Spur Length Research Articles

Is pollen limitation linked to phenotypic selection on floral traits in the carnivorous plant Pinguicula moranensis (Lentibulariaceae)?

AbstractIn carnivorous plants, the fitness impacts of phenotypic variation in traits involved in prey attraction and capture have been well documented. However, floral traits could also contribute to the fitness of carnivorous plants. Pinguicula moranensis is a carnivorous plant that presents colorful zygomorphic flowers, which suggests some degree of specialization in its interactions with pollinators. We first tested pollen limitation experimentally by comparing the fruit set in plants that were manually cross‐pollinated with those that were pollinated naturally. Then, using a path analysis approach, we explored the effects of plant size and floral traits (corolla shape, corolla size, spur length, nectar guide size, and stalk length) on fitness (seed number per fruit). We performed two independent path analyses—one with the naturally pollinated plants and the other with the hand pollinated plants—to consider the impacts of these variables with and without the pressure of pollinator attraction. We expected stronger selection on floral traits in naturally pollinated plants. We found evidence of pollen limitation in the fruit set of the naturally pollinated group, suggesting that pollinator availability could impose selective pressures. The path analyses showed a marked direct positive effect of rosette size on plant fitness in both groups. The direct effects of all floral traits had similar magnitudes between the naturally pollinated and hand pollinated plants, except for corolla shape that showed higher coefficients in the first group. Thus, although we evidenced pollen limitation, our prediction about the role of pollinators as selective agents of floral traits in P. moranensis was barely supported.

Nocturnal moth pollination in an alpine orchid, Platanthera tipuloides

AbstractPollination success of alpine plants is often restricted by low and unpredictable pollinator activity because of harsh and unstable weather conditions, where nocturnal pollination is rare. The alpine orchid, Platanthera tipuloides (Orchidaceae), has inconspicuous greenish yellow flowers with a sweet scent and a long spur that contains nectar. These floral traits are expected to be related to nocturnal moth pollination. To elucidate the pollination mode and reproductive characteristics of this species, we measured floral traits (spur length, nectar content in the spur, floral scent), documented flower visitors using camera traps, and quantified self‐compatibility and the degree of pollen limitation through controlled pollinations at two study plots in the Taisetsu Mountains, northern Japan. It was revealed that P. tipuloides is self‐incompatible and pollen limitation was absent at one of the study plots. The flowers emitted more volatile substances during the night, including lilac aldehyde isomers, which are known to attract moths. A nocturnal moth, Entephria amplicosta, was observed foraging nectar from the flowers, while no diurnal visitors were observed. The proboscis of E. amplicosta was shorter than the spur length, but it was long enough to access the accumulated nectar in the spurs. These results suggest that nocturnal pollination by moths is possible and can be efficient even in an alpine ecosystem with harsh environmental conditions.

Calcaneal and dorsal spur morphological and morphometric measurements; 'A radiological study'

Aim: The foot is one of the most neglected parts of our body. One of the causes of foot pain is the plantar calcaneal spur (PCS), which is the bone protrusion formed under the calcaneal bone, and the dorsal spur (DS), which is seen dorsal to the calcaneus. Our study aimed to examine PCS and DS morphologically. Materials and Methods: 235 patients with PCS were included in this retrospective study. Plantar calcaneal spur length (PCSL), plantar calcaneal spur thickness (PCST), Fowler-Philip angle (FPA), and plantar calcaneal fat tissue thickness (PCFT) with radiology in patients with the calcaneal spur, and also to classify plantar calcaneal spur (PCS) and dorsal spur (DS). Results: Bilateral PCS was found in 57.4% of the patients. DS was found in 43.5% of the patients with right PCS and 40.3% of the patients with left PCS. Large DS types were found at a higher level in males than females. Right PCFT was found to be significantly higher in patients with PCS compared to the control group (p=0.034). Conclusion: It was concluded that the majority of PCS patients had bilateral PCS, DS could be seen and there was a strong correlation between PCSL and PCST.

Genetic Foundation of Male Spur Length and Its Correlation with Female Egg Production in Chickens.

