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An increasing number of ecological studies have used chemical diversity as a functionally relevant, scalable measure of phytochemical mixtures, demanding more rigorous attention to how chemical diversity is estimated. Most studies have focused on the composition of phytochemical mixtures and have largely ignored structural concerns, which may have greater importance for ecological function. Here, we explore the development of structural complexity and compositional diversity resulting from different biotic and abiotic interactions in Piper kelleyi Tepe (Piperaceae). We also describe how variation in structural complexity and compositional diversity differs between two congeners, P. kelleyi and P. reticulatum. To better interpret these results, we have developed a framework for interpreting these dimensions of chemical diversity in phytochemical mixtures.We used the tropical shrub, P. kelleyi, as a model system to examine interactions between ecological factors and dimensions of phytochemical diversity. We also compared compositional diversity and metabolic complexity in P. kelleyi and P. reticulatum using liquid chromatography and 1H NMR, respectively, to examine trade‐offs between compositional diversity and structural complexity. A framework is provided to generate meaningful estimates of the structural complexity of phytochemical mixtures as measured by 1H NMR.Piper is an abundant plant genus that supports diverse insect communities throughout the tropics. Subtle changes in understorey forest light were associated with increases in herbivory that directly increased compositional diversity and indirectly decreased structural complexity in P. kelleyi. This was attributed to the production of oxidation products resulting from herbivory‐driven decomposition of structurally complex defence compounds. This type of complex result would remain undetected using standard chemical ecology approaches and accounts for the detailed molecular changes that are likely to affect species interactions.Synthesis. Our quantitative framework provides a method for considering trade‐offs between structural complexity and compositional diversity and the interpretation of analytical approaches for each. This methodology will provide new theoretical insights and a more sophisticated model for examining the ecology and evolution of chemically mediated interactions. [ABSTRACT FROM AUTHOR]

Abstract: Studies of herbivores and secondary consumer communities rarely incorporate a comprehensive characterization of primary producer trait variation, thus limiting our understanding of how plants mediate community assembly of consumers. We took advantage of recent technological developments for efficient generation of phytochemical, microbial and genomic data to characterize individual alfalfa plants (Medicago sativa; Fabaceae) growing in an old‐field, semi‐naturalized state for 770 traits (including 753 chemical features). Using random forest modelling, we investigated the effect of variation in these traits on arthropod and fungal assemblages while accounting for plant genetic structure. We found that traits indicative of plant vigour, including size, percentage of flowering stems and leaf area, were positively associated with arthropod richness and abundance. Most phytochemicals were, by comparison, poor predictors, although phytochemical diversity and several individual phenolic compounds were important. Plants with a higher proportion of flowering stems were hotspots of intertrophic interactions with higher species richness of secondary consumers. The effects of many traits on plant‐associated assemblages were best modelled as nonlinear functions, often incorporating threshold effects. Foliar fungal richness was not well predicted by our models, suggesting we have much to learn regarding the role of plant traits on phyllosphere fungi at small spatial scales. Our results support the need for characterization of multiple axes of plant phenotypes in studies of plant‐arthropod‐microbe communities and demonstrate the value of modern analytical techniques for understanding the nonlinear ways in which plant traits mediate the structure of associated biotic communities. A plain language summary is available for this article. [ABSTRACT FROM AUTHOR]

Abstract: Prenylflavonoids are an unique class of phytochemicals found in the inflorescences of the hop plant (Humulus lupulus). These flavonoids have demonstrated a wide range of biological activities, which may be influenced by their stereochemical configuration. Additionally, recent studies suggest that hop prenylflavonoids are subject to biotransformations which could alter or enrich their stereochemistry. In order to facilitate studies of the stereoisomers of flavanones, a facile method was developed for resolving the diastereomeric esters of flavanones via reversed-phase HPLC. Herein, a method for forming the tri-(1S)-(−)-camphanic acid esters of the 4′,5,7-trihydroxy flavanones naringenin, 8-prenylnaringenin and 6-prenylnaringenin, is described. The respective diastereomers were separated using analytical reversed-phase HPLC. Diastereomeric esters were isolated by preparative HPLC to >98% d.e. based on HPLC, with their absolute configurations established by application of CD spectrometry. [Copyright &y& Elsevier]

