBDCS, as the categories are designed according to patient's perceptions and are less influenced by clinical medicine. Since diagnostic tools are not required, medical ethnobotanists and ethnopharmacologists can easily classify reported symptoms and complaints with the ICPC in one of the "chapters" based on 17 body systems, psychological and social problems. Also the biomedical uses of plant-derived drugs are classifiable into 17 broad organ- and therapy-based use-categories but can easily be divided into more specific subcategories. CONCLUSIONS: Depending on the research focus (I-III) we propose the following classification systems: I. Ethnomedicine: Ethnomedicine is culture-bound and local classifications have to be understood from an emic perspective. Consequently, the application of prefabricated, "one-size fits all" biomedical classification schemes is of limited value. II. Cross-cultural analysis: The ICPC is a suitable standard that can be applied but modified as required. III. Bioprospecting: We suggest a biomedical therapy-driven classification system with currently 17 use-categories based on biomedical uses of all approved plant derived natural product drugs.

Incense and ritual plant use in Southwest China: a case study among the Bai in Shaxi.

BACKGROUND: Ritual and religious uses of plant-derived smoke are widespread throughout the world. Our research focuses on Southwest China, where the use of incense is very common. This study aims to document and analyze contemporary ritual plant uses by the Bai people of Shaxi Township (Jianchuan County, Dali Prefecture, Yunnan Province), including their related ethnobotanical knowledge, practices, and beliefs. METHODS: The present study builds on previous ethnobotanical research in Shaxi, which started in 2005. Interviews focusing on ritual plant use and associated beliefs were carried out with a total of 44 Bai informants in September 2009 and May and June 2010. The results are supplemented with information on the local religion collected from June to December 2010. All documented species were vouchered, and are deposited at the herbaria of Kunming Institute of Botany (KUN) and the University of Zurich (Z/ZT). RESULTS: A total of 17 species have been documented for use in incense. They are always used in mixtures and are either burned in the form of powders in a censer or as joss sticks. The smell of the smoke is the main criterion for the selection of the incense plants. Incense is burned for communication with spiritual entities at graves, temples, and cooking stoves, as well as for personal well-being. Cupressus funebris Endl., Gaultheria fragrantissima Wall., and Ligustrum sempervirens (Franch.) Lingelsh. are the most important incense species. Others serve as substitutes or are used to stretch incense powders. CONCLUSIONS: In Shaxi the use of incense mixtures at the household and community level is regularly practiced for communication with ancestors, ghosts, and deities and in some cases to strengthen self-awareness. Some of the documented species are widely used in central Asia and Europe, hinting at the well documented knowledge exchange that occurred in Shaxi, which was a major hub along the influential Southern Silk Road.

Chemical analysis of incense smokes used in Shaxi, Southwest China: a novel methodological approach in ethnobotany.

AIM OF THE STUDY: Characterization and comparative analysis of the main VOCs (volatile organic compounds) present in the smoke of 11 experimentally combusted plant species used as incense in Shaxi, Southwest China. Substances which may be responsible for the pleasant smell of the smokes as well as substances with a potential pharmacological activity are discussed. MATERIALS AND METHODS: We adopt the dynamic headspace sorption method for the collection of smoke samples as a novel methodological approach in ethnobotany. The VOCs were identified using gas chromatography-mass spectrometry (GC-MS). Principal component analysis and canonical discriminant analysis were performed using PASW statistics (Version 18.0.2). RESULTS: Among the identified compounds were 10 monoterpenoids, 7 sesquiterpenoids, 6 linear hydrocarbons, 6 methoxy phenolics, 2 benzenoids, 2 polycyclic aromatic hydrocarbons, and 2 fatty acids. Based on their volatile profiles, the species are well clustered intraspecifically and separated interspecifically. The most abundant among the compounds potentially responsible for the pleasant smells of the smokes are methyl salicylate (12.28±3.90%) for Gaultheria fragrantissima leaves, δ-cadinene (15.58±2.29%) for Juniperus squamata wood, and α-Pinene for Cupressus funebris branches (9.16±7.73%) and Pistacia weinmanniifolia branches (19.52±8.66%). A couple of substances found are known for pharmacological activity, such as methylsalycilate, beta-caryophyllene and cedrol. CONCLUSIONS: The species used by the local people in Shaxi for incense differ clearly with respect to the chemical compounds of their smoke. Further, incense contains substances, which are of pharmacological interest and might support medicinal uses of smoke. Cedrol with its pleasant smell and sedative properties may be an important factor why specific plants are chosen as incense. Our findings support the idea that the effects of the use of incense as well as medicinal smoke depend on both, the cultural as well as the pharmacological context.