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1.
J Evol Biol ; 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38847298

RESUMEN

Interspecific variation in body size is one of the most popular topics in comparative studies. Despite recent advances, little is still known about the patterns and processes behind the evolution of body size in insects. Here, we used a robust data set comprising all geometrid moth species occurring in Northern Europe to examine the evolutionary associations involving body size and several life-history traits under an explicitly phylogenetic framework. We provided new insights into the interactive effects of life-history traits on body size and evidence of correlated evolution. We further established the sequence of trait evolution linking body size with the life-history traits correlated with it. We found that most (but not all) of the studied life-history traits, to some extent, interfered with interspecific variation in body size, but interactive effects were uncommon. Both bi- and multivariate phylogenetic analyses indicated that larger species tend to be nocturnal flyers, overwinter in the larval stage, feed on the foliage of trees rather than herbs, and have a generalist feeding behavior. We found evidence of correlated evolution involving body size with overwintering stage, host-plant growth form, and dietary specialization. The examination of evolutionary transitions within the correlated models signaled that overwintering as larvae preceded the evolution of large sizes, as did feeding on tree foliage and the generalist feeding behavior. By showing that both body size and all life-history traits correlated with it evolve at very slow rates, we caution against uncritical attempts to propose causal explanations for respective associations based on contemporary ecological settings.

2.
Ecol Lett ; 26(11): 1862-1876, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37766496

RESUMEN

Mycorrhizal symbioses are known to strongly influence plant performance, structure plant communities and shape ecosystem dynamics. Plant mycorrhizal traits, such as those characterising mycorrhizal type (arbuscular (AM), ecto-, ericoid or orchid mycorrhiza) and status (obligately (OM), facultatively (FM) or non-mycorrhizal) offer valuable insight into plant belowground functionality. Here, we compile available plant mycorrhizal trait information and global occurrence data ( ∼ 100 million records) for 11,770 vascular plant species. Using a plant phylogenetic mega-tree and high-resolution climatic and edaphic data layers, we assess phylogenetic and environmental correlates of plant mycorrhizal traits. We find that plant mycorrhizal type is more phylogenetically conserved than plant mycorrhizal status, while environmental variables (both climatic and edaphic; notably soil texture) explain more variation in mycorrhizal status, especially FM. The previously underestimated role of environmental conditions has far-reaching implications for our understanding of ecosystem functioning under changing climatic and soil conditions.


Asunto(s)
Micorrizas , Micorrizas/genética , Ecosistema , Filogenia , Microbiología del Suelo , Plantas , Suelo/química
3.
Ecol Lett ; 24(8): 1569-1581, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34110065

RESUMEN

Identifying environmental predictors of phenotype is fundamentally important to many ecological questions, from revealing broadscale ecological processes to predicting extinction risk. However, establishing robust environment-phenotype relationships is challenging, as powerful case studies require diverse clades which repeatedly undergo environmental transitions at multiple taxonomic scales. Actinopterygian fishes, with 32,000+ species, fulfil these criteria for the fundamental habitat divisions in water. With four datasets of body size (ranging 10,905-27,226 species), I reveal highly consistent size-by-habitat-use patterns across nine scales of observation. Taxa in marine, marine-brackish, euryhaline and freshwater-brackish habitats possess larger mean sizes than freshwater relatives, and the largest mean sizes consistently emerge within marine-brackish and euryhaline taxa. These findings align with the predictions of seven mechanisms thought to drive larger size by promoting additional trophic levels. However, mismatches between size and trophic-level patterns highlight a role for additional mechanisms, and support for viable candidates is examined in 3439 comparisons.


