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1.
Ann Bot ; 132(1): 43-60, 2023 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-37279362

RESUMEN

BACKGROUND AND AIMS: Few studies of angiosperms have focused on androecial evolution in conjunction with evolutionary shifts in corolla morphology and pollinator relationships. The Western Hemisphere clade of Justiciinae (Acanthaceae) presents the rare opportunity to examine remarkable diversity in staminal morphology. We took a phylogenetically informed approach to examine staminal diversity in this hypervariable group and asked whether differences in anther thecae separation is associated with phylogenetically informed patterns of variation in corolla morphology. We further discuss evidence for associations between anther diversity and pollinators in this lineage. METHODS: For the Dianthera/Sarotheca/Plagiacanthus (DSP) clade of Western Hemisphere Justiciinae, we characterized floral diversity based on a series of corolla measurements and using a model-based clustering approach. We then tested for correlations between anther thecae separation and corolla traits, and for shifts in trait evolution, including evidence for convergence. KEY RESULTS: There is evolutionary vagility in corolla and anther traits across the DSP clade with little signal of phylogenetic constraint. Floral morphology clusters into four distinct groups that are, in turn, strongly associated with anther thecae separation, a novel result in Acanthaceae and, to our knowledge, across flowering plants. These cluster groups are marked by floral traits that strongly point to associations with pollinating animals. Specifically, species that are known or likely to be hummingbird pollinated have stamens with parallel thecae, whereas those that are likely bee or fly pollinated have stamens with offset, divergent thecae. CONCLUSIONS: Our results suggest that anther thecae separation is likely under selection in concert with other corolla characters. Significant morphological shifts detected by our analyses corresponded to putative shifts from insect to hummingbird pollination. Results from this study support the hypothesis that floral structures function in an integrated manner and are likely subject to selection as a suite. Further, these changes can be hypothesized to represent adaptive evolution.


Asunto(s)
Acanthaceae , Magnoliopsida , Abejas , Animales , Filogenia , Evolución Biológica , Flores/anatomía & histología , Insectos , Polinización , Aves
2.
Am J Bot ; 104(11): 1729-1744, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-29158342

RESUMEN

PREMISE OF THE STUDY: Following establishment after long-distance dispersal, species may experience stasis, accumulate changes leading to new species identity, diversify into multiple species, interact with related species to form novel species, and even become extirpated. We examined each species of temperate Polemoniaceae in South America via the literature and new analyses to better understand the fates of species in this family after their dispersal from North America. METHODS: We reviewed literature for the 15 species of Polemoniaceae in South America amphitropically disjunct from their relatives in North America. We conducted DNA sequence analyses to infer relationships, timing of dispersal, and processes involved since dispersal in Microsteris gracilis, three Gilia, two Giliastrum, and three Collomia. Analyses included construction of haplotype networks and phylogenetic trees using maximum likelihood and Bayesian inference. KEY RESULTS: For all species examined in detail, origins in South America are compatible with dispersal via epizoochory from ca. 0.092-19.46 million years ago. Most species in South America are unique relative to their North American congeners, yet few have radiated into two or more species. Relative stasis, divergence, and hybridization with, and without, allopolyploid formation have occurred postdispersal in Polemoniaceae, as well as extirpation following at least brief establishment. CONCLUSIONS: Polemoniaceae that have established in South America share many features likely inherited from their North American progenitors, but some traits may have arisen in situ in specific taxa, such as cleistogamy, self-incompatibility, and the annual habit, evidencing the rich nature of diversification processes.


Asunto(s)
Magnoliopsida/fisiología , Dispersión de las Plantas , Teorema de Bayes , Hibridación Genética , Magnoliopsida/genética , América del Norte , Fenotipo , Filogenia , Semillas/genética , Semillas/fisiología , Análisis de Secuencia de ADN , América del Sur
3.
Front Plant Sci ; 12: 725900, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34721456

RESUMEN

The evolutionary relationships of Salvia have been difficult to estimate. In this study, we used the Next Generation Sequencing method Hyb-Seq to evaluate relationships among 90 Lamiaceae samples, including representatives of Mentheae, Ocimeae, Salvia subgenera Audibertia, Leonia, Salvia, and 69 species of subgenus Calosphace, representing 32 of Epling's sections. A bait set was designed in MarkerMiner using available transcriptome data to enrich 119 variable nuclear loci. Nuclear and chloroplast loci were assembled with hybphylomaker (HPM), followed by coalescent approach analyses for nuclear data (ASTRAL, BEAST) and a concatenated Maximum Likelihood analysis of chloroplast loci. The HPM assembly had an average of 1,314,368 mapped reads for the sample and 527 putative exons. Phylogenetic inferences resolved strongly supported relationships for the deep-level nodes, agreeing with previous hypotheses which assumed that subgenus Audibertia is sister to subgenus Calosphace. Within subgenus Calosphace, we recovered eight monophyletic sections sensu Epling, Cardinalis, Hastatae, Incarnatae, and Uricae in all the analyses (nDNA and cpDNA), Biflorae, Lavanduloideae, and Sigmoideae in nuclear analyses (ASTRAL, BEAST) and Curtiflorae in ASTRAL trees. Network analysis supports deep node relationships, some of the main clades, and recovers reticulation within the core Calosphace. The chloroplast phylogeny resolved deep nodes and four monophyletic Calosphace sections. Placement of S. axillaris is distinct in nuclear evidence and chloroplast, as sister to the rest of the S. subg. Calosphace in chloroplast and a clade with "Hastatae clade" sister to the rest of the subgenus in nuclear evidence. We also tested the monophyly of S. hispanica, S. polystachia, S. purpurea, and S. tiliifolia, including two samples of each, and found that S. hispanica and S. purpurea are monophyletic. Our baits can be used in future studies of Lamiaceae phylogeny to estimate relationships between genera and among species. In this study, we presented a Hyb-Seq phylogeny for complex, recently diverged Salvia, which could be implemented in other Lamiaceae.

