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1.
Front Cell Dev Biol ; 12: 1414601, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39105171

RESUMEN

Measuring mechanical forces of cell-cell interactions is important for studying morphogenesis in multicellular organisms. We previously reported an image-based statistical method for inferring effective mechanical potentials of pairwise cell-cell interactions by fitting cell tracking data with a theoretical model. However, whether this method is applicable to tissues with non-cellular components such as cavities remains elusive. Here we evaluated the applicability of the method to cavity-harboring tissues. Using synthetic data generated by simulations, we found that the effect of expanding cavities was added to the pregiven potentials used in the simulations, resulting in the inferred effective potentials having an additional repulsive component derived from the expanding cavities. Interestingly, simulations by using the effective potentials reproduced the cavity-harboring structures. Then, we applied our method to the mouse blastocysts, and found that the inferred effective potentials can reproduce the cavity-harboring structures. Pairwise potentials with additional repulsive components were also detected in two-dimensional cell sheets, by which curved sheets including tubes and cups were simulated. We conclude that our inference method is applicable to tissues harboring cavities and cell sheets, and the resultant effective potentials are useful to simulate the morphologies.

2.
Proc Natl Acad Sci U S A ; 121(25): e2403809121, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38861596

RESUMEN

The dorsal and anal fins can vary widely in position and length along the anterior-posterior axis in teleost fishes. However, the molecular mechanisms underlying the diversification of these fins remain unknown. Here, we used genetic approaches in zebrafish and medaka, in which the relative positions of the dorsal and anal fins are opposite, to demonstrate the crucial role of hox genes in the patterning of the teleost posterior body, including the dorsal and anal fins. By the CRISPR-Cas9-induced frameshift mutations and positional cloning of spontaneous dorsalfinless medaka, we show that various hox mutants exhibit the absence of dorsal or anal fins, or a stepwise posterior extension of these fins, with vertebral abnormalities. Our results indicate that multiple hox genes, primarily from hoxc-related clusters, encompass the regions responsible for the dorsal and anal fin formation along the anterior-posterior axis. These results further suggest that shifts in the anterior boundaries of hox expression which vary among fish species, lead to diversification in the position and size of the dorsal and anal fins, similar to how modulations in Hox expression can alter the number of anatomically distinct vertebrae in tetrapods. Furthermore, we show that hox genes responsible for dorsal fin formation are different between zebrafish and medaka. Our results suggest that a novel mechanism has occurred during teleost evolution, in which the gene network responsible for fin formation might have switched to the regulation downstream of other hox genes, leading to the remarkable diversity in the dorsal fin position.


Asunto(s)
Aletas de Animales , Genes Homeobox , Proteínas de Homeodominio , Oryzias , Pez Cebra , Animales , Oryzias/genética , Pez Cebra/genética , Genes Homeobox/genética , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Regulación del Desarrollo de la Expresión Génica , Tipificación del Cuerpo/genética , Proteínas de Peces/genética , Proteínas de Peces/metabolismo
3.
Heliyon ; 10(4): e25332, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38404900

RESUMEN

This study aimed to assess morphological diversity within Salacia kraussii, a fruit and medicinal wild plant species, based on morphological features and compared the fruit production among morphological types (morphotype) that naturally occur on the northern coast of KwaZulu-Natal. Following one species plant survey, a description of the qualitative morphological features revealed that S. kraussii individuals mainly differed in their leaf shapes, having elliptic, oblong, or obovate leaves. That led us to the identification of three morphotypes, namely Salacia kraussii 'elliptic', Salacia kraussii 'oblong' and Salacia kraussii 'obovate'. The analysis of variance (one-way ANOVA) of plant quantitative features indicated that plant height, stem diameter, branch number, leaf number and area, and fruit number were significantly different between plants from different sites (p-values < 0.05) and morphotypes (p-values < 0.01). Generally, S. kraussii grows in KwaZulu-Natal as a suffrutex with many stems and exhibits short plant height, small stem diameter, branches, and little foliage per stem. The average fruit number recorded per plant stem was likewise few. Plants growing in Sikhalasenkosi (site1) dominated in average plant height (35.58 cm), leaf number (45), number of branches (4), and number of fruits (5). Plants with elliptic leaves constantly dominated in average plant height (34.45 cm), foliage (36 leaves of 16.29 cm2 each), number of branches (4), and number of fruits (5). A few plants exhibited a strong vegetative vigor and produced more than 20 fruits. There was a highly positive correlation (CC = 0.8) between plant height and leaf number, branch number and leaf number, and branch number and fruit number. However, a negative correlation (CC = -0.1) was recorded between the leaf area and stem diameter. Overall, the study showed wide morphological diversity and fruit production within and between populations of S. kraussii, on the northern coast of KwaZulu-Natal.