Spurs, which mainly appear in roosters, are protrusions near the tarsometatarsus on both sides of the calves of chickens, and are connected to the tarsometatarsus by a bony core. As a male-biased morphological characteristic, the diameter and length of spurs vary significantly between different individuals, mainly related to genetics and age. As a specific behavior of hens, egg-laying also varies greatly between individuals in terms of traits such as age at first egg (AFE), egg weight (EW), and so on. At present, there are few studies on chicken spurs. In this study, we investigated the inheritance pattern of the spur trait in roosters with different phenotypes and the correlations between spur length, body weight at 18 weeks of age (BW18), shank length at 18 weeks of age (SL18), and the egg-laying trait in hens (both hens and roosters were from the same population and were grouped according to their family). These traits related to egg production included AFE, body weight at first egg (BWA), and first egg weight (FEW). We estimated genetic parameters based on pedigree and phenotype data, and used variance analysis to calculate broad-sense heritability for correcting the parameter estimation results. The results showed that the heritability of male left and right spurs ranged from 0.6 to 0.7. There were significant positive correlations between left and right spur length, BW18, SL18, and BWA, as well as between left and right spur length and AFE. We selected 35 males with the longest spurs and 35 males with the shortest spurs in the population, and pooled them into two sets to obtain the pooled genome sequencing data. After genome-wide association and genome divergency analysis by FST, allele frequency differences (AFDs), and XPEHH methods, we identified 7 overlapping genes (CENPE, FAT1, FAM149A, MANBA, NFKB1, SORBS2, UBE2D3) and 14 peak genes (SAMD12, TSPAN5, ENSGALG00000050071, ENSGALG00000053133, ENSGALG00000050348, CNTN5, TRPC6, ENSGALG00000047655,TMSB4X, LIX1, CKB, NEBL, PRTFDC1, MLLT10) related to left and right spur length through genome-wide selection signature analysis and a genome-wide association approach. Our results identified candidate genes associated with chicken spurs, which helps to understand the genetic mechanism of this trait and carry out subsequent research around it.

Evaluation of Anterior Scleral Thickness and Angle Parameters in Eyes with Pseudoexfoliation Syndrome and Glaucoma.

The relationship between anterior scleral thickness (AST) and scleral spur (SS) length was disrupted in eyes with pseudoexfoliation (PX), and SS length was shorter in eyes with pseudoexfoliative glaucoma (PXG). To evaluate AST in eyes with PX and to examine the relationship between AST and Schlemm canal (SC), trabecular meshwork (TM), and SS. Thirty-eight patients with PX syndrome (PXS), 38 patients with PXG, and 38 healthy patients were included in the study. Using sweep source anterior segment optical coherence tomography, AST (0, 1, 2, and 3mm from the SS), SC, and TM were visualized in the nasal and temporal areas, and measurements were compared between groups. The relationships between corneal thickness, TM, SS, SC, and AST were then evaluated. In all groups, the AST, SC, and TM measurements were similar ( P > 0.05). In the PXG group, SS lengths in the temporal area were shorter than those in the control and PXS groups ( P = 0.012). There were significant correlations between TM length and AST in the PXG group ( P < 0.05). The SS length exhibited moderately positive correlations with SC length and mean TM thickness in the PXG ( P < 0.05). There was a significant relationship between AST0 and SS in healthy eyes ( P < 0.05), but not in other eyes. The shorter SS length observed in eyes with PXG may be a sign of structural changes. In addition, disruption of the relationship between AST and SS may be an early sign of pathologic processes, especially in eyes with PXS, and may require closer follow-up of these eyes.

Clinical Study of a Four-Step Program for the Treatment of Plantar Fasciitis with Bone Spurs.

