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Oenothera sect. Calylophus is a North American group of 13 recognized taxa in the evening primrose family (Onagraceae) with an evolutionary history that may include independent origins of bee pollination, edaphic endemism, and permanent translocation heterozygosity. Like other groups that radiated relatively recently and rapidly, taxon boundaries within Oenothera sect. Calylophus have remained challenging to circumscribe. In this study, we used target enrichment, flanking noncoding regions, gene tree/species tree methods, tests for gene flow modified for target-enrichment data, and morphometric analysis to reconstruct phylogenetic hypotheses, evaluate current taxon circumscriptions, and examine character evolution in Oenothera sect. Calylophus. Because sect. Calylophus comprises a clade with a relatively restricted geographic range, we were able to extensively sample across the range of geographic, edaphic, and morphological diversity in the group. We found that the combination of exons and flanking noncoding regions led to improved support for species relationships. We reconstructed potential hybrid origins of some accessions and note that if processes such as hybridization are not taken into account, the number of inferred evolutionary transitions may be artificially inflated. We recovered strong evidence for multiple evolutionary origins of bee pollination from ancestral hawkmoth pollination, edaphic specialization on gypsum, and permanent translocation heterozygosity. This study applies newly emerging techniques alongside dense infraspecific sampling and morphological analyses to effectively reconstruct the recalcitrant history of a rapid radiation. [Gypsum endemism; Oenothera sect. Calylophus; Onagraceae; phylogenomics; pollinator shift; recent radiation; target enrichment.]

Nyctaginaceae are one of the most diverse families in core Caryophyllales. The most diagnostic character of the family is a persistent anthocarp derived from a calyx-like perianth. Anthocarp morphology is highly variable across the family, but its evolution is poorly studied. We investigate anthocarp evolution in Nyctaginaceae through extensive anatomical studies (159 species from 28 genera representing six of seven tribes) and phylogenetic character state reconstructions. We found highly diverse anthocarp anatomy across Nyctaginaceae, with most traits analysed evolving multiple times throughout the family. The representatives of three early-diverging clades of Nyctaginaceae (Leucastereae, Boldoeae and Colignonieae) possess a calyx-like anthocarp with simplified anatomy. The so-called ‘glands’ in Nyctagineae and Pisonieae are emergences, whereas wings originate by accrescence of perianth segments, elongation of the ribs and outgrowths (emergences) of anthocarp mesophyll. Anthocarp anatomy can be considered as a generic-level feature in Colignonieae, Pisonieae, Bougainvilleeae and Nyctagineae. The most dramatic transitions from perianth to anthocarp involve the shrivelling and abscission of the upper perianth part and the maintenance of the basal modified perianth portion that originated in the clade comprising Colignonieae and sister clades.

PREMISE Medullary bundles, i.e., vascular units in the pith, have evolved multiple times in vascular plants. However, no study has ever explored their anatomical diversity and evolution within a phylogenetic framework. Here, we investigated the development of the primary vascular system within Nyctaginaceae showing how medullary bundles diversified within the family. METHODS Development of 62 species from 25 of the 31 genera of Nyctaginaceae in stem samples was thoroughly studied with light microscopy and micro-computed tomography. Ancestral states were reconstructed using a maximum likelihood approach. RESULTS Two subtypes of eusteles were found, the regular eustele, lacking medullary bundles, observed exclusively in representatives of Leucastereae, and the polycyclic eustele, containing medullary bundles, found in all the remaining taxa. Medullary bundles had the same origin and development, but the organization was variable and independent of phyllotaxy. Within the polycyclic eustele, medullary bundles developed first, followed by the formation of a continuous concentric procambium, which forms a ring of vascular bundles enclosing the initially formed medullary bundles. The regular eustele emerged as a synapomorphy of Leucastereae, while the medullary bundles were shown to be a symplesiomorphy for Nyctaginaceae. CONCLUSIONS Medullary bundles in Nyctaginaceae developed by a single shared pathway, that involved the departure of vascular traces from lateral organs toward the pith. These medullary bundles were encircled by a continuous concentric procambium that also constituted the polycyclic eustele, which was likely a symplesiomorphy for Nyctaginaceae with one single reversion to the regular eustele.