4.
Ann Bot ; 133(5-6): 773-788, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38243607

RESUMEN

BACKGROUND AND AIMS: Quantifying spatial species richness is useful to describe biodiversity patterns across broad geographical areas, especially in large, poorly known plant groups. We explore patterns and predictors of species richness across Africa in one such group, the palaeotropical genus Grewia L. (Malvaceae). METHODS: Grewia species richness was quantified by extracting herbarium records from GBIF and Tropicos and creating geographical grids at varying spatial scales. We assessed predictors of species richness using spatial regression models with 30 environmental variables. We explored species co-occurrence in Madagascar at finer resolutions using Schoener's index and compared species range sizes and International Union for Conservation of Nature status among ecoregions. Lastly, we derived a trait matrix for a subset of species found in Madagascar to characterize morphological diversity across space. KEY RESULTS: Grewia species occur in 50 countries in Africa, with the highest number of species in Madagascar (93, with 80 species endemic). Species richness is highest in Madagascar, with ≤23 Grewia species in a grid cell, followed by coastal Tanzania/Kenya (≤13 species) and northern South Africa and central Angola (11 species each). Across Africa, higher species richness was predicted by variables related to aridity. In Madagascar, a greater range in environmental variables best predicted species richness, consistent with geographical grid cells of highest species richness occurring near biome/ecoregion transitions. In Madagascar, we also observe increasing dissimilarity in species composition with increasing geographical distance. CONCLUSIONS: The spatial patterns and underlying environmental predictors that we uncover in Grewia represent an important step in our understanding of plant distribution and diversity patterns across Africa. Madagascar boasts nearly twice the Grewia species richness of the second most species-rich country in Africa, which might be explained by complex topography and environmental conditions across small spatial scales.


Asunto(s)
Biodiversidad , Madagascar , África , Geografía
5.
Cell Rep ; 43(1): 113635, 2024 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-38160393

RESUMEN

Spinal neural circuits that execute movement are composed of cardinal classes of neurons that emerged from distinct progenitor lineages. Each cardinal class contains multiple neuronal subtypes characterized by distinct molecular, anatomical, and physiological characteristics. Through a focus on the excitatory V3 interneuron class, here we demonstrate that interneuron subtype diversity is delineated through a combination of neurogenesis timing and final laminar settling position. We have revealed that early-born and late-born embryonic V3 temporal classes further diversify into subclasses with spatially and molecularly discrete identities. While neurogenesis timing accounts for V3 morphological diversification, laminar settling position accounts for electrophysiological profiles distinguishing V3 subtypes within the same temporal classes. Furthermore, V3 interneuron subtypes display independent behavioral recruitment patterns demonstrating a functional modularity underlying V3 interneuron diversity. These studies provide a framework for how early embryonic temporal and spatial mechanisms combine to delineate spinal interneuron classes into molecularly, anatomically, and functionally relevant subtypes in adults.


