Across-nation differences in the mean values for complex traits are common, but the reasons for these differences are unknown. Here we find that many independent loci contribute to population genetic ...differences in height and body mass index (BMI) in 9,416 individuals across 14 European countries. Using discovery data on over 250,000 individuals and unbiased effect size estimates from 17,500 sibling pairs, we estimate that 24% (95% credible interval (CI) = 9%, 41%) and 8% (95% CI = 4%, 16%) of the captured additive genetic variance for height and BMI, respectively, reflect population genetic differences. Population genetic divergence differed significantly from that in a null model (height, P < 3.94 × 10(-8); BMI, P < 5.95 × 10(-4)), and we find an among-population genetic correlation for tall and slender individuals (r = -0.80, 95% CI = -0.95, -0.60), consistent with correlated selection for both phenotypes. Observed differences in height among populations reflected the predicted genetic means (r = 0.51; P < 0.001), but environmental differences across Europe masked genetic differentiation for BMI (P < 0.58).
Grain morphology in wheat (Triticum aestivum) has been selected and manipulated even in very early agrarian societies and remains a major breeding target. We undertook a large-scale quantitative ...analysis to determine the genetic basis of the phenotypic diversity in wheat grain morphology. A high-throughput method was used to capture grain size and shape variation in multiple mapping populations, elite varieties, and a broad collection of ancestral wheat species. This analysis reveals that grain size and shape are largely independent traits in both primitive wheat and in modern varieties. This phenotypic structure was retained across the mapping populations studied, suggesting that these traits are under the control of a limited number of discrete genetic components. We identified the underlying genes as quantitative trait loci that are distinct for grain size and shape and are largely shared between the different mapping populations. Moreover, our results show a significant reduction of phenotypic variation in grain shape in the modern germplasm pool compared with the ancestral wheat species, probably as a result of a relatively recent bottleneck. Therefore, this study provides the genetic underpinnings of an emerging phenotypic model where wheat domestication has transformed a long thin primitive grain to a wider and shorter modern grain.
•In vegetatively propagated crops, the loss of sexual reproduction capacity has been recognized as a domestication syndrome.•Results of pairwise PERMANOVA comparisons showed significant divergence ...between wild and domesticated enset in terms of their fruit and seed morphological characters.•Fruit weight, fruit length, fruit circumference, and number of seeds per fruit were the traits that differed most between cultivated and wild enset; significantly greater in the wild population.•Our results point to the possibility of complex evolutionary dynamics of both cultivated and wild forms.
Enset is a single-stemmed plant; i.e., non-suckering naturally both in wild and cultivated states. There are great differences in their life cycles between the wild and cultivated populations of enset. Wild enset reproduce naturally via seeds. As cultivated enset is usually harvested before or shortly after flowering, the development of flowers and fruits is rarely encountered in cultivation. As a result, cultivated enset is propagated vegetatively, with adventitious buds sprouting from the corm after the removal of the apical meristem. In vegetatively propagated crops, the loss of sexual reproduction capacity has been recognized as a domestication syndrome. The present study was performed to determine the pattern of fruit and seed variation between and within wild and cultivated populations, by measuring morphological differences in fruit and seed traits (number of hands per bunch, number of fruit per mid-hand, mean fruit weight, fruit length, fruit circumference, seed number per fruit, seed weight and seed diameter) in wild and cultivated plants. Results of pairwise PERMANOVA comparisons showed significant difference between wild and domesticated enset in terms of their fruit and seed morphological characters. Among the traits studied, average fruit weight, fruit length, fruit circumference, and number of seeds per fruit were the traits that differed most between cultivated and wild. These characters were significantly greater in the wild population than in cultivated. We suggest that these traits could define the domestication syndrome of this plant. Despite significant divergences between wild and cultivated ensets, some cultivated accessions, were certainly domesticated landrace are placed together with wild accessions in PCA biplot. Our results point to the possibility of complex evolutionary dynamics of both cultivated and wild forms, and gave an insight that there is huge potential to improve this crop through hybridization and clonal selection methods. Furthermore, the present results provide useful indications on how to act for more rational planning in reproductive material management and genetic resource conservation strategies.
