American Journal of Botany最新文献

{"title":"Abortifacients in Mesoamerica and the Southwest United States: Botanical and sociocultural perspectives","authors":"Guadalupe Maldonado Andrade","doi":"10.1002/ajb2.70263","DOIUrl":"10.1002/ajb2.70263","url":null,"abstract":"<p>Throughout colonial history, botanical exploration expanded Western scientific knowledge while reinforcing systems of control, particularly through the erasure of plant knowledge regarding human reproduction issues. Abortifacients, long used by Black and Indigenous communities for fertility regulation and abortion, was among the areas for which traditional knowledge was most frequently silenced. These plants enabled reproductive autonomy and disrupted the colonial agenda of controlling laboring bodies. This synthesis draws heavily from Mexican ethnobotanical practices, and pays equal attention to how these traditions continue, transform, and persist in the U.S. Southwest, particularly among migrants navigating landscapes of legality, stigma, and botanical availability. Drawing on ethnographic fieldwork, community knowledge, and botanical analysis, I examine how abortifacients are used across diasporic and ancestral contexts. The use of plants such as <i>Ruta graveolens</i>, <i>Montanoa tomentosa</i>, and <i>Argemone mexicana</i> reflects continuity and adaptation, blending physical and culturally aligned care. I also address tensions between folk classification and Linnaean taxonomy, the role of privacy in how abortion is named or obscured, and how plant-based care persists where clinical systems fall short. Ultimately, I provide a transborder perspective on reproductive plant knowledge within the context of historical suppression and the contemporary role of cultural plant-based abortion care.</p>","PeriodicalId":7691,"journal":{"name":"American Journal of Botany","volume":"113 9","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ajb2.70263","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148928850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seed-cone architecture of Pararaucaria utahensis Gee, Howell et Dayvault sp. nov. (Cheirolepidiaceae) from the Upper Jurassic Morrison Formation of Utah, USA","authors":"Carole T. Gee,&nbsp;Mariah M. Howell,&nbsp;Richard D. Dayvault","doi":"10.1002/ajb2.70264","DOIUrl":"10.1002/ajb2.70264","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Premise</h3>\u0000 \u0000 <p>Although <i>Pararaucaria</i> seed cones were first described 90 years ago, only in the last dozen years have we discovered the greater extent of the species diversity and paleogeographic range of the genus. <i>Pararaucaria</i> is now known across the mid-latitudes of the Lower Jurassic to Lower Cretaceous in the northern and southern hemispheres. Here we describe a new species, <i>Pararaucaria utahensis</i> Gee, Howell et Dayvault sp. nov. from the Upper Jurassic Morrison Formation in Utah, United States.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>We studied the gross morphology of 12 permineralized cones and used micro-computed tomography (microCT) and three-dimensional visualization to investigate cone architecture and internal structure nondestructively.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Imaging revealed a slender, cylindrical, woody cone axis with a small pith. The scale and bract traces separate near the axis, with the scale trace becoming flattened distally. Three parastichy spirals wrap around the cone, and each bears six pairs of seeds. The ontogenetic development of seeds and bract/scale complexes in this cone species is generally counterclockwise, from apex to base. In nearly all cases, there are two seeds per bract/scale complex. The cone peduncle of one cone bears small <i>Brachyphyllum</i>-type scale leaves.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>In addition to the formal description of a seventh global species of <i>Pararaucaria</i> and the second species in North America, our study of <i>P. utahensis</i> provides clear megafossil evidence for Cheirolepidiaceae in the Upper Jurassic Morrison Formation of western North America. However, the scanty evidence available for the cheirolepidiaceous seed cones in comparison to widespread pollen remains puzzling.</p>\u0000 </section>\u0000 </div>","PeriodicalId":7691,"journal":{"name":"American Journal of Botany","volume":"113 9","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ajb2.70264","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148987823","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydraulic function of medullary bundles in a tropical root climber","authors":"Sandrine Isnard,&nbsp;Damien Longepierre,&nbsp;Taylor Feild","doi":"10.1002/ajb2.70256","DOIUrl":"10.1002/ajb2.70256","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Premise</h3>\u0000 \u0000 <p>Medullary bundles, which are vascular bundles in the pith, have evolved multiple times. However, their functional significance remains poorly understood. Here, we investigated how medullary bundles are involved in the vascular architecture and hydraulic function in a tropical root climber, <i>Adelobotrys scandens</i> (Melastomataceae) to understand the functional significance of this vascular architecture in a wet-adapted root climber species as compared to what is known about medullary bundles in the lineages in hydraulically limited arid/saline environments.