Asunto(s)
Interneuronas , Médula Espinal , Interneuronas/fisiología , Movimiento , Neurogénesis/fisiología
6.
Evolution ; 78(3): 480-496, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38150399

RESUMEN

Greater diversity in functional morphology should be associated with the evolution of greater ontogenetic diversity, an expectation difficult to test in most long-lived wild organisms. In the cells derived from the wood meristem (vascular cambium), plants provide extraordinary systems for reconstructing ontogenies in often long-lived organisms. The vascular cambium produces files of cells from the stem center to the periphery, with each cambial derivative "deciding" which of four cell types it differentiates into. Wood cell files remain in place, allowing tracing of the ontogenetic "decisions" taken throughout the life of a stem. We compared cell files from the Pedilanthus clade (genus Euphorbia), which span a range of growth forms from small trees and shrubs of tropical habitats to desert succulents. Using language theory, we represented wood cell types as "letters" and combinations of cell types in cell files as "words," allowing us to measure the diversity of decisions based on word frequency matrices. We also used information content metrics to compare levels of predictability in "decision-making." Our analyses identified a wider array of developmental decisions in woody trees as compared to succulent shrubs, illustrating ways that woody plants provide unparalleled systems for studying the evolution of ontogeny in long-lived, non-model species.


Asunto(s)
Plantas , Madera , Cámbium/anatomía & histología , Árboles/anatomía & histología , Ecosistema
7.
Plants (Basel) ; 12(21)2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-37960137

RESUMEN

Litsea cubeba (Lour.) Pers. is an important woody spice tree in southern China, and its fruit is a rich source of valuable essential oil. We surveyed and sampled L. cubeba germplasm resources from 36 provenances in nine Chinese provinces, and detected rich phenotypic diversity. The survey results showed that plants of SC-KJ, SC-HJ, and SC-LS provenance presented higher leaf area (LA); YN-SM and YN-XC plants had larger thousand-grain fresh weight (TFW); and HN-DX plants had the highest essential oil content (EOC). To explain the large differences in the phenotypes of L. cubeba among different habitats, we used Pearson's correlation analysis, multiple stepwise regression path analysis, and redundancy analysis to evaluate the phenotypic diversity of L. cubeba. It was found that compared to other traits, leaf and fruit traits had more significant geographical distributions, and that leaf phenotypes were correlated to fruit phenotypes. The results showed that elevation, latitude, longitude, total soil porosity (SP), soil bulk density (SBD), and average annual rainfall (AAR, mm) contributed significantly to the phenotypic diversity of L. cubeba. Geographical factors explained a higher percentage of variation in phenotypic diversity than did soil factors and climate factors. Plants of SC-KJ and HN-DX provenances could be important resources for domestication and breeding to develop new high-yielding varieties of this woody aromatic plant. This study describes significant phenotypic differences in L. cubeba related to adaptation to different environments, and provides a theoretical basis for the development of a breeding strategy and for optimizing L. cubeba cultivation.

8.
MycoKeys ; 100: 49-67, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38025584

RESUMEN

More specimens of Hydnotrya have been collected from southwestern China in recent years. Morphological and molecular analyses showed that they belonged to three species of Hydnotrya, of which two are new to science, H.oblongispora and H.zayuensis. The third one was H.laojunshanensis, previously reported in 2013. The new species are described, and their relationship to other species of Hydnotrya is discussed. H.laojunshanensis is re-described in more detail. The main morphological characters of 17 species of Hydnotrya are compared and a key to them is provided as well.

9.
Clin Case Rep ; 11(11): e8149, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38028045

RESUMEN

Key Clinical Message: This case report highlights the importance of recognizing and accurately diagnosing ganglioneuroblastoma, an uncommon variant of neuroblastic tumors in children. Ganglioneuroblastomas have diverse clinical and morphological presentations, and histopathological examination is paramount in guiding treatment decisions, especially in cases with ambiguous symptoms. Early detection is crucial, as the prognosis varies significantly based on the subtype and the presence of metastatic disease. Clinicians should maintain a high index of suspicion and utilize radiological examinations to promptly identify and treat these tumors. Abstract: Children are frequently affected by neuroblastic tumors, which grow from the sympathoadrenal lineage of the neural crest during its development. However, intermixed ganglioneuroblastomas are far less common within the same tumor spectrum, the diagnosis of which could become challenging amidst an unusual presentation. In our case report, we present a 4-year-old boy who had complaints of fever and difficulty in walking, with a supra-renal mass on ultrasound, which was diagnosed as ganglioneuroblastoma-intermixed type on histopathological examination. This report aims to contribute to the understanding of the diverse clinical and morphological spectrum of ganglioneuroblastomas and the importance of multidisciplinary collaboration and histopathological examination to enhance decision-making in such ambiguous scenarios.

