Consistent patterns of common species across tropical tree communities.

Trees structure the Earth's most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations1-6 in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth's 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories7, we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world's most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees.

Ethnobotany and phytochemistry of plants used to treat musculoskeletal disorders among Skaw Karen, Thailand.

CONTEXT: Musculoskeletal system disorders (MSD) are prevalent around the world affecting the health of people, especially farmers who work hard in the field. Karen farmers use many medicinal plants to treat MSD. OBJECTIVE: This study collects traditional plant-based remedies used by the Skaw Karen to treat MSD and evaluates their active phytochemical compounds. MATERIALS AND METHODS: The ethnobotanical study was conducted in six Karen villages in Chiang Mai province using semi-structured interviews were of 120 informants. The data were analyzed using ethnobotanical indices including use values (UV), choice value (CV), and informant consensus factor (ICF). Consequently, the 20 most important species, according to the indices, were selected for phytochemical analysis using LC-MS/MS. RESULTS: A total of 3731 use reports were obtained for 139 species used in MSD treatment. The most common ailments treated with those plants were muscular pain. A total of 172 high-potential active compounds for MSD treatment were identified. Most of them were flavonoids, terpenoids, alkaloids, and steroids. The prevalent phytochemical compounds related to treat MSD were 9-hydroxycalabaxanthone, dihydrovaltrate, morroniside, isoacteoside, lithocholic acid, pomiferin, cucurbitacin E, leonuriside A, liriodendrin, and physalin E. Sambucus javanica Reinw. ex Blume (Adoxaceae), Betula alnoides Buch.-Ham. ex D.Don (Betulaceae), Blumea balsamifera (L.) DC. (Asteraceae), Plantago major L. (Plantaginaceae) and Flacourtia jangomas (Lour.) Raeusch. (Salicaceae) all had high ethnobotanical index values and many active compounds. DISCUSSION AND CONCLUSIONS: This study provides valuable information, demonstrating low-cost medicine plants that are locally available. It is a choice of treatment for people living in remote areas.

Biogeography and environmental preferences of Butia yatay (Mart.) Becc.

During the Quaternary, Chaco Phytogeographic Domain (Chaco) flora in subtropical South America experienced temperature and humidity fluctuations, primarily driven by wind dynamics, leading to significant shifts in species distribution. The palm Butia yatay is endemic to the Chaco and thrives in areas characterized by a warm-rainy climate and mostly restricted to sandy soils. To investigate the current geographic distribution of suitable habitat for B. yatay while assessing the significance of soil variables, we employed two distinct algorithms in species distribution modeling (SDM). We also determined whether the distribution of B. yatay has changed since the Pleistocene and whether these changes align with previously proposed Pleistocene refugia. In the present SDMs, we considered two separate sets of predictors, one set with bioclimatic variables only and the other set with bioclimatic topographic and soil variables. Additionally, we reconstructed the historical geographic distribution of suitable habitats using bioclimatic data. Our results suggested that the primary determinants of B. yatay's current distribution include precipitation and temperature of the driest month and soil cation exchange capacity. Incorporating soil variables affected the estimated size and range of suitable areas. Projections into the past indicated similar suitable habitat distributions during interglacial periods compared with the present. During the Last Glacial Maximum, climatically suitable habitat may have shifted northward, partially overlapping with previously suggested Pleistocene refugia located between the Paraná and Uruguay Rivers. These findings indicate the main factors driving the distribution and ecology of B. yatay and enhance understanding of subtropical flora shifts during the Quaternary. The approach also may prove valuable for other studies within the Chaco.

Ontogeny of the pollinium in Hoya carnosa provides new insights into microsporogenesis.