The most common causes of plantar and heel pain are plantar fasciitis and calcaneal spurs, and they often co-exist. Surgery is a recognized treatment for refractory plantar fasciitis. However, few studies have proposed treatment options for patients with metatarsophalangeal fasciitis with bone spurs. Accordingly, this study's purpose was to propose a four-step surgical regimen, and to improve the surgical outcome of plantar fasciitis with osteophytes and to establish a procedure for surgical treatment. Retrospective analysis of 45 patients suffering from plantar fasciitis with bone spurs from 2020 to 2023. All patients underwent a four-step procedure, including plantar fascia release, calcaneal spur grinding, inflammatory tissue removal, and calcaneal burr decompression. The imaging parameters and functional scores were recorded before and after the operation. The objective evaluation included the measurement of calcaneal spur length on radiographs. Clinical evaluation included the American Orthopaedic Foot and Ankle Society (AOFAS), the Visual Analog Scale (VAS), and the Foot and Ankle Outcome Scale (FAOS). Measurement data that conformed to normal distribution were expressed as (x2 ± s), and pre-and postoperative AOFAS, FAOS, and VAS scores were compared using repeated-measures ANOVA, and preoperative and postoperative spur lengths were compared using paired t-tests. The 45 patients were followed up for 3 to 30 months, (17.72 ± 8.53) months, at final follow-up, the patient's AOFAS score improved from preoperative (74.93 ± 5.56) to (94.78 ± 3.98), FAOS score increased from preoperative (76.42 ± 3.37) to (96.16 ± 2.74), the VAS score decreased from (3.18 ± 0.54) to (1.07 ± 1.20) (p < 0.05), the length of spur decreased from (0.72 ± 1.81) cm to (0.23 ± 1.19) cm, and there were significant differences before and after operation (p < 0.05). The four-step surgical regimen is an appropriate and effective surgical procedure to treat plantar fasciitis with bone spurs.

What are the drivers of female success in food-deceptive orchids?

A large suite of floral signals, and environmental and biotic characteristics influence the behavior of pollinators, affecting the female success of food-deceptive orchids. In this study, we examined the many factors shaping the reproductive output of three orchid taxa: Dactylorhiza majalis, D. incarnata var. incarnata, and D. fuchsii. We applied a statistical model to correlate female success (number of fruit sets) with individual characteristics (plant and inflorescence height, number of flowers, and spur length), number of pollinaria removed, flowering time, and density of floral units of co-flowering rewarding plants. Our findings suggested that the broad spectrum of variations in Dactylorhiza's morphological traits, floral display, and flowering phenology within different environmental contexts has a significant impact on their reproductive success. The number of fruits increased with an increase in the number of pollinaria removed in the studied Dactylorhiza taxa. In contrast, a higher number of flowers per inflorescence and higher inflorescences in relation to individual height always decreased fruit set. We observed that low number of co-flowering rewarding plants in populations could affect the Dactylorhiza reproductive output as magnets and competitor plants. The synchronization of flowering, or lack thereof, between Dactylorhiza and rewarding plants can limit reproductive success. This demonstrates that the food deception strategy is multidirectional, and reproductive output can vary considerably both spatially and temporally within the context of this strategy.

We know very little about pollination in the Platanthera Rich (Orchidaceae: Orchidoideae).

The Platanthera Rich. (Orchidoideae) comprise a speciose genus of orchids primarily in the northern hemisphere, with up to 200 known species worldwide. Individual species are known to self-pollinate, but many rely on insect pollinators with characteristics such as floral color, timing of floral odor emissions, nectar rewards, and spur length associated with particular pollination syndromes. As with many orchids, some orchid-pollinator associations are likely highly co-evolved, but we also know that some Platanthera spp. are the result of hybridization events, which implies a lack of pollinator fidelity in some cases. Some Platanthera spp. occur in large numbers which, coupled with the numerous Platanthera-pollinator systems, make them accessible as study species and useful for co-evolutionary studies. Due to the likely effects of climate change and ongoing development on Platanthera spp. habitats, these orchids and their associated pollinators should be a focus of conservation attention and management. However, while there is a fairly substantial literature coverage of Platanthera-pollinator occurrence and interactions, there are still wide gaps in our understanding of the species involved in these systems. In this systematic review, we outline what is current knowledge and provide guidance on further research that will increase our understanding of orchid-insect co-evolutionary relationships. Our review covers 157 orchid species and about 233 pollinator species interacting with 30 Platanthera spp. We provide analyses on aspects of these interactions such as flower morphology, known insect partners of Platanthera species, insect-Platanthera specificity, pollination visitor timing (diurnal vs. nocturnal), floral rewards, and insect behavior affecting pollination outcomes (e.g., pollinia placement). A substantial number of Platanthera spp. and at least a few of their known pollinators are of official (IUCN) conservation concern - and many of their pollinators remain unassessed or even currently unknown - which adds to the urgency of further research on these co-evolved relationships.