10.
Front Plant Sci ; 14: 1176517, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37731989

RESUMEN

Faba bean ascochyta blight, caused by Ascochyta fabae Speg. (teleomorph: Didymella fabae Punith.), is one of the most devastating diseases of the crop. It can cause yield losses that reach 95% in conducive weather conditions. Surveys were carried out in five regions of Tunisia: Beja, Bizerte, Jendouba, Kef and Tunis-Cap Bon. A total of 513 fungal isolates were collected from 2011 to 2013. A molecular characterization was conducted to identify the mating type of each individual using a mating type specific PCR. Results revealed that the two mating types MAT1-2 and MAT1-1 coexisted in all surveyed regions. An imbalance in favor of MAT1-2 was observed particularly in Bizerte and Jendouba regions (sex ratio was 18:85 and 32:80, respectively). Moreover, morphological and pathogenic characterization of 122 isolates among the collection revealed a significant variability in conidia type (one celled or two celled conidia) frequency, in conidia mean size and in aggressiveness toward Badii faba bean cultivar (incubation period, IP; percentage necrotic leaf area, S; and area under disease progression curve, AUDPC). A principal component analysis (PCA) performed on morphologically studied parameters (frequency of conidia cell number and conidia mean size) identified three groups of isolates based on morphological traits: one celled (1C) and two celled (2C) conidia rates, one celled and two celled conidia length and width (1L, 1W, 2L and 2W, respectively). A second PCA using aggressiveness parameters (IP: Incubation period, S1, S4 and S9: percentage of necrotic leaf area respectively 5, 20 and 45 days after inoculation) identified three distinct pathogenic groups: poorly pathogenic AG1, moderately pathogenic AG2 and highly pathogenic AG3. Morphological and pathogenic groups and mating type data were used to conduct a multiple factorial correspondence analysis (MFCA) which revealed a correlation between the variables studied. Five groups were identified, each associated with a morphological and pathogenic trait and mating type. The most pathogenic group belonged to MAT1-2 suggesting that in locations where MAT1-2 is prevalent the epidemic risk is more important.

11.
PeerJ ; 11: e15767, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37576509

RESUMEN

Background: Understanding morpho-genetic diversity and differentiation of species with relatively large distributions is crucial for the conservation and sustainable management of their genetic resources. The present study focused on Annona senegalensis Pers., an important multipurpose wild plant, distributed exclusively in natural ecosystems but facing several threats. The study assessed the genetic and morphological diversity, structure, and differentiation of the species in populations from Western (Benin) and Southern (Mozambique) Africa. The material was evaluated to ascertain the environmental (climatic) determinants of the variation within this species. Methods: Four sub-populations comprised of 154 individuals were phenotyped based on nineteen plant, fruit, and leaf morphological traits and further genotyped using ten polymorphic nuclear microsatellite (nSSR) markers. Results: The results indicated strong differences in plant, fruit, and leaf morphological traits between Western and Southern populations. Furthermore, the studied populations were characterized by high genetic diversity, with an average genetic diversity index of 1.02. Western populations showed higher heterozygosity values (0.61-0.71) than Southern populations (0.41-0.49). Western and Southern populations were clearly differentiated into two different genetic groups, with further genetic subdivisions reflecting four sub-populations. Genetic variation between regions (populations) was higher (69.1%) than among (21.3%) and within (9.6%) sub-populations. Four distinct morphological clusters were obtained, which were strongly associated with the four genetic groups representing each sub-population. Climate, mainly precipitation and temperature indexes, explained the relatively higher variation found in morphological traits from Western (40.47%) in relation to Southern (27.98%) populations. Our study suggests that both environmental and genetic dynamics play an important role in the development of morphological variation in A. senegalensis.