The presence of a pollinium is a distinct character in Apocynaceae which is important for phylogenetic analysis. The pollinium of Hoya has an outer sporopollenin wall and a pellucid margin which are adaptive features. However, their ontogeny and related evolutionary implications are not entirely understood. Therefore, a representative species Hoya carnosa was selected to investigate the pollinium development using light and electron microscopy and cytochemical tests. In contrast to the microsporogenesis in most angiosperms, which is associated with callose, the non-callosic intersporal walls in Hoya carnosa, together with the successive cytokinesis and linear form of the tetrad, represent an alternative pattern of microsporogenesis. This pattern has specific implication for the early stages of pollen morphogenesis. The absence of exine and apertures in the pollen grains in the pollinium could result from a combination of factors including the absence of callose in the early stages and the modifications in later developmental pathways, e.g., the sporopollenin accumulation pathway. The pollinium wall is an exine without stratification, its surface lacks sculptures, and it provides structural support and protection. The pollen tubes germinate through the pellucid margin and germinating ridge which are specialized features. The pellucid margin originates from aborted microspores. The germinating ridge that lies on the outer side of the pellucid margin develops in the same way as a classic pollen exine. The pollen grains are aggregated by intine fusion which is favorable for tube germination and growth. Comparing Asclepiadoideae with the other two subfamilies of Apocynaceae that develop a pollinium, the pollinium of Asclepiadoideae has reduced deposition of sporopollenin in the inner walls but an increase in the outer pollinium wall, thus making the inner walls more reduced and simplified, and the outer walls more solid. The adaptive characters of the pollen wall structure and the cohesion mechanism suggest that the pollinium of Hoya carnosa is a derived form of pollen aggregation.

Medicinal plants used by rural Thai people to treat non-communicable diseases and related symptoms.

Non-communicable diseases (NCDs) are becoming more common in remote regions, whereas previously they were more common in middle-class to wealthy societies. The rising prevalence and severity of NCDs has increased the demand for medical innovation in this space. In this regard, knowledge of traditional medicines used in the treatment of NCDs, by people in the remote communities of Thailand, represents an innovation opportunity. This study aims to use data on ethnomedicinal plants used by local Thai people to identify plant candidates for study of safety and efficacy against a range of specified NCDs. Data were taken from both the literature and interviews from 230 locations in Thailand. The consulted literature was published in the years from 1990 to 2020. Ethnomedicinal field observations were made in person, in villages in Nan and Chiang Rai provinces, in 2021. Data includes names of plants used to target NCDs, and names of target diseases. Important plant species were identified based on the number of use reports and use values together with results from Bayesian approach. A total of 766 plant species were recorded in the treatment of NCDs. Most of the species that were described by informants were used to target diabetes, hypertension, chronic respiratory and renal diseases. This study proposes several plant species that have potential as treatments against NCDs. Many of these important species have insufficient scientific data to support their uses. The study suggests that assessment of efficacy and safety should be the next logical steps.

Three Amazonian palms as underestimated and little-known sources of nutrients, bioactive compounds and edible insects.

Mauritia flexuosa, Bactris gasipaes, and Oenocarpus bataua are among the main palms in the Amazon used for food and medicinal purposes. The food most commonly derived from these are fruits, oil, and the larvae of the insect Rhynchophorus palmarum reared in their trunks. Palm fruits are used for oil extraction as they are rich in saturated fatty acids, fiber, pro-vitamin A, carotenoids, tocopherols, macro and microelements, and polyphenols. Furthermore, the larvae of R. palmarum are rich in lipids, vitamin E, and proteins. This review analyzes the chemical composition of the fruit and oil of these palm species, as well as the R. palmarum larvae that breed in them. Our aim is to present information that is not widely known in order to demonstrate the potential of these palms as sources of plant-based and animal food with high nutritional and functional values.

Phylogenomic relationships and historical biogeography in the South American vegetable ivory palms (Phytelepheae).

The palm tribe Phytelepheae form a clade of three genera and eight species whose phylogenetic relationships and historical biogeography are not fully understood. Based on morphological similarities and phylogenetic relatedness, it has been suggested that Phytelephas seemannii and Phytelephas schottii are synonyms of Phytelephas macrocarpa, implying the existence of only six species within the Phytelepheae. In addition, uncertainty in their phylogenetic relationships in turn results in blurred biogeographic history. We inferred the phylogenomic relationships in the Phytelepheae by target-capturing 176 nuclear genes and estimated divergence times by using four fossils for time calibration. We lastly explored the biogeographic history of the tribe by inferring its ancestral range evolution. Our phylogenomic trees showed that P. seemannii and P. schottii are not closely related with P. macrocarpa, and therefore, support the existence of eight species in the Phytelepheae. The ancestor of the tribe was widely-distributed in the Chocó, Magdalena, and Amazonia during the Miocene at 19.25 Ma. Early diversification in Phytelephas at 5.27 Ma could have occurred by trans-Andean vicariance after the western Andes uplifted rapidly at âˆ¼ 10 Ma. Our results show the utility of phylogenomic approaches to shed light on species relationships and their biogeographic history.