Evolutionary mechanisms modulating the mammalian skull development Kyomen, Stella; Murillo-Rincón, Andrea P; Kaucká, Markéta
Philosophical transactions of the Royal Society of London. Series B. Biological sciences,
07/2023, Volume:
378, Issue:
1880
Journal Article
Peer reviewed
Open access
Mammals possess impressive craniofacial variation that mirrors their adaptation to diverse ecological niches, feeding behaviour, physiology and overall lifestyle. The spectrum of craniofacial ...geometries is established mainly during embryonic development. The formation of the head represents a sequence of events regulated on genomic, molecular, cellular and tissue level, with each step taking place under tight spatio-temporal control. Even minor variations in timing, position or concentration of the molecular drivers and the resulting events can affect the final shape, size and position of the skeletal elements and the geometry of the head. Our knowledge of craniofacial development increased substantially in the last decades, mainly due to research using conventional vertebrate model organisms. However, how developmental differences in head formation arise specifically within mammals remains largely unexplored. This review highlights three evolutionary mechanisms acknowledged to modify ontogenesis: heterochrony, heterotopy and heterometry. We present recent research that links changes in developmental timing, spatial organization or gene expression levels to the acquisition of species-specific skull morphologies. We highlight how these evolutionary modifications occur on the level of the genes, molecules and cellular processes, and alter conserved developmental programmes to generate a broad spectrum of skull shapes characteristic of the class Mammalia. This article is part of the theme issue 'The mammalian skull: development, structure and function'.
•A total of 33 traits were studied of 132 accessions.•Agglomeration hierarchical clustering (AHC) can distinguish all the 132 accessions into 3 major clusters.•This study helped for genetic ...relationships among guava accessions.•It can be used for other open pollinated fruit plant germplasm management and breeding strategies as well.
Cultivated guava (Psidium guajava L.) is an important commercial fruit crop. One hundred and thirty two accessions were collected from 12 regions in Pakistan for study of genetic diversity. A total of 33 traits (18 qualitative and 15 quantitative) enabled an assessment of the genetic variability and structure of this guava germplasm. The measured traits of fruit acidity, fruit diameter, seed weight, non-reducing sugars, thickness of outer flesh, number of seeds, fruit sweetness, longitudinal grooves, leaf twisting, fruit skin color, fruit shape at the stalk, longitudinal ridges, and flesh color were found highly variable. Many of these traits are of significant economic importance and could be used as breeding targets to increase fruit yield and fruit quality. There were strong positive correlations detected among the 15 quantitative traits related to fruit yield and fruit quality. These included fruit length and diameter, fruit weight and diameter, length and width of the leaf blade, number of seeds and seed weight, fruit weight and diameter of the fruit cavity, and seed weight and fruit weight. On the other hand, there were some negative correlations among the 18 qualitative traits studied. The 2D PCA plot successfully grouped the samples according to their phenotypic resemblance and morphological characteristics. The morphological dendrogram generated from agglomeration hierarchical clustering (AHC) grouped the 132 accessions into 3 major clusters.
The polychaete Family Cirratulidae is one of the most abundant and diverse groups of Annelida, although it remains poorly known worldwide.
Dodecaceria
Ørsted, 1843 is one of the least described ...genera of Cirratulidae. The present report is the first taxonomic study of the genus
Dodecaceria
for the Brazilian coast. Cirratulidae were collected at Rocas Atoll, the first Brazilian marine protected area and the only atoll in the South Atlantic Ocean. We described one new species,
Dodecaceria zelinhae
n. sp., and a new record of
D
.
dibranchiata
Blake & Dean, 2019, previously only known from Panama. The new species is distinguished from other
Dodecaceria
species by having lateral tentacles, a smooth peristomium, 3–5 pairs of branchiae, hooks from chaetiger 11 in notopodia and 9 in neuropodia.
Dodecaceria dibranchiata
, a Caribbean species, is here recorded for the first time in the South Atlantic Ocean.
•In the present study, phenotypic divergence among 65 individuals of three species belonging to Ziziphus genus was evaluated.•The clear differences were detected among the studied individuals for all ...of the noted characteristics.•Fruit weight ranged 1.10–3.08g for Z. spina-christi, while it was varied 0.98–2.10g for Z. nummularia and 0.96–3.14 for Z. oxyphylla.•Simple correlation analysis showed the existence of high significant positive correlations between leaf, and fruit characters.•The principal component and cluster analyses showed high phenotypic diversity among and within the studied species.