Asunto(s)
Annona , Variación Genética , Humanos , Variación Genética/genética , Annona/genética , Mozambique , Benin , Ecosistema
12.
J Hum Evol ; 182: 103411, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37531709

RESUMEN

Excavations in Hualongdong (HLD), East China, have yielded abundant hominin fossils dated to 300 ka. There is a nearly complete mandible that fits well with a partial cranium, and together they compose the skull labeled as HLD 6. Thus far, detailed morphological description and comparisons of the mandible have not been conducted. Here we present a comprehensive morphological, metric, and geometric morphometric assessment of this mandible and compare it with both adult and immature specimens of Pleistocene hominins and recent modern humans. Results indicate that the HLD 6 mandible exhibits a mosaic morphological pattern characterized by a robust corpus and relatively gracile symphysis and ramus. The moderately developed mental trigone and a clear anterior mandibular incurvation of the HLD 6 mandible are reminiscent of Late Pleistocene hominin and recent modern human morphology. However, the weak expression of all these features indicates that this mandible does not possess a true chin. Moreover, a suite of archaic features that resemble those of Middle Pleistocene hominins includes pronounced alveolar planum, superior transverse torus, thick corpus, a pronounced endocondyloid crest, and a well-developed medial pterygoid tubercle. The geometric morphometric analysis further confirms the mosaic pattern of the HLD 6 mandible. The combination of both archaic and modern human features identified in the HLD 6 mandible is unexpected, given its late Middle Pleistocene age and differs from approximately contemporaneous Homo members such as Xujiayao, Penghu, and Xiahe. This mosaic pattern has never been recorded in late Middle Pleistocene hominin fossil assemblages in East Asia. The HLD 6 mandible provides further support for the high morphological diversity during late Middle Pleistocene hominin evolution. With these findings, it is possible that modern human morphologies are present as early as 300 ka and earlier than the emergence of modern humans in East Asia.


Asunto(s)
Hominidae , Diente , Animales , Humanos , Hominidae/anatomía & histología , Diente/anatomía & histología , China , Mandíbula/anatomía & histología , Cráneo/anatomía & histología , Fósiles
13.
MycoKeys ; 98: 153-165, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37396021

RESUMEN

Glypholeciaqinghaiensis An C. Yin, Q. Y. Zhong & Li S. Wang is described as new to science. It is characterized by its squamulose thallus, compound apothecia, ellipsoid ascospores, and the presence of rhizines on the lower surface of the thallus. A phylogenetic tree of Glypholecia species was constructed based on nrITS and mtSSU sequences. Two species G.qinghaiensis and G.scabra are confirmed in China.

14.
Hydrobiologia ; 850(10-11): 2257-2273, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37325486

RESUMEN

Variation in fin shape is one of the most prominent features of morphological diversity among fish. Regulation of fin growth has mainly been studied in zebrafish, and it is not clear whether the molecular mechanisms underlying shape variation are equally diverse or rather conserved across species. In the present study, expression levels of 37 candidate genes were tested for association with fin shape in the cichlid fish Lamprologus tigripictilis. The tested genes included members of a fin shape-associated gene regulatory network identified in a previous study and novel candidates selected within this study. Using both intact and regenerating fin tissue, we tested for expression differences between the elongated and the short regions of the spade-shaped caudal fin and identified 20 genes and transcription factors (including angptl5, cd63, csrp1a, cx43, esco2, gbf1, and rbpj), whose expression patterns were consistent with a role in fin growth. Collated with available gene expression data of two other cichlid species, our study not only highlights several genes that were correlated with fin growth in all three species (e.g., angptl5, cd63, cx43, and mmp9), but also reveals species-specific gene expression and correlation patterns, which indicate considerable divergence in the regulatory mechanisms of fin growth across cichlids. Supplementary Information: The online version contains supplementary material available at 10.1007/s10750-022-05068-4.