Medicinal Plants Used for Treating Mild Covid-19 Symptoms Among Thai Karen and Hmong.

Background: The COVID-19 pandemic is causing many severe problems globally, and it is not known for how long it will last. The only hope we have for dealing with the problem is to produce sufficient vaccines and administer them efficiently. However, the current demand for vaccines greatly exceeds the supply, and many people will suffer from the disease for still some time. Moreover, the period for immunity obtained by the vaccines remains unknown, and we cannot predict how long the world will suffer the COVID-19 infections. Therefore, there will be a continued demand for treatments of its symptoms. An alternative solution for providing such treatment is the use of traditional medicinal plants. Aims: To document medicinal plants used by Hmong and Karen in Thailand to treat mild symptoms of COVID-19. Methods: Traditional knowledge about ethnomedicinal plants used by Hmong and Karen in Thailand for treating mild symptoms listed by WHO as associated with COVID 19, was collected in field interviews and extracted from the literature. Results: We identified 491 plant species used medicinally by both ethnic groups to treat fever, cough, diarrhea, muscle pain and ache, rash, headache, sore throat, and conjunctivitis. Of the 491 species 60 were mentioned at least five times in the literature or in our field data. Of these 60 species, we propose the most commonly used ones for treatments of mild COVID-19 symptoms. Ten of these most commonly mentioned species were used for treatments of fever, nine for treatment of cough, four for treatment of diarrhea, two for treatment of rash, and a single species was used to treat muscle pain and headache. Conclusion: This study suggests alternative treatments for mild symptoms of COVID-19 with medicinal plants that are traditionally used by the ethnic minority groups of the Hmong and Karen in Thailand. Although COVID-19 is a new disease, its mild symptoms are shared with many other diseases. Traditional knowledge on medicinal plants used by the Thai Karen and Hmong could help in the treatments of these symptoms associated with COVID-19. Many of the proposed plants were used abundantly by both ethnic groups, and other studies on biological activities support their efficacy in such treatments.

Cannabinoids from inflorescences fractions of Trema orientalis (L.) Blume (Cannabaceae) against human pathogenic bacteria.

BACKGROUND: Cannabinoids; tetrahydrocannabinol (THC), cannabidiol (CBD) and cannabinol (CBN), might show antibacterial activity. Trema orientalis is a species in the Cannabaceae that is closely related to Cannabis through plastome phylogenetic evidence. This species is widely distributed throughout tropical Asia and is used as traditional medicine, particularly for the treatment of infectious diseases. However, no studies on the antibacterial activity of cannabinoid-containing inflorescences extracts are available. Thus, the aim of this study was to determine cannabinoid content and antibacterial activity of inflorescences fractions from T. orientalis native to Thailand. METHODS: We hypothesized that inflorescences from T. orientalis might display cannabinoids similar to Cannabis because of their close taxonomic relationship. We extracted the mature inflorescences and infructescence of T. orientalis in three disparate populations from different Thailand floristic regions. Extractions were subsequently partitioned into hydrophilic and lipophilic fractions using distilled water and chloroform. The lipophilic extracts were further fractionated by the column chromatography with gradient elution and analyzed by gas chromatography-mass spectrometry (GC-MS). Characterized cannabinoids were used in bioassays with multidrug-resistance bacteria. RESULTS: Lipophilic extracts and fractions of inflorescences from all Thailand floristic regions consistently displayed cannabinoids (THC, CBD and CBN) in various quantities. These extracts exhibited inhibitory activity for Staphylococcus aureus, Pseudomonas aeruginosa, and Acinetobacter baumannii strains with minimum inhibitory concentration values varying from 31.25 to 125 µg/mL. CONCLUSION: Our study is the first to report cannabinoid detection in extracts from inflorescences of T. orientalis, a species in the Cannabaceae. These extracts and their fractions containing cannabinoids showed pronounced antibacterial activity. The use of analytic methods also demonstrated reproducible cannabinoid extraction.

Dolichos kongkandae sp. nov. and lectotypification of D. fragrans (Leguminosae, Papilionoideae) from Asia.

Dolichos kongkandae is described as a new species from Asia and includes a line drawing, photographs and information on its distribution and ecology. The morphological differences between D. kongkandae and the morphologically similar D. tenuicaulis are highlighted and clarified. Additionally, a lectotype for D. fragrans is designated.