Ber (Ziziphus ssp.), a tropical and subtropical fruit, is native to the northern hemisphere. Little information is available about the phenotypic diversity of this fruit crop. In the present study, phenotypic divergence among 65 individuals of three species belonging to Ziziphus genus including Z. nummularia, Z. spina-christi and Z. oxyphylla was evaluated based on leaf and fruit characteristics. The clear differences were detected among the studied individuals for all of the noted characteristics. Leaf length ranged 1.89–3.70cm for Z. spina-christi, 1.64–3.59cm for Z. nummularia and 2.31–4.07cm for Z. oxyphylla. Fruit weight ranged 1.10–3.08g for Z. spina-christi, while it was varied 0.98–2.10g for Z. nummularia and 0.96–3.14g for Z. oxyphylla. The highest TSS for Z. spina-christi and Z. oxyphylla was 25%, while it was 28% for Z. nummularia. Seed weight ranged 0.32–1.17g for Z. spina-christi, 0.29–0.88g for Z. nummularia and 0.22–0.90g for Z. oxyphylla. Simple correlation analysis showed the existence of high significant positive correlations between leaf, and fruit characters. The principal component and cluster analyses showed high phenotypic diversity among and within the studied species, indicating that the measured traits were useful for characterization of Ziziphus genus. Finally, the present findings demonstrated that some of the studied individuals are to be promising for utilization in the breeding programs.
Vertebrates have some of the most complex and diverse features in animals, from varied craniofacial morphologies to colorful pigmentation patterns and elaborate social behaviors. All of these traits ...have their developmental origins in a multipotent embryonic lineage of neural crest cells. This “fourth germ layer” is a vertebrate innovation and the source of a wide range of adult cell types. While others have discussed the role of neural crest cells in human disease and animal domestication, less is known about their role in contributing to adaptive changes in wild populations. Here, we review how variation in the development of neural crest cells and their derivatives generates considerable phenotypic diversity in nature. We focus on the broad span of traits under natural and sexual selection whose variation may originate in the neural crest, with emphasis on behavioral factors such as intraspecies communication that are often overlooked. In all, we encourage the integration of evolutionary ecology with developmental biology and molecular genetics to gain a more complete understanding of the role of this single cell type in trait covariation, evolutionary trajectories, and vertebrate diversity.
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•Neural crest cells are unique to vertebrates and give rise to diverse cell types.•Neural crest changes produce variation in facial bones, pigmentation, and behavior.•Natural and sexual selection drive microevolution in neural crest derived traits.•A trait-based approach highlights how many adaptations originate in neural crest.•The role of neural crest in behavioral microevolution requires further exploration.
Medicago minima (L.) Bartal. has received little agricultural development to date, while having potentially useful traits compared to other “medics”, e.g., annual species of section Spirocarpos. ...However, the range of variation in M. minima requires further studies. This research assessed the diversity of the pod morphological traits of 13 populations in the southwest, west, northwest, and north of Iran. In addition, variation in nuclear ribosomal Internal Transcribed Spacer (nrITS, ITS 1+5.8s+ITS 2) was evaluated. No geographical patterns of variation in the pod traits were found. The molecular phylogenetic assessments of 7 populations indicated low variability, thus being grouped into a well-supported monophyletic clade (99% Bootstrap support/1.00 Posterior Probability (PP)). Nevertheless, the pod morphological traits exhibited significant variations, most notably in Glandular Hairs (GH), with a coefficient variation of 58%. For breeding and possibly conservation purposes, the following populations demonstrated potentially useful characteristics: (1) Baghcheh population with the highest number of seeds per pod (4.6) and angle of spine insertion (2.87◦); (2) Khoramabad population with a higher number of spines on the middle coil (65.27); and (3) Sarvabad population with the greatest fruit length (3.71 mm), fruit diameter (4.17 mm), Seed Length Trait (SLT) (2.37 mm), and Seed Width Trait (SWT) (1.35 mm). In qualitative traits, Khoramabad, Baghcheh, Marivan, and Paveh populations had higher scores, particularly for glandular pubescence and Simple Hairs (SH) on their pods. Results of the correlation analysis were often null or negative; however, altitude indicated a positive relationship with glandular pubescence and SH. No obvious correlations were found between pod morphology and ITS variation and geographical proximity.