Funded in 1971 under Title III, Elementary and Secondary Education Act (ESEA), the teacher exchange program to improve reading instruction was designed as a 3 year project. The thrust of the program ranged from creating awareness of and interest in good teaching practices to helping instructors implement these practices in their own classrooms. Building on another ESEA Title III program, planners designed the Upper Cumberland Reading Project to: (1) address the needs of 13 Appalachian countries in Tennessee; (2) demonstrate teaching methods which could be used with basal programs and in self-contained classrooms; (3) require no expenditures for materials or equipment; (4) demonstrate approaches for teaching reading which could be used after the project ended. The actual exchange program had 3 stages: (1) itinerant teachers from the 2 exchange centers spend 1 day visiting participating teachers; (2) during the next 5 days, participating teachers visited the 2 demonstration schools; and (3) on the last 2 days of an exchange, participants returned to their own schools and worked with the ESEA Title III itinerant teachers to implement instructional practices observed at the centers. The 5 findings, measured by the Stanford Achievement Test, indicated that the ESEA Title III pupils made significantly greater gains in reading than did control pupils. (KM)

This study surveyed evaluation and dissemination/diffusion practices of ESEA III projects funded in the 1969 fiscal year, which projects are nearing the end of their operations as federally supported programs. The study attempted to discover if (1) the projects were evaluated in accordance with generally accepted procedures, (2) the project results were widely and effectively disseminated and diffused, (3) there was an association between the degrees to which projects were adequately evaluated and effectively disseminated, and (4) there was an association between the adequacy of projects' evaluation-dissemination components and program continuance at the end of Title III ESEA funding. Two questionnaires were mailed to each of approximately 300 projects listed in an index of programs approved in fiscal year 1969. One instrument sought information about process and product evaluation activities and the other about dissemination and diffusion. The report analyzes the returns, draws conclusions, and makes recommendations. (Author/JF)

Anulocaulis, commonly known as “ringstem,” is a small, unusual genus restricted to the Chihuahuan, Sonoran, and Mojave deserts of North America. Here we combined light microscopy and histochemical tests to characterize for the first time the “sticky structures” (here called secretory rings) found on the stem internodes of Anulocaulis. The secretory rings were shown to be groups of epidermal cells, or unicellular glandular trichomes, which largely differ from their neighboring cells both in structure and histochemistry. The cells start to differentiate in early stages of stem development. They begin as regular epidermal cells, but later their anticlinal and external tangential walls start to enlarge. At maturity the cells become remarkably elongated, even balloon-like, with dense cytoplasmic content. Although the secretory rings have been reported as “mucilaginous structures” based on morphological observations, preliminary histochemical analyses showed that its exudate is complex, including a mixture of mucilage, proteins, and phenolic compounds. Future investigations are needed to compare the anatomy of the secretory rings within related genera of Nyctaginaceae and characterize the chemical components of their exudate more specifically to search for potential homologies and adaptive functions of these structures.

The Caryophyllales includes 40 families and 12,500 species, representing a large and diverse clade of angiosperms. Collectively, members of the clade grow on all continents and in all terrestrial biomes and often occupy extreme habitats (e.g., xeric, salty). The order is characterized by many taxa with unusual adaptations including carnivory, halophytism, and multiple origins of C4 photosynthesis. However, deep phylogenetic relationships within the order have long been problematic due to putative rapid divergence. To resolve the deep-level relationships of Caryophyllales, we performed phylogenomic analyses of all 40 families of Caryophyllales. We time-calibrated the molecular phylogeny of this clade, and evaluated putative correlations among plastid structural changes and rates of molecular substitution. We recovered a well-resolved and well-supported phylogeny of the Caryophyllales that was largely congruent with previous estimates of this order. Our results provide improved support for the phylogenetic position of several key families within this clade. The crown age of Caryophyllales was estimated at ca. 114.4 million years ago (Ma), with periods of rapid divergence in the mid-Cretaceous. A strong, positive correlation between nucleotide substitution rate and plastid structural changes was detected. Our study highlights the importance of broad taxon sampling in phylogenomic inference and provides a firm basis for future investigations of molecular, morphological, and ecophysiological evolution in Caryophyllales.