Edaphic heterogeneity and the evolutionary trajectory of Amazonian plant communities.

We investigated how the phylogenetic structure of Amazonian plant communities varies along an edaphic gradient within the non-inundated forests. Forty localities were sampled on three terrain types representing two kinds of soil: clayey soils of a high base cation concentration derived from the Solimões formation, and loamy soils with lower base cation concentration derived from the Içá formation and alluvial terraces. Phylogenetic community metrics were calculated for each locality for ferns and palms both with ferns as one group and for each of three fern clades with a crown group age comparable to that of palms. Palm and fern communities showed significant and contrasting phylogenetic signals along the soil gradient. Fern species richness increased but standard effect size of mean pairwise distance (SES.MPD) and variation of pairwise distances (VPD) decreased with increasing soil base cation concentration. In contrast, palm communities were more species rich on less cation-rich soils and their SES.MPD increased with soil base cation concentration. Species turnover between the communities reflected the soil gradient slightly better when based on species occurrences than when phylogenetic distances between the species were considered. Each of the three fern subclades behaved differently from each other and from the entire fern clade. The fern clade whose phylogenetic patterns were most similar to those of palms also resembled palms in being most species-rich on cation-poor soils. The phylogenetic structuring of local plant communities varies along a soil base cation concentration gradient within non-inundated Amazonian rain forests. Lineages can show either similar or different phylogenetic community structure patterns and evolutionary trajectories, and we suggest this to be linked to their environmental adaptations. Consequently, geological heterogeneity can be expected to translate into a potentially highly diverse set of evolutionarily distinct community assembly pathways in Amazonia and elsewhere.

Nutrient and Mineral Compositions of Wild Leafy Vegetables of the Karen and Lawa Communities in Thailand.

Wild food plants are commonly used in the traditional diets of indigenous people in many parts of the world, including northern Thailand. The potential contribution of wild food plants to the nutrition of the Karen and Lawa communities remains poorly understood. Wild food plants, with a focus on leafy vegetables, were ranked by the Cultural Food Significance Index (CFSI) based on semi-structured interviews. Twelve wild plant species were highly mentioned and widely consumed. The importance of the wild vegetables was mainly related to taste, availability, and multifunctionality of the species. Their contents of proximate and minerals (P, K, Na, Ca, Mg, Fe, Mn, Zn, and Cu) were analyzed using standard methods. The proximate contents were comparable to most domesticated vegetables. The contents of Mg (104 mg/100 g FW), Fe (11 mg/100 g FW), and Zn (19 mg/100 g FW) in the wild leafy vegetables were high enough to cover the daily recommended dietary allowances of adults (19-50 years), whereas a few species showed Mn contents higher than the tolerable upper intake level (>11 mg/100 g edible part). The wild leafy vegetables, therefore, are good sources of minerals and we recommend their continued usage by indigenous people. Further research on these wild leafy vegetables' contents of antioxidants, vitamins, heavy metals, anti-nutrient factors, and food safety is recommended.

Ethnomedicinal Knowledge of Traditional Healers in Roi Et, Thailand.

Traditional healers in Thailand are a primary source of health care for the Thai people. Highly experienced traditional healers are generally older people and they continue to pass away without recording or passing on their knowledge. Consequently, the cumulative knowledge held by traditional healers regarding the use of medicinal plants is being eroded and could be lost. In this study, we aimed to identify and document the medicinal plants and associated ethnobotanical knowledge held by traditional healers in Roi Et in northeastern Thailand. Data and plant specimens were collected from four traditional healers of the Phu Tai people. They were selected by purposive sampling and questioned using a semi-structured interview. The interviews covered their training, the ailments treated, treatment techniques, method of preparation and in addition, several healing sessions were observed. During field walks, we searched for the medicinal plants with the healers to review and document the availability of medicinal plants at each locality and in different habitats around the villages. Use values (UV) were calculated to estimate the importance of each medicinal plant and informant agreement ratios (IAR) were calculated to understand how widely known the uses were. The four Phu Tai traditional healers knew 162 medicinal plant species in 141 genera and 63 families. The family with the most medicinal plants was Leguminosae with 15 species. The plant part that they used most commonly was the stem, which was used for 82 species (49%). The most common preparation method was decoction, which was done for 124 species (75%). The most important and widely used medicinal plants were Rothmannia wittii, which had the highest use value (UV = 1.7). Most medicinal plants were used for treating tonic (34 species (21%)). Jaundice had the highest informant agreement ratio (IAR = 0.5). The most common life form among the medicinal plants was trees (56 species (34%)). The medicinal plants were mostly collected in community forests (81 species (49%)). Considering the richness of the healer's pharmacopeia, and the fact that their profession is not being perpetuated, this study points to the urgent need to document the traditional knowledge from the old herbalists before it disappears with the last practitioners from rural communities in Thailand.