Asunto(s)
Ecosistema , Peces , Animales , Tamaño Corporal , Agua Dulce
4.
Mol Phylogenet Evol ; 162: 107198, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33989807

RESUMEN

Understanding how and why some groups have become more species-rich than others, and how past biogeography may have shaped their current distribution, are questions that evolutionary biologists have long attempted to answer. We investigated diversification patterns and historical biogeography of a hyperdiverse lineage of Lepidoptera, the geometrid moths, by studying its most species-rich tribe Boarmiini, which comprises ca. 200 genera and ca. known 3000 species. We inferred the evolutionary relationships of Boarmiini based on a dataset of 346 taxa, with up to eight genetic markers under a maximum likelihood approach. The monophyly of Boarmiini is strongly supported. However, the phylogenetic position of many taxa does not agree with current taxonomy, although the monophyly of most major genera within the tribe is supported after minor adjustments. Three genera are synonymized, one new combination is proposed, and four species are placed in incertae sedis within Boarmiini. Our results support the idea of a rapid initial diversification of Boarmiini, which also implies that no major taxonomic subdivisions of the group can currently be proposed. A time-calibrated tree and biogeographical analyses suggest that boarmiines appeared in Laurasia ca. 52 Mya, followed by dispersal events throughout the Australasian, African and Neotropical regions. Most of the transcontinental dispersal events occurred in the Eocene, a period of intense geological activity and rapid climate change. Diversification analyses showed a relatively constant diversification rate for all Boarmiini, except in one clade containing the species-rich genus Cleora. The present work represents a substantial contribution towards understanding the evolutionary origin of Boarmiini moths. Our results, inevitably biased by taxon sampling, highlight the difficulties with working on species-rich groups that have not received much attention outside of Europe. Specifically, poor knowledge of the natural history of geometrids (particularly in tropical clades) limits our ability to identify key innovations underlying the diversification of boarmiines.


Asunto(s)
Evolución Molecular , Mariposas Nocturnas/clasificación , Filogenia , Filogeografía , Animales , Europa (Continente) , Femenino , Funciones de Verosimilitud , Mariposas Nocturnas/genética
5.
Proc Natl Acad Sci U S A ; 113(41): 11531-11536, 2016 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-27671652

RESUMEN

Since Darwin, biologists have been struck by the extraordinary diversity of teleost fishes, particularly in contrast to their closest "living fossil" holostean relatives. Hypothesized drivers of teleost success include innovations in jaw mechanics, reproductive biology and, particularly at present, genomic architecture, yet all scenarios presuppose enhanced phenotypic diversification in teleosts. We test this key assumption by quantifying evolutionary rate and capacity for innovation in size and shape for the first 160 million y (Permian-Early Cretaceous) of evolution in neopterygian fishes (the more extensive clade containing teleosts and holosteans). We find that early teleosts do not show enhanced phenotypic evolution relative to holosteans. Instead, holostean rates and innovation often match or can even exceed those of stem-, crown-, and total-group teleosts, belying the living fossil reputation of their extant representatives. In addition, we find some evidence for heterogeneity within the teleost lineage. Although stem teleosts excel at discovering new body shapes, early crown-group taxa commonly display higher rates of shape evolution. However, the latter reflects low rates of shape evolution in stem teleosts relative to all other neopterygian taxa, rather than an exceptional feature of early crown teleosts. These results complement those emerging from studies of both extant teleosts as a whole and their sublineages, which generally fail to detect an association between genome duplication and significant shifts in rates of lineage diversification.


Asunto(s)
Evolución Biológica , Peces/clasificación , Fósiles , Animales , Tamaño Corporal , Peces/genética , Duplicación de Gen , Fenotipo , Filogenia , Factores de Tiempo
6.
New Phytol ; 192(1): 266-301, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21729086

