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1.
PhytoKeys ; 222: 75-127, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37252638

RESUMO

In preparation for a full taxonomic revision of the Neotropical genera of Costaceae (i.e., Chamaecostus, Costus, Dimerocostus, and Monocostus), we present the description of 17 new species of Neotropical Costus and one new species of the Neotropic endemic genus Chamaecostus with notes on their distribution and ecology, vernacular names (when known), and diagnostic characters for identification. Distribution maps are included for all species, and each description is accompanied by photographic plates illustrating diagnostic characters.

2.
Front Plant Sci ; 13: 874322, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36161003

RESUMO

Selection together with variation in floral traits can act to mold floral form, often driven by a plant's predominant or most effective pollinators. To investigate the evolution of traits associated with pollination, we developed a phylogenetic framework for evaluating tempo and mode of pollination shifts across the genus Costus L., known for its evolutionary toggle between traits related to bee and bird pollination. Using a target enrichment approach, we obtained 957 loci for 171 accessions to expand the phylogenetic sampling of Neotropical Costus. In addition, we performed whole genome resequencing for a subset of 20 closely related species with contrasting pollination syndromes. For each of these 20 genomes, a high-quality assembled transcriptome was used as reference for consensus calling of candidate loci hypothesized to be associated with pollination-related traits of interest. To test for the role these candidate genes may play in evolutionary shifts in pollinators, signatures of selection were estimated as dN/dS across the identified candidate loci. We obtained a well-resolved phylogeny for Neotropical Costus despite conflict among gene trees that provide evidence of incomplete lineage sorting and/or reticulation. The overall topology and the network of genome-wide single nucleotide polymorphisms (SNPs) indicate that multiple shifts in pollination strategy have occurred across Costus, while also suggesting the presence of previously undetected signatures of hybridization between distantly related taxa. Traits related to pollination syndromes are strongly correlated and have been gained and lost in concert several times throughout the evolution of the genus. The presence of bract appendages is correlated with two traits associated with defenses against herbivory. Although labellum shape is strongly correlated with overall pollination syndrome, we found no significant impact of labellum shape on diversification rates. Evidence suggests an interplay of pollination success with other selective pressures shaping the evolution of the Costus inflorescence. Although most of the loci used for phylogenetic inference appear to be under purifying selection, many candidate genes associated with functional traits show evidence of being under positive selection. Together these results indicate an interplay of phylogenetic history with adaptive evolution leading to the diversification of pollination-associated traits in Neotropical Costus.

3.
Nat Hum Behav ; 5(1): 159-169, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33398150

RESUMO

Over the past 10 years, Oosterhof and Todorov's valence-dominance model has emerged as the most prominent account of how people evaluate faces on social dimensions. In this model, two dimensions (valence and dominance) underpin social judgements of faces. Because this model has primarily been developed and tested in Western regions, it is unclear whether these findings apply to other regions. We addressed this question by replicating Oosterhof and Todorov's methodology across 11 world regions, 41 countries and 11,570 participants. When we used Oosterhof and Todorov's original analysis strategy, the valence-dominance model generalized across regions. When we used an alternative methodology to allow for correlated dimensions, we observed much less generalization. Collectively, these results suggest that, while the valence-dominance model generalizes very well across regions when dimensions are forced to be orthogonal, regional differences are revealed when we use different extraction methods and correlate and rotate the dimension reduction solution. PROTOCOL REGISTRATION: The stage 1 protocol for this Registered Report was accepted in principle on 5 November 2018. The protocol, as accepted by the journal, can be found at https://doi.org/10.6084/m9.figshare.7611443.v1 .