Using ICPC-2 Standard to Identify Thai Zingiberaceae of Pharmacological Interest.

The Economic Botany Data Collection Standard (EBDCS) is a widely used standard among ethnobotanists. However, this standard classifies ethnomedicinal uses into categories based on local peoples' perception. It is difficult to apply in pharmacological research. The International Classification of Primary Care (ICPC), now updated to ICPC-2, is more related to medical terms, but is rarely used among ethnobotanists. This study aims to apply the ICPC-2 to classify metadata of the ethnomedicinal uses of Zingiberaceae plants in Thailand, in order to identify important medicinal taxa for future research. Data on the ethnomedicinal uses of Thai gingers were collected from 62 theses, journal articles, scientific reports and a book, published between 1990 and 2019. Scientific plant names were updated using The World Checklist of Vascular Plants (WCVP) website. Informant Consensus Factor (ICF) was used to identify the medicinal issues commonly treated with gingers, and the Cultural Importance Index (CI) was used to identify species that might have pharmacological potential. We found records of 76 ginger species with ethnomedicinal uses, and together they had 771 use reports. The gingers were commonly used for treatments related to digestive system conditions, particularly abdominal pain and flatulence. Gingers remain exceedingly important in Thai ethnomedicine, with a high number of useful species. They are used to treat a variety of health conditions, but most commonly such ones that are related to the digestive system. Apart from the popular studied ginger, Curcuma longa, we identified a number of other useful gingers in Thailand.

Ethnomedicinal Plant Knowledge of the Karen in Thailand.

The Thai Karen, the largest hill-tribe in Thailand, guard substantial ethnomedicinal plant knowledge, as documented in several studies that targeted single villages. Here, we have compiled information from all the reliable and published sources to present a comprehensive overview of the Karen ethnomedicinal plant knowledge. Our dataset covers 31 Karen villages distributed over eight provinces in Thailand. We used the Cultural Importance Index (CI) to determine which species were the most valuable to the Karen and the Informant Consensus Factor (ICF) to evaluate how well distributed the knowledge of ethnomedicinal plants was in various medicinal use categories. In the 31 Karen villages, we found 3188 reports of ethnomedicinal plant uses of 732 species in 150 plant families. Chromolaena odorata, Biancaea sappan, and Tinospora crispa were the most important medicinal plants, with the highest CI values. The Leguminosae, Asteraceae, Zingiberaceae, Euphorbiaceae, Lamiaceae, Acanthaceae, Apocynaceae, and Menispermaceae were the families with the highest CI values in the mentioned order. A high proportion of all the 3188 Karen use reports were used to treat digestive, general and unspecified, musculoskeletal, and skin disorders.

Medicinal Plants for Treating Musculoskeletal Disorders among Karen in Thailand.

Millions of people suffer from Musculoskeletal System Disorders (MSDs), including Karen people who work hard in the fields for their subsistence and have done so for generations. This has forced the Karen to use many medicinal plants to treat MSDs. We gathered data from 15 original references covering 27 Karen communities and we document 461 reports of the use of 175 species for treating MSDs among the Karen people in Thailand. The data were analyzed by calculating use values (UV), relative frequency of citation (RFC) and informant consensus factor (ICF). Many use reports and species were from Leguminosae and Zingiberaceae. Roots and leaves were the most used parts, while the preferred preparation methods were decoction and burning. Oral ingestion was the most common form of administration. The most common ailment was muscle pain. Sambucus javanica and Plantago major were the most important species because they had the highest and second-highest values for both UV and RFC, respectively. This study revealed that the Karen people in Thailand use various medicinal plants to treat MSDs. These are the main resources for the further development of inexpensive treatments of MSDs that would benefit not only the Karen, but all people who suffer from MSD.