4.
Work ; 33(3): 335-44, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19759432

RESUMEN

This paper describes research carried out at Loughborough University in the UK into the areas of 'design for all' and accessible transport. The research addresses two common needs for designers and ergonomists working towards developing more inclusive products and environments, namely data on users that is accessible, valid, and applicable and a means of utilising the data to assess the accessibility of designs during the early stages of development. HADRIAN is a computer-based inclusive design tool that has been developed to support designers in their efforts to develop products that meet the needs of a broader range of users. Currently HADRIAN is being expanded to support transport design. This includes data on an individual's ability to undertake a variety of transport-related tasks, such as vehicle ingress/egress, coping with uneven surfaces, steps, street furniture and complex pedestrian environments. The subsequent use of this data will be supported either through a task analysis system that will allow a designer to evaluate a design for a part of the transport infrastructure (ticket barrier, train carriage etc.), or alternatively allow the designer or an end user to evaluate a whole journey. The 'journey planner' feature of the HADRIAN tool will compare an individual's physical, cognitive and emotional abilities with the demands placed upon that individual by the mode(s) of transport available and the route options selected. It is envisaged that these developments will prove extremely useful to users, designers, planners and all those involved with transport use and implementation.


Asunto(s)
Diseño Asistido por Computadora , Ergonomía/métodos , Transportes/instrumentación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Bases de Datos como Asunto , Personas con Discapacidad , Diseño de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reino Unido , Adulto Joven
5.
Evolution ; 60(9): 1777-92, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17089963

RESUMEN

Adaptive diversification can be viewed as a balance between the conservative force of interpopulation gene flow and selection for differential environments. In this paper, we examine ecological, morphological, and genetic differentiation in a small clade consisting of four East Maui-endemic species of Dubautia: D. menziesii, D. platyphylla, D. reticulata, and D. waianapanapaensis, in the Hawaiian silversword alliance (Asteraceae). The East Maui clade is apparently recently derived (less than 1 million years ago) and is geographically restricted yet displays significant ecological and morphological differences. We used geographic data from historical herbarium specimens, measurements of plant architecture and leaf morphometrics, and measures of genetic differentiation in both microsatellite and nuclear coding loci to examine the correlation of different forms of divergence in this small species flock. We found overlap in large-scale geographic distributions, significant differentiation in most habitat factors, significant microsatellite differentiation, and many shared alleles at nuclear coding loci suggesting on-going lineage sorting. Despite the presence of apparent hybrids in some populations, microsatellite variation is consistent with isolation among species. Using Mantel tests, we compared the direction and extent of diversification among different datasets, to determine whether ecological/morphological divergence was correlated with genetic divergence. Correlations among different datasets showed that habitat was strongly correlated with plant architecture but not leaf morphology. Taken together, these results indicate that ecological and morphological diversification has driven genetic divergence at rapidly evolving microsatellite loci, whereas there is continuing lineage sorting at neutral sites in nuclear coding loci.


Asunto(s)
Asteraceae/genética , Ecosistema , Especiación Genética , Adaptación Fisiológica , ADN de Plantas/genética , Variación Genética , Hawaii , Repeticiones de Microsatélite , Filogenia , Hojas de la Planta/anatomía & histología , Hojas de la Planta/genética , Especificidad de la Especie
6.
Appl Ergon ; 34(3): 207-14, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12737920

RESUMEN

An objective measure that will predict discomfort reliably, and which can be used at an early stage in the development of a vehicle and its seating, would have the potential to reduce the prevalence of musculoskeletal problems associated with driving. This paper reports on an extended road trial study to further investigate the potential value of pressure distribution data in the prediction of reported discomfort. Road trial data were collected from three cars and then interface pressure data were recorded for each of the three seats. Clear differences were identified between the cars with respect to reports of discomfort. However, no clear relationship was found between interface pressure data and reported discomfort.


Asunto(s)
Conducción de Automóvil , Ergonomía , Sistema Musculoesquelético/fisiopatología , Femenino , Humanos , Masculino , Dolor , Presión , Reino Unido
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