We used sequences of the mitochondrial ND2 gene, the nuclear TGFB-2 intron-5, and differences in plumage pattern to assay geographic variation in the Red-bellied Woodpecker (Melanerpes carolinus). ...Ten population samples from throughout its range indicated that ~23% of the mitochondrial genetic variation was distributed among populations, largely due to the occurrence of a clade of haplotypes restricted to the Florida peninsula with a local frequency of 82%. In a hierarchical analysis, 37% of the mtDNA genetic variance was distributed between the Florida peninsula and elsewhere. A strong signal of population growth was detected in the non-peninsular portion of the range. Otherwise, geographic variation in haplotype frequencies was minor, with no evidence of isolation-by-distance. Nuclear intron data showed little variation among populations (F.sub.st = 0.007). These results suggest recent secondary contact of 2 differentiated taxa following expansion from allopatric Pleistocene refugia. We modeled the transition in haplotype frequencies along the Florida peninsula as a zone of neutral introgression; the estimated width of that zone was 435 km, and its center was near present day Ocala. Variation in plumage pattern along the peninsula previously had been used to describe a subspecific taxon, M. c. perplexus. We used variation in the forehead pattern of adult males from along the east coast of the United States to model this phenotypic transition; the zone had an estimated width of >2,500 km and an approximate center in the Florida Keys. Taken together, the geographic patterns in mtDNA and plumage variation suggest the populations of Red-bellied Woodpeckers on the Florida peninsula differentiated from those elsewhere during isolation; they are now in secondary contact in a well-known suture zone and represent 2 phylogenetic species connected by wide molecular and morphological zones of introgression. Received 11 May 2017. Accepted 21 November 2017. Key words: hybrid zones, Melanerpes carolinus, ND2, phylogeny, phylogeography, suture zones, TGFB-2. Utilizamos secuencias del gene mitocondrial ND2, intron-5 TGFB-2 nuclear, y diferencias en patrones de plumaje para analizar la variacion geografica del Carpintero de Carolina (Melanerpes carolinus). Diez muestras de todo su rango indicaron que aproximadamente 23% de la variacion genetica mitocondrial se distribuyo entre poblaciones; esto fue debido en gran parte a la ocurrencia de un ciado de haplotipos restringidos en la Peninsula de Florida, con una frecuencia local de 82%. En el analisis jerarquico, 37% de la varianza genetica de ADNmt se distribuyo entre la Peninsula de Florida y otros lugares. Hubo una fuerte senal de crecimiento poblacional en la parte no peninsular del rango. De lo contrario, hubo una variacion geografica menor en las frecuencias de haplotipos y no hubo evidencia de aislamiento por distancia. Los datos del intron nuclear mostraron poca variacion entre poblaciones (F.sub.st = 0.007). Estos resultados sugieren un contacto secundario reciente de dos taxones diferenciados despues de la expansion de los refugios pleistocenicos alopatricos. Modelamos la transicion de frecuencias haplotipicas entre la Peninsula de Florida como una zona de introgresion neutral; el ancho estimado de esta zona fue de 435 km y su centro estaba cerca de la actual Ocala. Variacion en el patron de plumaje entre la peninsula ha sido previamente usado para describir un taxon subespecifico, M. c. perplexus. Utilizamos la variacion en el patron de la frente de los machos adultos a lo largo de la costa este de los EE.UU para modelar esta transicion fenotipica; la zona tenia un ancho estimado de mas de 2,500 km y un centro aproximado en los Cayos de Florida. Tomados en conjunto, los patrones geograficos en DNAmt y la variacion del plumaje, sugieren que la poblacion de Carpinteros de Carolina en la Peninsula de Florida y aquellos en otros lugares diferenciados en aislamiento, ahora estan en contacto secundario en una zona de sutura conocida, y representan dos especies filogeneticamente conectadas por amplias zonas de introgresion moleculares y morfologicas. Palabras clave: filogenia, filogeografia, Melanerpes carolinus, ND2, TGFB-2, zonas hibridas, zonas de sutura.
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