Objectives: There are currently no baseline data regarding the amount and types of case reports produced by forensic anthropologists. This research fills that gap by providing data on caseloads of practicing forensic anthropologists and identifying variables that may contribute to amount and type of casework. Materials and methods: A survey was distributed to practicing forensic anthropologists (n = 364) to explore number of case reports written and possible influential factors. Questions included demographic information, employment type, institution where master's degree or PhD were obtained, type of reports written, professional organization membership, certification, graduate research focus, among others. Data were analyzed using summary statistics, a random forest model, network analysis, and structural equation modeling. Results: The mean number of sole‐authored skeletal analysis reports per year was 12.33 and field recovery reports was 2 per year. Statistical analyses identified several variables influencing case loads which included: number of fieldwork reports per year, current employment, total number of cases analyzed, age, publication record, and institution of doctoral degree. Network analyses revealed that individuals in academic settings tended to have a bioarchaeological research focus from their graduate work, whereas those in an applied setting had a focus on forensic anthropology. Further, degree institution influenced employment type. Discussion/conclusions: These data address expectations for the number of cases analyzed by a forensic anthropologist per year and set a baseline for expectations and performance. Based on these results, we suggest that forensic anthropology is underutilized in the medicolegal death investigation system and more forensic anthropologists should be employed within Medical Examiner/Coroner's Offices. [ABSTRACT FROM AUTHOR]

Modern metabolomic approaches that generate more comprehensive phytochemical profiles than were previously available are providing new opportunities for understanding plant‐animal interactions. Specifically, we can characterize the phytochemical landscape by asking how a larger number of individual compounds affect herbivores and how compounds covary among plants. Here we use the recent colonization of alfalfa (Medicago sativa) by the Melissa blue butterfly (Lycaeides melissa) to investigate the effects of indivdiual compounds and suites of covarying phytochemicals on caterpillar performance. We find that survival, development time, and adult weight are all associated with variation in nutrition and toxicity, including biomolecules associated with plant cell function as well as putative anti‐herbivore action. The plant‐insect interface is complex, with clusters of covarying compounds in many cases encompassing divergent effects on different aspects of caterpillar performance. Individual compounds with the strongest associations are largely specialized metabolites, including alkaloids, phenolic glycosides, and saponins. The saponins are represented in our data by more than 25 individual compounds with beneficial and detrimental effects on L. melissa caterpillars, which highlights the value of metabolomic data as opposed to approaches that rely on total concentrations within broad defensive classes. [ABSTRACT FROM AUTHOR]

Modern metabolomic approaches that generate more comprehensive phytochemical profiles than were previously available are providing new opportunities for understanding plant‐animal interactions. Specifically, we can characterize the phytochemical landscape by asking how a larger number of individual compounds affect herbivores and how compounds covary among plants. Here we use the recent colonization of alfalfa (Medicago sativa) by the Melissa blue butterfly (Lycaeides melissa) to investigate the effects of indivdiual compounds and suites of covarying phytochemicals on caterpillar performance. We find that survival, development time, and adult weight are all associated with variation in nutrition and toxicity, including biomolecules associated with plant cell function as well as putative anti‐herbivore action. The plant‐insect interface is complex, with clusters of covarying compounds in many cases encompassing divergent effects on different aspects of caterpillar performance. Individual compounds with the strongest associations are largely specialized metabolites, including alkaloids, phenolic glycosides, and saponins. The saponins are represented in our data by more than 25 individual compounds with beneficial and detrimental effects on L. melissa caterpillars, which highlights the value of metabolomic data as opposed to approaches that rely on total concentrations within broad defensive classes. [ABSTRACT FROM AUTHOR]

Herbivorous insects can defend themselves against pathogens via an immune response, which is influenced by the nutritional quality and phytochemistry of the host plant. However, it is unclear how these aspects of diet interact to influence the insect immune response and what role is played by ingested foliar microbes. We examined dietary protein, phytochemistry, and the caterpillar microbiome to understand variation in immune response of the Melissa blue butterfly, Lycaeides melissa. We also asked if these factors have host plant-specific effects by measuring L. melissa immune response when reared on a recently colonized exotic host plant (Medicago sativa) as compared to the immune response on an ancestral, native host (Astragalus canadensis). L. melissa did not experience immunological benefits directly related to consumption of the novel plant M. sativa. However, we did find negative, direct effects of phytochemical diversity and negative, direct effects of diet-derived microbial diversity on constitutive immune response for caterpillars fed M. sativa, as measured by phenoloxidase activity. Foliar protein did not directly influence the immune response, but did do so indirectly by increasing weight gain. Our results highlight the important effects of host diet on caterpillar physiology and raise the possibility that foliar microbiota, despite being rapidly passed through the gut, can affect the caterpillar immune response. [ABSTRACT FROM AUTHOR]