15.
Evolution ; 77(5): 1216-1225, 2023 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-36821408

RESUMEN

Cyanobacteria morphology has apparently remained almost unchanged for billions of years, exhibiting remarkable evolutionary stasis. Cyanobacteria appear to have reached their maximum morphological complexity in terms of size, modes of multicellularity, and cellular types by ~2 Ga. This contrasts with the increased complexity observed in other multicellular lineages, such as plants. Using experimental evolution, we show that morphological diversity can rapidly evolve in a species of filamentous cyanobacteria. Since size has such significance with regard to organismal complexity, we subjected the heterocyst-forming cyanobacterium Trichornus variabilis (syn. Anabaena variabilis) to selection for larger size. We observed increases in size of more than 30-fold, relative to the ancestral population, after 45 cycles of selection. Two distinguishable nascent morphological elaborations were identified in all the selected populations: Tangle (long, tangled filaments) and Cluster (clusters of short filaments) morphology. Growth from single cells indicates heritability of the evolved Tangle and Cluster morphological phenotypes. Cyanobacteria evolutionary conservatism is ascribed to developmental constraints, slow evolution rates, or ecological flexibility. These results open opportunities to study possibilities and constraints for the evolution of higher integrated biological levels of organization within this lineage.


Asunto(s)
Anabaena variabilis , Anabaena , Anabaena/genética
16.
Curr Biol ; 32(17): 3830-3837.e3, 2022 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-35868322

RESUMEN

Biodiversity is facing a global extinction crisis that will reduce ecological trait diversity, evolutionary history, and ultimately ecosystem functioning and services.1-4 A key challenge is understanding how species losses will impact morphological and phylogenetic diversity at global scales.5,6 Here, we test whether the loss of species threatened with extinction according to the International Union for Conservation of Nature (IUCN) leads to morphological and phylogenetic homogenization7,8 across both the whole avian class and within each biome and ecoregion globally. We use a comprehensive set of continuous morphological traits extracted from museum collections of 8,455 bird species, including geometric morphometric beak shape data,9 and sequentially remove species from those at most to least threat of extinction. We find evidence of morphological, but not phylogenetic, homogenization across the avian class, with species becoming more alike in terms of their morphology. We find that most biome and ecoregions are expected to lose morphological diversity at a greater rate than predicted by species loss alone, with the most imperiled regions found in East Asia and the Himalayan uplands and foothills. Only a small proportion of assemblages are threatened with phylogenetic homogenization, in particular parts of Indochina. Species extinctions will lead to a major loss of avian ecological strategies, but not a comparable loss of phylogenetic diversity. As the decline of species with unique traits and their replacement with more widespread generalist species continues, the protection of assemblages at most risk of morphological and phylogenetic homogenization should be a key conservation priority.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Animales , Biodiversidad , Aves/genética , Extinción Biológica , Filogenia
17.
Int J Mol Sci ; 23(3)2022 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-35163686

RESUMEN

Three Dysteria species, D. crassipes Claparède & Lachmann, 1859; D. brasiliensis Faria et al., 1922; and D. paracrassipes n. sp., were collected from subtropical coastal waters of the East China Sea, near Ningbo, China. The three species were studied based on their living morphology, infraciliature, and molecular data. The new species D. paracrassipes n. sp. is very similar to D. crassipes in most morphological features except the preoral kinety, which is double-rowed in the new species (vs. single-rowed in D. crassipes). The difference in the small ribosomal subunit sequences (SSU rDNA) between these two species is 56 bases, supporting the establishment of the new species. The Ningbo population of D. crassipes is highly similar in morphology to other known populations. Nevertheless, the SSU rDNA sequences of these populations are very different, indicating high genetic diversity and potentially cryptic species. Dysteria brasiliensis is cosmopolitan with many described populations worldwide and four deposited SSU rDNA sequences. The present work supplies morphological and molecular information from five subtropical populations of D. brasiliensis that bear identical molecular sequences but show significant morphological differences. The findings of this study provide an opportunity to improve understanding of the morphological and genetic diversity of ciliates.


Asunto(s)
Cilióforos/clasificación , Cilióforos/genética , Filogenia , Secuencia de Bases , China , ADN Ribosómico/genética , Geografía , Funciones de Verosimilitud , ARN Ribosómico/genética , Subunidades Ribosómicas Pequeñas/genética , Homología de Secuencia de Ácido Nucleico , Especificidad de la Especie
18.
Ecol Lett ; 25(3): 598-610, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35199925

RESUMEN

Understanding the biogeographical patterns, and evolutionary and environmental drivers, underpinning morphological diversity are key for determining its origins and conservation. Using a comprehensive set of continuous morphological traits extracted from museum collections of 8353 bird species, including geometric morphometric beak shape data, we find that avian morphological diversity is unevenly distributed globally, even after controlling for species richness, with exceptionally dense packing of species in hyper-diverse tropical hotspots. At the regional level, these areas also have high morphological variance, with species exhibiting high phenotypic diversity. Evolutionary history likely plays a key role in shaping these patterns, with evolutionarily old species contributing to niche expansion, and young species contributing to niche packing. Taken together, these results imply that the tropics are both 'cradles' and 'museums' of phenotypic diversity.