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>We used light microscopy to examine the organization of the medullary bundles in the stem. We measured the hydraulic conductivity of intact stems and compared it with those of stems that were experimentally reduced to pith tissue. These analyses allowed estimation of hydraulic conductivity through the pith tissue system.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p><i>Adelobotrys adscendens</i> has a polycyclic eustele, with procambium-derived medullary bundles of two types: peripheric bundles forming leaf traces and cauline bundles forming sympodia at nodal regions of stems. Although the pith has low intrinsic hydraulic conductivity, pith tissues contributed up to 80% of total stem hydraulic conductivity near the apex, before secondary xylem becomes the dominant hydraulic pathway.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>Our experimental study enhances the understanding of atypical vasculature in woody plants. We demonstrated that medullary bundles function in plant water balance, particularly in water transport processes in leaf traces and young shoots, where the pith dominates stem cross-sectional investment. We discuss how this type of vasculature is involved in the evolution of life forms that develop aerial adventitious roots.</p>\u0000 </section>\u0000 </div>","PeriodicalId":7691,"journal":{"name":"American Journal of Botany","volume":"113 9","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ajb2.70256","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148890835","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exposure to heat waves and drought improves subsequent leaf heat tolerance for five oak species in southern California.","authors":"Casey D Wisely, G Olivia Plumb, Mira N Ranganath, Emily Dolida, Ishan Ashford, Graham Luethe, Tim Thibault, Gretchen B North","doi":"10.1002/ajb2.70265","DOIUrl":"https://doi.org/10.1002/ajb2.70265","url":null,"abstract":"<p><strong>Premise: </strong>Given the threats of climate change, we investigated the impact of high temperatures separately and in combination with reduced soil water on leaf heat tolerance for five oaks (Fagaceae) with overlapping ranges in southern California, USA: Quercus agrifolia and Q. chrysolepis (evergreen species), Q. douglasii and Q. lobata (winter-deciduous), and Q. engelmannii (drought-deciduous).</p><p><strong>Methods: </strong>Leaf heat tolerance was measured in two seasons for Q. agrifolia and Q. engelmannii at the Huntington Botanical Gardens, San Marino, California and for container-grown saplings of three other oak species at Occidental College, Los Angeles, California. At both sites, control plants received regular water, and dry plants received one third that amount. Between measurement periods, plants experienced one or more heat waves (each with three or more consecutive days exceeding 32.2°C). For measuring heat tolerance, leaves were submerged in water baths from 20° to 60°C, then dark-adapted chlorophyll fluorescence (F_v/F_m) was measured to assess damage to photosystem II.</p><p><strong>Results: </strong>Leaf heat tolerance differed due to prior heat exposure, soil moisture, leaf habit, and species identity. Leaves under dry conditions were more heat tolerant than under well-watered conditions, and leaves of evergreen species were more tolerant than those of winter-deciduous and drought-deciduous species, as indicated by values of T₅₀, the temperature at which F_v/F_m was reduced by 50%.</p><p><strong>Conclusions: </strong>We suggest that prior exposure to dry conditions and heat waves primed these oaks, particularly the evergreen species, to better endure future heat episodes, at least in the short term.</p>","PeriodicalId":7691,"journal":{"name":"American Journal of Botany","volume":" ","pages":"e70265"},"PeriodicalIF":2.8,"publicationDate":"2026-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148954654","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Success of coastal sage scrub restoration is influenced by local adaptations of shrub species.","authors":"Moises R Perea-Vega, Megan E Lulow, Julie E Coffey, Amy K Henry, Katharina T Schmidt, Priscilla M Ta, Kailen A Mooney, Sarah Kimball","doi":"10.1002/ajb2.70257","DOIUrl":"https://doi.org/10.1002/ajb2.70257","url":null,"abstract":"<p><strong>Premise: </strong>Restoring plant communities is increasingly challenging with climate change. While practitioners have traditionally used local seed sources, many are recommending assisted migration, possibly from more extreme environments such as inland rather than coastal environments, for restoration.