Anti-Infectious Plants of The Thai Karen: A Meta-Analysis.

Pharmacology has developed many drugs to treat infections, but many people, especially in developing countries, cannot afford to purchase them, and still depend on traditional knowledge and local medicinal plants to fight off infections. In addition, numerous microbes have developed resistance to the pharmaceutical drugs developed to fight them, and for many, such as Covid-19, effective drugs remain to be found. Ethnomedicinal knowledge is useful, not only for local people as a source of medicine for primary health care, but also for new pharmacological discoveries. This study aimed to identify the plants that the Karen, the largest hill-tribe ethnic minority in northern and western Thailand, use for treatments of infectious diseases. We present a meta-analysis of data from 16 ethnobotanical studies of 25 Karen villages with the aim of understanding traditional knowledge and treatments and point to potential plants for further pharmacological development. The Karen used 127 plant species from 59 plant families to treat infections and infectious diseases. The Cultural Important Index (CI) showed that the Leguminosae, Euphorbiaceae, Asteraceae, Lauraceae, Apocynaceae, Menispermaceae, and Lamiaceae were the most commonly used families. As for species, Cleidion javanicum, Tinospora crispa, Litsea cubeba, Aesculus assamica, Tadehagi triquetrum, Senna alata, Tithonia diversifolia, Embelia sessiliflora, and Combretum indicum were the most commonly used in treatments of infectious diseases. We suggest that these plant species should be the first to be pharmacologically tested for possible development of medicines, and the remaining species registered should subsequently undergo testing.

Traditional Uses of Leguminosae among the Karen in Thailand.

Leguminosae (legumes) are one of the largest plant families. They are widely used for a variety of purposes by people around the world and include many important cultivated economic food crops. On local scales, legumes are commonly used by various ethnic groups. However, the data are incomplete and scattered, not least in Thailand. We found that species of legumes were important in Karen communities, so we decided to investigate in detail the traditional knowledge of legumes on a local scale among Karen people in northern Thailand. We interviewed six herbalists and eighty-four nonherbalist informants in three Karen villages in Chiang Mai province about their use of legumes, and about the local names for the species, using semistructured interviews. A total of 83 legumes species (in 45 genera) had 4443 use reports. Five of the 83 legume species had not been reported previously as used in Thailand. Most Karen use reports (43%) of legumes were for food, medicine (36%), and materials (8%), but in term of species more legumes (68 species) were used for medicine than for food (53 species). The legume genera with most used species were Crotalaria and Flemingia each with six species. The most important species are Tamarindus indica (CI = 3.38), Senegalia rugata (CI = 2.39), Glycine max (CI = 1.27) respectively.

Exotic Plants Used by the Hmong in Thailand.

Exotic species are an integral part of the plants used by many ethnic groups, but they usually receive little attention and have been considered alien to the ethnobotanical data. Here, we analyze the plants used by Thai Hmong refugees that are not native to their current habitats in Thailand. We attempt to understand the sources of this knowledge. Do people maintain the original traditional knowledge related to exotic species when they migrate to a new region, or does new knowledge originate from acculturation? We interviewed 16 specialist Hmong informants in Nan province, Thailand, about their traditional knowledge of 69 exotic species used. Acquisition of this knowledge has a long history; several species are the same as plants used by the Hmong in China and other countries, others are globally useful species which have become part of the pool of species that the Hmong have developed local knowledge about. However, migration also involves the integration of local knowledge from other cultures, and also adapts them to function in urban settings. This includes using closely related exotic taxa that replace some of the species they used in their original homelands. The migrants' traditional knowledge in their new habitats is more complicated and also involves the development of local knowledge that is entirely new.

Important Medicinal Plant Families in Thailand.

Throughout the world, surveys have been conducted at the country level to answer research questions pertaining to ethnomedicinal usage patterns. This study is focused on Thailand, which has never been surveyed systematically in this way. We mined 16,000 records of medicinal plant use from 64 scientific reports, which were published from 1990 to 2014. In total, 2,187 plant species were cited as being useful for medicinal purposes. The overall aim was to reveal the relative importance of the plant families for pharmacological research. To determine the most important medicinal plant families, we use a combination of three statistical approaches: linear regression, Binomial analysis, and Bayesian analysis. At the regional level, 19 plant families repeatedly stood out as being the most important from an ethnomedicinal perspective.