Intraspecific phytochemical variation across a landscape can cascade up trophic levels, potentially mediating the composition of entire insect communities. Surprisingly, we have little understanding of the processes that regulate and maintain phytochemical variation within species, likely because these processes are complex and operate simultaneously both temporally and spatially. To assess how phytochemistry varies within species, we tested the degree to which resource availability, contrasting soil type, and herbivory generate intraspecific chemical variation in growth and defense of the tropical shrub, Piper imperiale (Piperaceae). We quantified changes in both growth (e.g., nutritional protein, above- and below-ground biomass) and defense (e.g., imide chemicals) of individual plants using a well-replicated fully factorial shade-house experiment in Costa Rica. We found that plants grown in high light, nutrient- and richer old alluvial soil had increased biomass. High light was also important for increasing foliar protein. Thus, investment into growth was determined by resource availability and soil composition. Surprisingly, we found that chemical defenses decreased in response to herbivory. We also found that changes in plant protein were more plastic compared to plant defense, indicating that constitutive defenses may be relatively fixed, and thus an adaptation to chronic herbivory that is common in tropical forests. We demonstrate that intraspecific phytochemical variation of P. imperiale is shaped by resource availability from light and soil type. Because environmental heterogeneity occurs over small spatial scales (tens of meters), herbivores may be faced with a complex phytochemical landscape that may regulate how much damage any individual plant sustains. [ABSTRACT FROM AUTHOR]

To understand the implications of the forensic anthropological practice of "ancestry" estimation, we explore terminology that has been employed in forensic anthropological research. The goal is to evaluate how such terms can often circulate within social contexts as a result, which may center forensic anthropologists as constituting "race" itself through analysis and categorization. This research evaluates terminology used in anthropological articles of the Journal of Forensic Sciences between 1972 and 2020 (n = 314). Terminology was placed into two categories: classifiers and descriptors. Classifiers were standardized into one of five options: "race," "ancestry," "population," "ethnic," or "other." Descriptors included terms used to describe individuals within these classificatory systems. We also compared these terms to those in the NamUs database and the U.S. census. Our results found that the terms "ancestry" and "race" are often conflated and "ancestry" largely supplanted "race" in the 1990s without a similar change in research approach. The NamUs and census terminology are not the same as that used in forensic anthropological research; illustrating a disconnect in the terms used to identify the missing, unidentified, and in social contexts with those used in anthropological research. We provide histories of all of these terms and conclude with suggestions for how to use terminology in the future. It is important for forensic anthropologists to be cognizant of the terms they use in medicolegal contexts, publications, and in public and/or professional spaces. The continued use of misrepresentative and improper language further marginalizes groups and perpetuates oppression rooted in systemic racism. [ABSTRACT FROM AUTHOR]

Foundational hypotheses addressing plant–insect codiversification and plant defense theory typically assume a macroevolutionary pattern whereby closely related plants have similar chemical profiles. However, numerous studies have documented variation in the degree of phytochemical trait lability, raising the possibility that phytochemical evolution is more nuanced than initially assumed. We utilize proton nuclear magnetic resonance (1H NMR) data, chemical classification, and double digest restriction-site associated DNA sequencing (ddRADseq) to resolve evolutionary relationships and characterize the evolution of secondary chemistry in the Neotropical plant clade Radula (Piper; Piperaceae). Sequencing data substantially improved phylogenetic resolution relative to past studies, and spectroscopic characterization revealed the presence of 35 metabolite classes. Metabolite classes displayed phylogenetic signal, whereas the crude 1H NMR spectra featured little evidence of phylogenetic signal in multivariate tests of chemical resonances. Evolutionary correlations were detected in two pairs of compound classes (flavonoids with chalcones; p-alkenyl phenols with kavalactones), where the gain or loss of a class was dependent on the other's state. Overall, the evolution of secondary chemistry in Radula is characterized by strong phylogenetic signal of traditional compound classes and weak phylogenetic signal of specialized chemical motifs, consistent with both classic evolutionary hypotheses and recent examinations of phytochemical evolution in young lineages. [ABSTRACT FROM AUTHOR]

Plant–insect interactions are ubiquitous, and have been studied intensely because of their relevance to damage and pollination in agricultural plants, and to the ecology and evolution of biodiversity. Variation within species can affect the outcome of these interactions. Specific genes and chemicals that mediate these interactions have been identified, but genome‐ or metabolome‐scale studies might be necessary to better understand the ecological and evolutionary consequences of intraspecific variation for plant–insect interactions. Here, we present such a study. Specifically, we assess the consequences of genome‐wide genetic variation in the model plant Medicago truncatula for Lycaeides melissa caterpillar growth and survival (larval performance). Using a rearing experiment and a whole‐genome SNP data set (>5 million SNPs), we found that polygenic variation in M. truncatula explains 9%–41% of the observed variation in caterpillar growth and survival. Genetic correlations among caterpillar performance and other plant traits, including structural defences and some anonymous chemical features, suggest that multiple M. truncatula alleles have pleiotropic effects on plant traits and caterpillar performance (or that substantial linkage disequilibrium exists among distinct loci affecting subsets of these traits). A moderate proportion of the genetic effect of M. truncatula alleles on L. melissa performance can be explained by the effect of these alleles on the plant traits we measured, especially leaf toughness. Taken together, our results show that intraspecific genetic variation in M. truncatula has a substantial effect on the successful development of L. melissa caterpillars (i.e., on a plant–insect interaction), and further point toward traits potentially mediating this genetic effect. [ABSTRACT FROM AUTHOR]