Complex floral morphology and scent chemistry mediate hawkmoth pollination of an African orchid in the diverse Habenaria clade

Abstract One explanation for the evolution of complex floral morphology in orchids is that it can function as a component of ‘lock-and-key’ mechanisms that ensure pollen transfer by specific flower visitors. We investigated the roles of floral morphology and scent in the pollination of Bonatea antennifera, an African orchid that is phylogenetically embedded in the hyper-diverse Habenaria clade. Using camera traps and direct observations, we established that B. antennifera is pollinated by an assemblage of short-tongued hawkmoths with proboscides ~4 cm in length, corresponding to the spur length of the orchid. Pollinaria are attached between the palps of these hawkmoths via an intricate mechanism involving a wedge-shaped rostellum chamber and a tooth in the floral spur that deflect the head and proboscis of the hawkmoth to either side of the spur entrance. This functional subdivision of the flower results in removal of a single pollinarium per visit. Scent production is synchronized with the peak activity of hawkmoths at dusk, and electrophysiology experiments showed that hawkmoth antennae respond to several of the dominant volatile terpenoid compounds [e.g. R-(−)-linalool, caryophyllene epoxide, and (E)-nerolidol] emitted by the flowers. These results illustrate the functional significance of complex floral morphology and scent for pollen transfer in orchids.

Morphometric differentiation of three chicken ecotypes of Ethiopia using multivariate analysis.

Twenty-one morphometric traits were measured on 770 extensively managed indigenous chickens in the western zone of Tigray, comprising 412 hens and 358 cocks in three agro-ecologies. The quantitative traits for male and female chicken ecotypes were separately analyzed using multivariate analysis with SAS 2008. Four and seven principal components accounted for about 74.26% and 69.77% of the total variability in morphometric traits for males and females, respectively. Earlobe length, wingspan, skull length, and shank length werethe most important traits for discriminating among female chicken ecotypes, while wingspan, neck length, earlobe length, spur length, body length, and shank length were the most important discriminatory traits among male chicken ecotypes. The discriminant analysis accurately classified 97.3% of female and 100% of male chicken ecotypes. Cluster analysis revealed the genetic heterogeneity of indigenous chicken populations in both sexes. This finding suggests the presence of morphological variations among the indigenous chicken populations in the different agro-ecological zones, classified as distinct indigenous chicken ecotypes (Lowland, Midland, and Highland). Further DNA-based studies are needed to confirm and complement these morphological variations for effective conservation and the development of sustainable genetic improvement strategies for indigenous chicken populations in the region.

Two Growing-Season Warming Partly Promoted Growth but Decreased Reproduction and Ornamental Value of Impatiens oxyanthera.

Climate warming profoundly affects the vegetative growth, flowering phenology and sexual reproduction of plants; therefore, it affects the ornamental value of wild flowers. Despite this, the extent and mechanism of the impact remain unclear. Here, we conducted a warming experiment for two growing seasons (increases of 1.89 °C in 2017 and 2.37 °C in 2018) with infrared heaters to examine the effects of warming on the ornamental value of the wild flower Impatiens oxyanthera, endemic to China, in Mount Emei. We evaluated the comprehensive ornamental value based on plant morphology and flowering characteristics using the analytic hierarchy process (AHP) and disentangled the impact of the two traits on ornamental value using principal component analysis (PCA) and the partial least squares structural equation model (PLS-SEM) under ambient and warming treatments. We hypothesized that warming would reduce the ornamental value of I. oxyanthera in terms of plant morphology and flowering traits. Our results showed that warming significantly decreased plant height and crown width and increased branch number and single-leaf area. Warming also decreased vexillum length, corolla tube length, nectar spur length and pedicel length. In addition, warming shortened flowering duration per plant and reduced flower number, while there was no significant effect on flower longevity and flower color at full-bloom stage between the control and warming treatment. Therefore, the comprehensive ornamental value under warming was lower than that under the control. Pedicel length, flower color, flower longevity and flowering duration per plant were the main factors affecting the comprehensive ornamental value. The PLS-SEM showed that warming had an indirect negative effect on ornamental value via direct negative effects on flowering traits. Collectively, these results indicate that, although promoting vegetative growth, short-term warming significantly decreased the ornamental value of I. oxyanthera due to warming-caused smaller flowers and shorter flowering duration.

The cellular and molecular basis of the spur development in Impatiens uliginosa.