RESUMEN

• Plants have utterly transformed the planet, but testing hypotheses of causality requires a reliable time-scale for plant evolution. While clock methods have been extensively developed, less attention has been paid to the correct interpretation and appropriate implementation of fossil data. • We constructed 17 calibrations, consisting of minimum constraints and soft maximum constraints, for divergences between model representatives of the major land plant lineages. Using a data set of seven plastid genes, we performed a cross-validation analysis to determine the consistency of the calibrations. Six molecular clock analyses were then conducted, one with the original calibrations, and others exploring the impact on divergence estimates of changing maxima at basal nodes, and prior probability densities within calibrations. • Cross-validation highlighted Tracheophyta and Euphyllophyta calibrations as inconsistent, either because their soft maxima were overly conservative or because of undetected rate variation. Molecular clock analyses yielded estimates ranging from 568-815 million yr before present (Ma) for crown embryophytes and from 175-240 Ma for crown angiosperms. • We reject both a post-Jurassic origin of angiosperms and a post-Cambrian origin of land plants. Our analyses also suggest that the establishment of the major embryophyte lineages occurred at a much slower tempo than suggested in most previous studies. These conclusions are entirely compatible with current palaeobotanical data, although not necessarily with their interpretation by palaeobotanists.


Asunto(s)
Evolución Biológica , Magnoliopsida/genética , Calibración , Fósiles , Modelos Genéticos , Filogenia , Reproducibilidad de los Resultados , Factores de Tiempo
7.
Nature ; 472(7343): 331-3, 2011 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-21512570

RESUMEN

Although there are substantial differences between the magnetospheres of Jupiter and Saturn, it has been suggested that cryovolcanic activity at Enceladus could lead to electrodynamic coupling between Enceladus and Saturn like that which links Jupiter with Io, Europa and Ganymede. Powerful field-aligned electron beams associated with the Io-Jupiter coupling, for example, create an auroral footprint in Jupiter's ionosphere. Auroral ultraviolet emission associated with Enceladus-Saturn coupling is anticipated to be just a few tenths of a kilorayleigh (ref. 12), about an order of magnitude dimmer than Io's footprint and below the observable threshold, consistent with its non-detection. Here we report the detection of magnetic-field-aligned ion and electron beams (offset several moon radii downstream from Enceladus) with sufficient power to stimulate detectable aurora, and the subsequent discovery of Enceladus-associated aurora in a few per cent of the scans of the moon's footprint. The footprint varies in emission magnitude more than can plausibly be explained by changes in magnetospheric parameters--and as such is probably indicative of variable plume activity.

8.
Science ; 318(5848): 229-31, 2007 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-17932286

RESUMEN

Observations of Jupiter's nightside airglow (nightglow) and aurora obtained during the flyby of the New Horizons spacecraft show an unexpected lack of ultraviolet nightglow emissions, in contrast to the case during the Voyager flybys in 1979. The flux and average energy of precipitating electrons generally decrease with increasing local time across the nightside, consistent with a possible source region along the dusk flank of Jupiter's magnetosphere. Visible emissions associated with the interaction of Jupiter and its satellite Io extend to a surprisingly high altitude, indicating localized low-energy electron precipitation. These results indicate that the interaction between Jupiter's upper atmosphere and near-space environment is variable and poorly understood; extensive observations of the day side are no guide to what goes on at night.


Asunto(s)
Júpiter , Medio Ambiente Extraterrestre , Hidrocarburos , Hidrógeno , Magnetismo , Nave Espacial
9.
JAMA ; 251(21): 3080-2, 1985 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-11652448

RESUMEN

KIE: The transition from a fee-for-service model to a prepaid health care system can sometimes result in stresses for both physicians and patients. Both could feel trapped as patients approach the system with objectives that may be unrealistic, while physicians feel threatened or suspect that patients are abusing the services. Based on their experience in a large multispecialty academic group practice, the authors have developed management strategies to improve the physician patient relationship in prepaid care settings. These include review of marketing efforts, patient education to foster realistic expectations, a policy for dealing with dissatisfied patients and physicians, a strong central administrative physician to resolve differences of opinion, and continuing physician orientation and education to improve judgment and attitudes.^ieng


Asunto(s)
Actitud , Atención a la Salud , Economía , Sistemas Prepagos de Salud , Relaciones Médico-Paciente , Personal Administrativo , Honorarios y Precios , Humanos , Cooperación del Paciente , Rol del Médico , Estrés Psicológico
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