Asunto(s)
Biodiversidad , Aves , Animales , Pico , Evolución Biológica , Fenotipo
19.
BMC Genom Data ; 23(1): 3, 2022 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-34991442

RESUMEN

BACKGROUND: The present study aimed at characterizing the Djallonké Sheep (DS), the only local sheep breed raised in Guinea-Bissau. A total of 200 animals were sampled from four regions (Bafatá, Gabú, Oio and Cacheu) and described using 7 visual criteria and 8 measurements. These parameters have been studied by principal components analysis. The genetic diversity and population structure of 92 unrelated animals were studied using 12 microsatellite markers. RESULTS: The values of quantitative characters in the Bafatá region were significantly higher than those obtained in the other three regions. A phenotypic diversity of the DS population was observed and three genetic types distinguished: animals with "large traits" in the region of Bafatá, animals with "intermediate traits" in the regions of Gabú and Oio and animals with "small traits" in the Cacheu region. The hair coat colors are dominated by the white color, the shape of the facial head profile is mainly convex and the ears "erected horizontally". Most of the morphobiometric characteristics were significantly influenced by the "region" and "sex of animals". The average Polymorphism Information Content (PIC) of 0.65 ± 0.11 supports the use of markers in genetic characterization. Gabú subpopulation had the highest genetic diversity measures (He = 0.716 ± 0.089) while Cacheu DS subpopulation presented the smallest (He = 0.651 ± 0.157). Only Gabú and Bafatá subpopulations presented significant heterozygote deficiency across all loci indicating possible significant inbreeding. Mean values for FIT, FST, FIS and GST statistics across all loci were 0.09, 0.029, 0.063 and 0.043 respectively. The overall genetic differentiation observed between the four DS subpopulations studied was low. Bafatá and Gabú are the most closely related subpopulations (DS = 0.04, genetic identity = 0.96) while Bafatá and Cacheu were the most genetically distant subpopulations (DS = 0.14, genetic identity = 0.87). Using Bayesian approach, the number of K groups that best fit the data is detected between 2 and 3, which is consistent with the morphological analysis and the factorial analysis of correspondence. CONCLUSIONS: The molecular results on DS population of Guinea-Bissau confirmed the ones obtained with morphological analysis. The three genetic types observed phenotypically might be due to a combination of the agro-ecological differences and the management of breeding rather than genetic factors.


Asunto(s)
Endogamia , Repeticiones de Microsatélite , Animales , Teorema de Bayes , ADN/química , Guinea Bissau/epidemiología , Masculino , Repeticiones de Microsatélite/genética , Ovinos/genética
20.
Zookeys ; 1129: 85-107, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36761843

RESUMEN

After extensive sampling of specimens from species found in China, we examined the intraspecific morphological variation of several characters used for species delimitation in two closely related cricket genera, Gymnogryllus Saussure, 1877 and Phonarellus Gorochov, 1983. We found that the characters (male genitalia in Gymnogryllusodonopetalus Xie & Zheng, 2003 and Phonarellusritsemae (Saussure, 1877), and coloration of the hind leg in Phonarellusminor (Chopard, 1959)) exhibit considerable amounts of variation within species, and are thus not reliable characters for species differentiation. Therefore, we revised the taxonomy of these two genera. Five synonyms are proposed: G.yunnanensis (= G.odonopetalus) syn. nov., G.striatus (= G.odonopetalus) syn. nov., G.longus (= G.odonopetalus) syn. nov., G.tumidulus (= G.odonopetalus) syn. nov., and P.flavipes (= P.minor) syn. nov. All species mentioned above are described and illustrated. Keys and a distribution map are provided.

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