The nectar spur is an important feature of pollination and ecological adaptation in flowering plants, and it is a key innovation to promote species diversity in certain plant lineages. The development mechanism of spurs varies among different plant taxa. As one of the largest angiosperm genera, we have little understanding of the mechanism of spur development in Impatiens. Here, we investigated the initiation and growth process of spurs of Impatiens uliginosa based on histology and hormone levels, and the roles of AUXIN BINDING PROTEIN (ABP) and extensin (EXT) in spur development were explored. Our results indicate that the spur development of I. uliginosa is composed of cell division and anisotropic cell elongation. Imbalances in spur proximal-distal cell division lead to the formation of curved structures. Endogenous hormones, such as auxin and cytokinins, were enriched at different developmental stages of spurs. IuABP knockdown led to an increase in spur curves and distortion of morphology. IuEXT knockdown resulted in reduced spur length and loss of curve and inner epidermal papillae structures. This study provides new insights into the mechanism of spur development in core eudicots.

The anterior scleral thickness in primary open-angle glaucoma with high myopia.

This study aimed to investigate and compare the anterior scleral thickness (AST) among high myopia (HM), primary open-angle glaucoma (POAG), and POAG with HM (HMPOAG) groups. Thirty-two HM eyes, 30 POAG eyes, and 31 HMPOAG eyes were included. The Schlemm's canal (SC) area, trabecular meshwork (TM) thickness, scleral spur (SS) length, and AST were measured using swept-source optical coherence tomography. AST was measured at 0 mm (AST0), 1 mm (AST1), 2 mm (AST2), and 3 mm (AST3) from SS. The HMPOAG group had significantly thinner AST, SS length, and TM thickness than the HM and POAG groups (all p < 0.05). In addition, the SC area of the HMPOAG group was also significantly smaller than that of the HM group (p < 0.001). The HMPOAG group had the thinnest AST, shortest SS, thinnest TM, and smallest SC. The thinnest AST might contribute to the shortest SS, and further to the thinnest TM and smallest SC in the HMPOAG group. AST might be a novel clinical indicator in the prediction and evaluation of POAG.

Morphological characterization and screening of Impatiens wild species for heat tolerance

Impatiens sp. is an annual plant that flowers all year round. High temperature stress is a major challenge limiting crop productivity. The research was conducted at experiment garden in Palasari Cipanas, BRIN, Indonesia, at an altitude of 1000 ASL, from January - April 2023. The aim of the research was to explore the morphological variation of Impatiens wild species and to obtain some heat tolerance accession for next breeding program. Twenty nine accession of Impatiens were observed for the qualitative and quantitative data including the evaluation of heat tolerance. Twelve qualitative characters were recorded. The qualitative characters were analyzed as degree of similarity. DICE Similarity coefficient of qualitative data was 0.06. Broad variability in the genotypic, phenotypic variances and genetic advance was found for leaf length, leaf width and heat tolerance score. Of the electrolyte leakage analyses, it was found that flower length, ventral petal length width, lateral petal length and spur length positively support the high tolerance of Impatiens accession to heat stress. The darker color of the stem, anther, and bract is followed by a reduction in the dimension of flower width, lateral petal width, dorsal petal width and spur length but the increased leaf thicknesses. There was no direct correlation between the heat tolerance score and the leaf thickness. The largest data diversity explained by 3 factors with a total variance of 68.88 %.

Association of Obesity and Plantar Fasciitis in Patients With Plantar Heel Spurs

Background: Although its pathophysiology is not clear, the presence of a plantar heel spur has been considered a cause of heel pain in plantar fasciitis. This study investigated demographic and radiographic differences between a plantar fasciitis patient group with plantar heel spur and the age/sex-matched control group with plantar heel spur. Methods: Patients who visited the office under the diagnosis of plantar fasciitis and had a plantar heel spur were compared to an age/sex-matched control group who visited the office with other foot and ankle issues except for heel pain. All patients in both the control and case groups had radiographically proven presence of a plantar heel spur. Demographics and radiographic findings between the 2 groups were compared, and a multivariable logistic regression analysis was performed to identify independent risk factors that are associated with plantar fasciitis symptoms. Results: A total of 100 patients were included in the plantar fasciitis study group (PF+S) and age/sex-matched control group (C+S). BMI was higher in the study group than in the control group: 35.2 vs 30.9 ( P = .002). The size of the plantar heel spur was larger in the study group than in the control group: 5.9 vs 4.6 mm ( P = .017). A multivariable regression analysis identified that obesity (BMI &gt; 30, odds ratio [OR] = 2.675) and the size of plantar heel spur &gt;5.3 mm (OR = 2.642) were associated with PF+S. Conclusion: We found an association of both obesity and increased average plantar heel spur length on lateral radiographs in patients with painful plantar fasciitis compared to patients without plantar fasciitis but with plantar heel spurs. The presence of a plantar heel spur alone did not account for the symptoms of plantar fasciitis. Level of Evidence: Level III, comparative case study.