Assuntos
Percepção Social/etnologia , Adolescente , Adulto , Comparação Transcultural , Emoções , Expressão Facial , Humanos , Julgamento , Masculino , Modelos Psicológicos , Percepção Social/psicologia , Adulto Jovem
4.
Front Plant Sci ; 11: 1195, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32922414

RESUMO

The family of pantropical spiral gingers (Costaceae Nakai; c. 125 spp.) can be used as a model to enhance our understanding of the mechanisms underlying Neotropical diversity. Costaceae has higher taxonomic diversity in South and Central America (c. 72 Neotropical species, c. 30 African, c. 23 Southeast Asian), particularly due to a radiation of Neotropical species of the genus Costus L. (c. 57 spp.). However, a well-supported phylogeny of the Neotropical spiral gingers including thorough sampling of proposed species encompassing their full morphologic and geographic variation is lacking, partly due to poor resolution recovered in previous analyses using a small sampling of loci. Here we use a phylogenomic approach to estimate the phylogeny of a sample of Neotropical Costus species using a targeted enrichment approach. Baits were designed to capture conserved elements' variable at the species level using available genomic sequences of Costus species and relatives. We obtained 832 loci (generating 791,954 aligned base pairs and 31,142 parsimony informative sites) for samples that encompassed the geographical and/or morphological diversity of some recognized species. Higher support values that improve the results of previous studies were obtained when including all the available loci, even those producing unresolved gene trees and having a low proportion of variable sites. Concatenation and coalescent-based species trees methods converge in almost the same topology suggesting a robust estimation of the relationships, even under the high levels of gene tree conflict presented here. The bait set design here presented made inferring a robust phylogeny to test taxonomic hypotheses possible and will improve our understanding of the origins of the charismatic diversity of the Neotropical spiral gingers.

5.
Sci Rep ; 10(1): 4391, 2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-32152353

RESUMO

Body height is a life-history component. It involves important costs for its expression and maintenance, which may originate trade-offs on other costly components such as reproduction or immunity. Although previous evidence has supported the idea that human height could be a sexually selected trait, the explanatory mechanisms that underlie this selection are poorly understood. Despite extensive studies on the association between height and attractiveness, the role of immunity in linking this relation is scarcely studied, particularly in non-Western populations. Here, we tested whether human height is related to health measured by self-perception, and relevant nutritional and health anthropometric indicators in three Latin-American populations that widely differ in socioeconomic and ecological conditions: two urbanised populations from Bogota (Colombia) and Mexico City (Mexico), and one isolated indigenous population (Me'Phaa, Mexico). Results showed that self-reported health is best predicted by an interaction between height and waist circumference: the presumed benefits of being taller are waist-dependent, and affect taller people more than shorter individuals. If health and genetic quality cues play an important role in human mate-choice, and height and waist interact to signal health, its evolutionary consequences, including cognitive and behavioural effects, should be addressed in future research.


Assuntos
Pesos e Medidas Corporais , População Rural , Autorrelato , População Urbana , Adulto , Feminino , Hispânico ou Latino , Humanos , Masculino , Grupos Populacionais , Vigilância da População , Estados Unidos/epidemiologia , Adulto Jovem
6.
Mol Phylogenet Evol ; 119: 13-24, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28987636

RESUMO

The reconstruction of relationships within species-rich groups that have recently evolved in biodiversity hotspots is hampered by a lack of phylogenetically informative markers. It is also made difficult by the lack of sampling necessary to reconstruct a species-level phylogeny. We use transcriptome mining to search for markers to reconstruct a phylogeny of the amphi-Atlantic genus Renealmia L. f. (Zingiberaceae). We recover seven introns from single copy genes and use them to reconstruct the phylogeny of the genus together with a commonly used phylogenetic marker, internal transcribed spacers of ribosomal DNA (ITS) that has previously been used to reconstruct the phylogeny of the genus. We targeted genes with low numbers of base pairs that improves sequencing success using highly degraded DNA from herbarium specimens. The use of herbarium specimens greatly increased the number of species in the study as these were readily available in historical collections. Data were obtained for 14 of the 17 African species and 54 of the 65 Neotropical species. The phylogeny was well-supported for a number of Renealmia subgroups although relationships among those clades remained poorly supported.