Oenothera sect. Calylophus is a North American group of 13 recognized taxa in the evening primrose family (Onagraceae) with an evolutionary history that may include independent origins of bee pollination, edaphic endemism, and permanent translocation heterozygosity. Like other groups that radiated relatively recently and rapidly, taxon boundaries within Oenothera sect. Calylophus have remained challenging to circumscribe. In this study, we used target enrichment, flanking non-coding regions, summary coalescent methods, tests for gene flow modified for target-enrichment data, and morphometric analysis to reconstruct phylogenetic hypotheses, evaluate current taxon circumscriptions, and examine character evolution in Oenothera sect. Calylophus. Because sect. Calylophus comprises a clade with a relatively restricted geographic range, we were able to extensively sample across the range of geographic and morphological diversity in the group. We found that the combination of exons and flanking non-coding regions led to improved support for species relationships. We reconstructed potential hybrid origins of some accessions and note that if processes such as hybridization are not taken into account, the number of inferred evolutionary transitions may be artificially inflated. We recovered strong evidence for multiple origins of the evolution of bee pollination from ancestral hawkmoth pollination, the evolution of edaphic specialization on gypsum, and permanent translocation heterozygosity. This study applies newly emerging techniques alongside dense infraspecific sampling and morphological analyses to effectively address a relatively common but recalcitrant problem in evolutionary biology.

SummaryThe role whole genome duplication (WGD) plays in the history of lineages is actively debated. WGDs have been associated with advantages including superior colonization, various adaptations, and increased effective population size. However, the lack of a comprehensive mapping of WGDs within a major plant clade has led to uncertainty regarding the potential association of WGDs and higher diversification rates.Using seven chloroplast and nuclear ribosomal genes, we constructed a phylogeny of 5,036 species of Caryophyllales, representing nearly half of the extant species. We phylogenetically mapped putative WGDs as identified from analyses on transcriptomic and genomic data and analyzed these in conjunction with shifts in climatic niche and lineage diversification rate.Thirteen putative WGDs and twenty-seven diversification shifts could be mapped onto the phylogeny. Of these, four WGDs were concurrent with diversification shifts, with other diversification shifts occurring at more recent nodes than WGDs. Five WGDs were associated with shifts to colder climatic niches.While we find that many diversification shifts occur after WGDs it is difficult to consider diversification and duplication to be tightly correlated. Our findings suggest that duplications may often occur along with shifts in either diversification rate, climatic niche, or rate of evolution.

Genetic factors such as decreased genetic diversity and increased homozygosity can have detrimental effects on rare species, and may ultimately limit potential adaptation and exacerbate population declines. The Gulf and Atlantic Coastal Plain physiographic region has the second highest level of endemism in the continental USA, but habitat fragmentation and land use changes have resulted in catastrophic population declines for many species. Astragalus michauxii (Fabaceae) is an herbaceous plant endemic to the region that is considered vulnerable to extinction, with populations generally consisting of fewer than 20 individuals. We developed eight polymorphic microsatellites and genotyped 355 individuals from 24 populations. We characterized the population genetic diversity and structure, tested for evidence of past bottlenecks, and identified evidence of contemporary gene flow between populations. The mean ratios of the number of alleles to the allelic range (M ratio) across loci for A. michauxii populations were well below the threshold of 0.68 identified as indicative of a past genetic bottleneck. Genetic diversity estimates were similar across regions and populations, and comparable to other long-lived perennial species. Within-population genetic variation accounted for 92 % of the total genetic variation found in the species. Finally, there is evidence for contemporary gene flow among the populations in North Carolina. Although genetic factors can threaten rare species, maintaining habitats through prescribed burning, in concert with other interventions such as population augmentation or (re)introduction, are likely most critical to the long term survival of A. michauxii.