Effects of mechanical box pruning intensity on bud development, vegetative growth, and yield components on cv. Cabernet-Sauvignon in Mendoza, Argentina

Mechanised winter pruning is increasingly being used to reduce the high costs of manual pruning. Mechanised pruning is non-selective, and for its optimal application, the definition of pruning intensity is necessary to achieve the target yield and grape quality. Our objectives were to evaluate the effects of three intensities of mechanical box pruning compared to a manual pruning treatment on spur length, the number of retained buds, budburst, shoot growth, and development; yield components and berry composition, and vine balance. Treatments corresponded to three mechanical pruning intensities leading to different bud loads at the beginning of the experiment by pruning at different distances from the cordon (i.e., box size): MP1 (1 cm height × 7 cm width), MP2 (14 cm × 14 cm), and MP3 (21 cm × 21 cm). MP2 treatment was also compared to a traditional manual pruning treatment (SP) that was pruned to the same bud/plant in the first season. In the first season, MP2 retained the same bud/plant as SP, but in the second and third seasons, MP2 retained 88 % and 100 % more buds/plant than SP, respectively. Accordingly, MP2 and SP showed no difference in yields in the first season, but in the second season, MP2 showed a 39 % higher yield than SP. Regarding the intensity of mechanical pruning, after treatments were applied, the number of retained buds increased as box size increased. Treatments modified the length of spurs, budburst percentage and their pattern. In the first season, the yield on the highest box (MP3) was four times higher than the smallest box (MP1), but they showed similar yields in the second season. The intensity of mechanical box pruning, applied after two seasons, generated regulatory and compensation mechanisms (i.e., lower budburst and cluster weight), leading to similar yields independently of the pruning intensity. Our results show that (i) after two seasons, mechanical pruning was more productive than manual pruning, and (ii) mechanical pruning intensity had a marked influence on yield only during the first year of application, while some compensation mechanisms among yield components equilibrate yield afterwards.

Trait analysis in a population of the Greater Butterfly-orchid observed through a 16-year period.

A large English population of the temperate tuberous Greater Butterfly-orchid, Platanthera chlorantha, was monitored through a 16-year period. Each June the number of flowering plants was counted and 60 flowering plants were measured in situ for four morphological traits, selected for both ease of measurement and their contrasting contributions to the life history of the species. Trait data were tested annually in pairwise combinations for individual plants, before mean values throughout the study period were regressed and cross-correlated against each other and against local data for four meteorological parameters. Labellar spur length proved to be more constrained than either flower number or stem height, and rarely yielded statistically significant correlations with other traits, whereas the three remaining traits reliably showed modest but significant correlations. Mean values and coefficients of variation differed only modestly among years and showed few of any meaningful trends. Spring rainfall and insolation had no detectable effect on traits of plants flowering that June; instead, they impacted on trait expression during the following year, presumably as a result of differential resourcing of replacement tubers formed during the previous year. High spring rainfall in year t-1 increased leaf area and stem height in year t, whereas the widely fluctuating number of flowering plants was highest in years immediately following those characterised by relatively dry and/or sunny springs. The "decision" to flower is taken during the previous summer, though it may be modified through winter/spring abortion of above-ground organs. The proportion of the population electing to flower is the only measured parameter that impacts significantly on annual reproductive output, emphasising the under-rated difficulty of evolving through directional selection. Any attempt to predict the behaviour of plant species in response to climate change must integrate information on demography with that on life history, habitat preference and intimate symbioses.