</p><p><strong>Methods: </strong>We compared the performance of four dominant Southern California shrub species, grown from seed from either coastal (mean 17.11°C) or inland (mean 19.28°C) populations, in a coastal common garden site under three levels of water availability. The goal was to test whether inland populations had higher survival, growth, and reproduction than coastal populations when experiencing the extreme highs and lows of water availability currently observed inland that mimic possible future climate conditions in coastal regions.</p><p><strong>Results: </strong>Plants of most species generally grew less and had fewer flowers with water reduction, but neither flowering nor growth were strongly or consistently affected by seed source. Within our coastal common garden site, survivorship of coastal-sourced plants was higher than survivorship for inland-sourced plants. An interaction between seed source and water treatment influenced survivorship of all species, such that the negative effect of decreased water was more pronounced for inland-sourced plants. This effect might be explained by the physiological trait measurements which indicated stomatal conductance of Eriogonum and Salvia was higher for inland-sourced populations, suggesting increased water use.</p><p><strong>Conclusions: </strong>Collectively, these findings indicate that the dominant shrub species in this coastal Mediterranean ecosystem are sensitive to reduced water, and assisted migration from inland to coastal environments will not improve restoration outcomes.</p>","PeriodicalId":7691,"journal":{"name":"American Journal of Botany","volume":" ","pages":"e70257"},"PeriodicalIF":2.8,"publicationDate":"2026-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148863484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hemiparasitic Castilleja presence is correlated with increased plant biodiversity across montane plant communities","authors":"Jordan C. Argrett,&nbsp;Makena Lang,&nbsp;Anders Hastings,&nbsp;Y. Anny Chung,&nbsp;Nina Wurzburger,&nbsp;Charles F. Williams","doi":"10.1002/ajb2.70246","DOIUrl":"10.1002/ajb2.70246","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Premise</h3>\u0000 \u0000 <p>Root hemiparasites form haustoria in belowground roots of hosts to extract nutrients and water from the surrounding hosts. Through parasitic symbiosis, these plants disproportionately affect plant communities relative to their abundance by reducing host size, altering nutrient flow, and eventually increasing local biodiversity. Their prevalence and potential as keystone species position hemiparasites as important drivers of community structure.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>In a 2-year study at the Rocky Mountain Biological Laboratory, we selected paired presence and absence plots for three species of hemiparasitic <i>Castilleja</i> across seven study sites to explore the association of <i>Castilleja</i> with differences in the structure of montane plant communities. Our objectives were to (1) observe the relationship between three hemiparasitic <i>Castilleja</i> species and plant community diversity and composition and (2) assess the host range and preference for each species in situ using direct and indirect sampling. Percentage cover of all species was recorded to assess the effect of <i>Castilleja</i> presence on plant community diversity and composition. To assess host range and preference and to support nearest-neighbor and indicator-species analyses, we excavated <i>Castilleja</i> individuals to observe haustorial connections.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Across sites, species, and years, the presence of <i>Castilleja</i> was consistently correlated with increased plant biodiversity and site-specific differences in community composition. Excavations suggested that <i>Castilleja</i> species are generalist hemiparasites with some preference for common, dominant hosts.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>Our results identify a positive relationship between <i>Castilleja</i> presence and local plant community diversity and support the interpretation that these species act as generalist hemiparasites.</p>\u0000 </section>\u0000 </div>","PeriodicalId":7691,"journal":{"name":"American Journal of Botany","volume":"113 8","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ajb2.70246","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148683219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genetic distance and pollinator sharing shape divergence in floral volatiles in closely related dioecious Ficus species","authors":"Xiaoxia Deng,&nbsp;Shuai Liao,&nbsp;Yao Ning,&nbsp;Changqiu Liu,&nbsp;Hui Yu,&nbsp;Finn Kjellberg","doi":"10.1002/ajb2.70245","DOIUrl":"10.1002/ajb2.70245","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Premise</h3>\u0000 \u0000 <p>Floral scent is central to host recognition in the fig–fig wasp mutualism, yet how scent divergence relates to pollinator sharing among closely related dioecious <i>Ficus</i> species remains unclear.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>We analyzed volatile organic compounds (VOCs) from four pairs of closely related <i>Ficus</i> species that have different levels of pollinator sharing (complete, partial, or none). Floral scent profiles were compared using multivariate analyses, and their relationship with genetic distance was evaluated using a Mantel test.