Assuntos
Filogenia , Transcriptoma/genética , Clima Tropical , Zingiberaceae/classificação , Zingiberaceae/genética , Teorema de Bayes , DNA Ribossômico/genética , Marcadores Genéticos , Íntrons/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Análise de Sequência de DNA , Especificidade da Espécie
7.
Mol Phylogenet Evol ; 94(Pt B): 626-634, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26456003

RESUMO

Megascops screech-owls are endemic to the New World and range from southern Canada to the southern cone of South America. The 22 currently recognized Megascops species occupy a wide range of habitats and elevations, from desert to humid montane forest, and from sea level to the Andean tree line. Species and subspecies diagnoses of Megascops are notoriously difficult due to subtle plumage differences among taxa with frequent plumage polymorphism. Using three mitochondrial and three nuclear genes we estimated a phylogeny for all but one Megascops species. Phylogenies were estimated with Maximum Likelihood and Bayesian Inference, and a Bayesian chronogram was reconstructed to assess the spatio-temporal context of Megascops diversification. Megascops was paraphyletic in the recovered tree topologies if the Puerto Rican endemic M. nudipes is included in the genus. However, the remaining taxa are monophyletic and form three major clades: (1) M. choliba, M. koepckeae, M. albogularis, M. clarkii, and M. trichopsis; (2) M. petersoni, M. marshalli, M. hoyi, M. ingens, and M. colombianus; and (3) M. asio, M. kennicottii, M. cooperi, M. barbarus, M. sanctaecatarinae, M. roboratus, M. watsonii, M. atricapilla, M. guatemalae, and M. vermiculatus. Megascops watsonii is paraphyletic with some individuals more closely related to M. atricapilla than to other members in that polytypic species. Also, allopatric populations of some other Megascops species were highly divergent, with levels of genetic differentiation greater than between some recognized species-pairs. Diversification within the genus is hypothesized to have taken place during the last 8 million years, with a likely origin in Central America. The genus later expanded over much of the Americas and then diversified via multiple dispersal events from the Andes into the Neotropical lowlands.


Assuntos
DNA Mitocondrial/genética , Variação Genética , Filogenia , Estrigiformes/classificação , Animais , Teorema de Bayes , Canadá , América Central , Ecossistema , Funções Verossimilhança , América do Sul , Estrigiformes/genética
9.
Front Genet ; 5: 362, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25520736

RESUMO

Species diversity is unequally distributed across the globe, with the greatest concentration occurring in the tropics. Even within the tropics, there are significant differences in the numbers of taxa found in each continental region. Manilkara is a pantropical genus of trees in the Sapotaceae comprising c. 78 species. Its distribution allows for biogeographic investigation and testing of whether rates of diversification differ amongst tropical regions. The age and geographical origin of Manilkara are inferred to determine whether Gondwanan break-up, boreotropical migration or long distance dispersal have shaped its current disjunct distribution. Diversification rates through time are also analyzed to determine whether the timing and tempo of speciation on each continent coincides with geoclimatic events. Bayesian analyses of nuclear (ITS) and plastid (rpl32-trnL, rps16-trnK, and trnS-trnFM) sequences were used to reconstruct a species level phylogeny of Manilkara and related genera in the tribe Mimusopeae. Analyses of the nuclear data using a fossil-calibrated relaxed molecular clock indicate that Manilkara evolved 32-29 million years ago (Mya) in Africa. Lineages within the genus dispersed to the Neotropics 26-18 Mya and to Asia 28-15 Mya. Higher speciation rates are found in the Neotropical Manilkara clade than in either African or Asian clades. Dating of regional diversification correlates with known palaeoclimatic events. In South America, the divergence between Atlantic coastal forest and Amazonian clades coincides with the formation of drier Cerrado and Caatinga habitats between them. In Africa diversification coincides with Tertiary cycles of aridification and uplift of the east African plateaux. In Southeast Asia dispersal may have been limited by the relatively recent emergence of land in New Guinea and islands further east c. 10 Mya.

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