Microsatellites, or simple sequence repeats (SSRs), have long played a major role in genetic studies due to their typically high polymorphism. They have diverse applications, including genome mapping, forensics, ascertaining parentage, population and conservation genetics, identification of the parentage of polyploids, and phylogeography. We compare SSRs and newer methods, such as genotyping by sequencing (GBS) and restriction site associated DNA sequencing (RAD-Seq), and offer recommendations for researchers considering which genetic markers to use. We also review the variety of techniques currently used for identifying microsatellite loci and developing primers, with a particular focus on those that make use of next-generation sequencing (NGS). Additionally, we review software for microsatellite development and report on an experiment to assess the utility of currently available software for SSR development. Finally, we discuss the future of microsatellites and make recommendations for researchers preparing to use microsatellites. We argue that microsatellites still have an important place in the genomic age as they remain effective and cost-efficient markers.

Establishing the phylogenetic and demographic history of rare plants improves our understanding of mechanisms that have led to their origin and can lead to valuable insights that inform conservation decisions. The Atlantic coastal plain of eastern North America harbours many rare and endemic species, yet their evolution is poorly understood. We investigate the rare Sandhills lily (Lilium pyrophilum), which is endemic to seepage slopes in a restricted area of the Atlantic coastal plain of eastern North America. Using phylogenetic evidence from chloroplast, nuclear internal transcribed spacer and two low-copy nuclear genes, we establish a close relationship between L. pyrophilum and the widespread Turk's cap lily, L. superbum. Isolation-with-migration and coalescent simulation analyses suggest that (i) the divergence between these two species falls in the late Pleistocene or Holocene and almost certainly post-dates the establishment of the edaphic conditions to which L. pyrophilum is presently restricted, (ii) vicariance is responsible for the present range disjunction between the two species, and that subsequent gene flow has been asymmetrical and (iii) L. pyrophilum harbours substantial genetic diversity in spite of its present rarity. This system provides an example of the role of edaphic specialization and climate change in promoting diversification in the Atlantic coastal plain.

Recent phylogenetic work shows that existing tribal concepts within Nyctaginaceae are incompatible with the principle of recognizing monophyletic taxa. We review the history of supergeneric classification in Nyctaginaceae, clarify issues pertaining to priority of certain generic names, and discuss the application of the conserved family name to the tribe Nyctagineae. Pisoniella and Phaeoptilum are moved from tribe Nyctagineae to Pisonieae and Bougainvilleeae, respectively, while tribe Abronieae, containing Abronia and Tripterocalyx, is submerged into Nyctagineae. Two distinctive genera, Caribea and Colignonia, are assigned to their own tribes, recognizing both their uniqueness and the uncertainty of their phylogenetic relationships. Finally, subtribes are not recognized in tribe Nyctagineae. Updated descriptions are provided for each tribe and one new tribe, Caribeaeae Douglas & Spellenberg, is recognized. Plant habit and general geographic distribution seem to be at least as pertinent as the often-homoplasious morphological details which had been emphasized in previous classifications.

Recent phylogenetic work has demonstrated that the ability of species of the angiosperm family Nyctaginaceae to self-fertilize is evolutionarily labile. However, the potential for further investigation of the evolution of mating systems in the family is limited, because there is no information on reproductive biology for several genera. I performed an experiment on a natural population of Tripterocalyx carneus to determine whether this species is self-compatible. Individual flowers were emasculated, bagged to exclude pollinators, or both. Flowers that were bagged but not emasculated set viable fruit in the majority of cases, which demonstrates that this species is self-compatible.