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Floral scent profiles differed among species and were shaped by both genetic relatedness and pollinator sharing. Nonmetric multidimensional scaling (NMDS) ordination revealed clear clustering of species based on scent composition, and a PERMANOVA revealed significant interspecific differences, except between <i>F. auriculata</i> and <i>F. oligodon</i>, which share pollinators and have similar VOC profiles. In general, species pairs that share pollinators had greater similarity in scent composition than those that did not, although this pattern was not universal. Floral scent similarity declined with increasing genetic distance (Mantel test: <i>r</i> = −0.39, <i>P</i> = 0.041), indicating that closely related species tend to have more similar scent profiles.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>Floral scent similarity is partly associated with pollinator sharing in closely related <i>Ficus</i> species, but this relationship is not consistent and likely depends on additional factors, including genetic divergence and ecological context. Overall, floral scent variation reflects the combined influence of evolutionary history and ecological processes. Broader taxonomic sampling and functional analyses of pollinator responses are needed to further clarify these relationships.</p>\u0000 </section>\u0000 </div>","PeriodicalId":7691,"journal":{"name":"American Journal of Botany","volume":"113 8","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148719934","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The gardener's dilemma: Biodiversity change in cities and what we can do about it","authors":"Françoise Cardou","doi":"10.1002/ajb2.70250","DOIUrl":"10.1002/ajb2.70250","url":null,"abstract":"&lt;p&gt;Gardeners, whether they live in temperate, tropical, or arid regions, understand the work required to maintain a plant community in a state different from local natural vegetation. Planting, pulling, and propagating are interventions meant to promote species that would otherwise not make it and to curtail better-adapted ones, all to achieve a desired composition and function. Given these costs and benefits, some gardeners choose to deploy elaborate tricks to grow the most exotic bloom, while others expend less effort to grow plant species already well suited to local conditions. In short, gardeners make decisions based on what they want and how hard they are willing to work to make this happen. How does a changing planet affect these calculations?&lt;/p&gt;&lt;p&gt;From climate change to air pollution and land-use change, human activity is shuffling the grand ledger of selection and competition globally (Blowes et al., &lt;span&gt;2019&lt;/span&gt;). Once rare species are now widespread, while once dominant ones are on the decline. Nowhere is this biodiversity change more apparent than in cities, where impervious surfaces and intense human activity create environmental conditions with no historical analog (Ellis et al., &lt;span&gt;2013&lt;/span&gt;). Acting on native and non-native species based on their traits, these selective forces are giving rise to new winners and losers in cities worldwide. When, and how, should homeowners, community groups, municipal biologists and other stewards of urban nature intervene? The recently proposed resist–accept–direct (RAD) framework provides a palette of interventions to choose from (Figure 1; Schuurman et al., &lt;span&gt;2022&lt;/span&gt;). Much like the trade-offs faced by gardeners, this framework raises important questions relevant to all stewards of urban nature about what they want to achieve and how hard they may have to work to reach these goals. Here, I examine potential compromises and highlight key knowledge gaps that ecologists can help fill to support dynamic stewardship of urban nature.&lt;/p&gt;&lt;p&gt;Under the RAD framework, three types of interventions are possible in response to biodiversity change (Schuurman et al., &lt;span&gt;2022&lt;/span&gt;). &lt;i&gt;Resisting&lt;/i&gt; change aims to maintain historical species composition despite new prevailing selective forces. We &lt;i&gt;resist&lt;/i&gt; when we weed non-native species or supplement sparse native tree regeneration. There are also many cases where we &lt;i&gt;accept&lt;/i&gt; biodiversity change. Some non-native species are so fully naturalized that eradication is unrealistic, while the unplanned arrival of more southern species may even be welcomed in the context of climate change (Wallingford et al., &lt;span&gt;2020&lt;/span&gt;). In practice, managers often make informed guesses about which species can establish self-sustaining populations and plant those that provide the functionality that they are looking for such as soil stabilization or fruit production (Almas and Conway, &lt;span&gt;2016&lt;/span&gt;; Aubin et al., &lt;span&gt;2024&lt;/span&gt;); this is ","PeriodicalId":7691,"journal":{"name":"American Journal of Botany","volume":"113 