Palynological and macroscopic characters evidence infer the evolutionary history and insight into pollination adaptation in Impatiens (Balsaminaceae)

AbstractThe genus Impatiens comprises more than 1000 species and displays enormous morphological diversity. As a taxon that is notoriously difficult to classify morphologically, the taxonomic significance of pollen morphology has been discussed in previous studies. However, there was only limited study on the evolution of palynological and macroscopic character in this genus before. In this paper, we observed pollen of 143 species of Impatiens, including all representatives of infrageneric groups and discussed their taxonomic value. Meanwhile, based on the reconstructed phylogenetic framework, we selected five pollen traits, and nine macroscopic traits including both vegetative and reproductive organs for evolutionary analysis. The character reconstruction showed that the morphology and number of aperture, granules in lumina, seed number of per capsule, number of sepals, lateral united petals connate, spur length, and phyllotaxy could be identified as unambiguous, while other characters were ambiguous in the last common ancestor of Impatiens. The results of comprehensively macroscopic characters and palynological evidence suggest that these traits experienced a complicated evolution, exhibit high levels of instability and variability and occur character multiple reversals in the evolutionary processes of Impatiens due to different selection pressures. In addition, we found that there is an evident mosaic evolution in this genus. Pollen and macroscopic character are conserved with a slower evolutionary rate in the I. subgen. Clavicarpa, however, these characters showed higher diversity with a rapid rate of evolution in the I. subgen. Impatiens. Furthermore, the relationship between floral morphology and pollinators was discussed.

Enlarged occipital spur and craniofacial morphology: a cephalometric analysis.

This cross-sectional study aimed to investigate the association between the occipital spur length and craniofacial morphology in individuals with occipital spur (OS). The study included cephalometric images from 451 individuals (196 females, 255 males, age range was 9-84years). The spur length and craniofacial characteristics were evaluated using cephalograms. Based on spur length, subjects were divided into two groups: the OS group (N = 209) and the enlarged occipital spur (EOS) group (N = 242). Descriptive statistics, Independent T-test, Mann-Whitney U test, chi-square test, Kruskal-Wallis test, and age- and sex-based stratified analyses were performed. The level of significance was set at p < 0.05. Males had significantly larger spur length than females. Spur length was shorter in individuals under 18 than the groups over 18. After adjusting for gender and age, ramus height, mandibular body length, effective length of maxilla, effective length of mandible, anterior cranial base length, posterior cranial base length, anterior facial height, posterior facial height, facial height index, and lower anterior facial height had statistically significant differences between OS group and EOS group. Males exhibit greater spur length than females. Patients under 18 had a shorter spur length than adults. Linear craniofacial measurements were found to be greater in subjects with EOS than the individuals with OS. The craniofacial growth and development of an individual might be associated with EOS. The causal relationship between EOS and craniofacial development requires further longitudinal studies.

Floral and genetic divergence across environmental gradients is moderated by inter-population gene flow in Platanthera dilatata (Orchidaceae)

Understanding how natural selection acts on intraspecific variation to bring about phenotypic divergence is critical to understanding processes of evolutionary diversification. The orchid family is well known for pollinator-mediated selection of floral phenotypes operating among species and along environmental or geographic gradients. Its effectiveness at small spatial scales is less understood, making the geographic scale at which intraspecific floral variation is examined important to evaluating causes of phenotypic divergence. In this study, we quantified phenotypic variation in the orchid Platanthera dilatata across 26 populations in coastal Southeast Alaska and compared this to edaphic and genetic variation at microsatellite loci. We sought to determine (1) if flower morphological variation is structured at smaller geographic scales, (2) the extent of genetic divergence in relation to phenotypic divergence, (3) the scale at which inter-population gene flow occurs, and (4) the relative importance of geographic distance and abiotic factors on population genetic structure. Two morphological groups were found to separate based on lip and spur length and are restricted to different habitats. Small-flowered forms occur in muskeg bogs, whereas large-flowered forms occur in fens and meadows, and rarely in sub-alpine habitat. Genetic analyses were concordant with the morphological clusters, except for four small-flowered populations that were genetically indistinguishable from large-flowered populations and considered to be introgressed. In fact, most populations exhibited some admixture, indicating incomplete reproductive isolation between the flower forms. Pollinators may partition phenotypes but also facilitate gene flow because short-tongued Noctuidae moths pollinate both phenotypes, but longer-tongued hawkmoths were only observed pollinating the large-flowered phenotype, which may strengthen phenotypic divergence. Nevertheless, pollinator movement between habitats could have lasting effects on neutral genetic variation. At this small spatial scale, population genetic structure is only associated with environmental distance, likely due to extensive seed and pollinator movement. While this study corroborates previous findings of cryptic genetic lineages and phenotypic divergence in P. dilatata, the small scale of examination provided greater understanding of the factors that may underlie divergence.