Premise of the study: The One Thousand Plant Transcriptomes Project (1KP, 1000+ assembled plant transcriptomes) provides an enormous resource for developing microsatellite loci across the plant tree of life. We developed loci from these transcriptomes and tested their utility. Methods and Results: Using software packages and custom scripts, we identified microsatellite loci in 1KP transcriptomes. We assessed the potential for cross-amplification and whether loci were biased toward exons, as compared to markers derived from genomic DNA. We characterized over 5.7 million simple sequence repeat (SSR) loci from 1334 plant transcriptomes. Eighteen percent of loci substantially overlapped with open reading frames (ORFs), and electronic PCR revealed that over half the loci would amplify successfully in conspecific taxa. Transcriptomic SSRs were approximately three times more likely to map to translated regions than genomic SSRs. Conclusions: We believe microsatellites still have a place in the genomic age—they r...

The general phylogeographical paradigm for eastern North America (ENA) is that many plant and animal species retreated into southern refugia during the last glacial period, then expanded northward after the last glacial maximum (LGM). However, some taxa of the Gulf and Atlantic Coastal Plain (GACP) demonstrate complex yet recurrent distributional patterns that cannot be explained by this model. For example, eight co-occurring endemic plant taxa with ranges from New York to South Carolina exhibit a large disjunction separating northern and southern populations by300 km. Pyxidanthera (Diapensiaceae), a plant genus that exhibits this pattern, consists of two taxa recognized as either species or varieties. We investigated the taxonomy and phylogeography of Pyxidanthera using morphological data, cpDNA sequences, and amplified fragment length polymorphism markers. Morphological characters thought to be important in distinguishing Pyxidanthera barbulata and P. brevifolia demonstrate substantial overlap with no clear discontinuities. Genetic differentiation is minimal and diversity estimates for northern and southern populations of Pxyidanthera are similar, with no decrease in rare alleles in northern populations. In addition, the northern populations harbour several unique cpDNA haplotypes. Pyxidanthera appears to consist of one morphologically variable species that persisted in or near its present range at least through the latter Pleistocene, while the vicariance of the northern and southern populations may be comparatively recent. This work demonstrates that the refugial paradigm is not always appropriate and GACP endemic plants, in particular, may exhibit phylogeographical patterns qualitatively different from those of other ENA plant species.

Describes how school districts with even a modest budget can improve their public relations by giving someone in the district the responsibility to act as a liaison between the school district and the news media. (Author/DN)

This paper challenges the long held hypothesis that insider trading is a victimless crime. Using utility maximization analysis, the author examines both the good news and bad news cases. Injury is demonstrated. Separability of the insider's trade from the insider's information monopoly is also examined utilizing the generally accepted market structure analysis. Separability is rejected.

There was a curious little episode here. Oscar Wilde had arrived in Naples and was staying with his young friend1 on the Posilipo [sic]2 (? Villa Giudice).3 This came to the ears of Matilda Serao, a literary woman who, with Scarfoglio, edited the Mattino newspaper. Somehow or other she also heard of my building the Villa Maya, and of Campo Alegre’s arrival there in a shattered state of health. The first indication we had of this was when Rolfe, the Consul-General, sent me a cutting from the Mattino and said he had already written to rectify the blunder. From the cutting it appeared that Matilda had confused Campo Alegre with Wilde, and me — owing to a similarity of name — with his friend. She spoke of the arrival of Wilde at the Villa Maya, which she described as having been built by this friend, and added that Wilde must have been disgracefully treated in his English prison, as he could hardly stand on his legs. Even Rolfe’s letter did not quite convince Matilda, for she came out with a second ommunication entitled C’e o non c’ e — is it (Wilde) or is it not? I forget how the affair ended.