8","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ajb2.70250","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148711160","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Environmentally induced dynamics between intraindividual variation and trait means across vegetative, phenological, and floral traits","authors":"Charlotte Møller,&nbsp;Martí March-Salas,&nbsp;Mar Sobral,&nbsp;Judith Haase,&nbsp;Pieter De Frenne,&nbsp;J. F. Scheepens","doi":"10.1002/ajb2.70244","DOIUrl":"10.1002/ajb2.70244","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Premise</h3>\u0000 \u0000 <p>Intraindividual variation in reiterated structures (e.g., leaves) represents an important dimension of phenotypic variation that contributes to functional diversity and the dynamics of ecological communities. It can be expressed differently across plant traits, but how environmental drivers affect intraindividual variation in different trait types remains unknown.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Here we subjected <i>Galium odoratum</i> to drought and shading treatments with a full-factorial experimental design to investigate environmental induction of intraindividual variation in vegetative, phenological, and floral traits and the dynamic relationships between trait mean responses and their variation.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Intraindividual variation differed in magnitude between trait types, with vegetative traits having the highest variation and floral traits the lowest. Intraindividual variation differed among the environmental treatments with floral traits having the highest variation under control conditions, whereas vegetative traits had the highest amount of variation under the combined drought and early-shading treatment. Relationships between intraindividual variation and trait means varied across most traits and treatments, indicating environmentally induced dynamics in trait expressions.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>Intraindividual variation was environmentally inducible and dynamic depending on the treatment, suggesting that plastic responses in intraindividual variation may be an important component for mechanistic adjustments of plants to environmental stresses.</p>\u0000 </section>\u0000 </div>","PeriodicalId":7691,"journal":{"name":"American Journal of Botany","volume":"113 8","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ajb2.70244","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148683156","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrating developmental and macroevolutionary approaches reveals a staminodial origin of all alternisepalous organs in Caryophyllaceae","authors":"Riley J. Rees,&nbsp;Andrea D. Appleton,&nbsp;John J. Schenk","doi":"10.1002/ajb2.70241","DOIUrl":"10.1002/ajb2.70241","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Premise</h3>\u0000 \u0000 <p>The identity of sterile floral organs in second-whorl, alternisepalous positions within Caryophyllaceae remains contentious, having been described as staminodes, “petaloids,” or petals homologous with those of other Pentapetalae. Limited ingroup and outgroup sampling and floral developmental data and inadequate phylogenetic comparative methods in previous studies have added to this uncertainty. Crucially, staminodes have not been analyzed as discrete characters, leaving their homology with other structures unresolved.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>We reconstructed a chronogram of 775 species using five fossil calibrations for Caryophyllaceae and outgroups. Floral traits of 613 species, including number and position of petal-like structures, staminodes, and stamens, were quantified. Stochastic character mapping estimated ancestral character states and transition rates. Literature reviews provided developmental data to characterize common floral forms; transition models were used to assessed patterns of floral development and evolution.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Staminodes evolved at the root of an apetalous Caryophyllaceae and were maintained throughout the backbone, being lost multiple times and becoming petal-like, especially in the Plurcaryophyllaceae in which a second whorl of stamens evolved in the alternisepalous position through the splitting of the alternisepalous primordia. The Caryophyllaceae crown ancestor likely had a single whorl of antesepalous stamens alternating with alternisepalous staminodes.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>Caryophyllaceae flowers are apetalous: All alternisepalous sterile structures are staminodes. Since their origin, staminodes have subsequently undergone multiple instances of loss, reduction, and elaboration. Their evolutionary history parallels patterns in early angiosperm lineages, making Caryophyllaceae a valuable system for investigating the role of staminodes in floral function and diversification.</p>\u0000 </section>\u0000 </div>","PeriodicalId":7691,"journal":{"name":"American Journal of Botany","volume":"113 8","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ajb2.70241","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148560684","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}