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1.
Curr Biol ; 34(1): 183-189.e4, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-38035884

RESUMO

To glide in forest canopies, arboreal vertebrates evolved various skin-derived aerodynamic structures, such as patagial membranes or webbing, but no comparable structure has been reported from wingless arboreal arthropods.1,2,3 Orchid mantises (Hymenopus coronatus) have been traditionally considered a textbook example of flower mimicry for ∼200 years due to their highly expanded, petal-shaped femoral lobes. However, the empirical evidence substantiating the petal-mimicry function of the femoral lobes has not been entirely conclusive.4,5,6 Observational and experimental evidence suggests that these lobes do not contribute to flower mimicry for luring pollinators6,7 and likely serve other functions.7,8 After observing their aerial escape initiated with active jumping, we hypothesized that orchid mantises can glide and that their femoral lobes are used for gliding. Through behavioral investigations and morphological analyses, we show that orchid mantis nymphs are excellent gliders, exhibiting the shallowest gliding trajectories observed in terrestrial invertebrates.9,10,11,12,13 The lobe extensions on their femoral segments are cambered airfoils, which increase the mantis projected area by ∼36% and play a vital role in the aerodynamic underpinning of the observed gliding. Despite a 165-fold increase in body mass throughout ontogeny, older female mantis nymphs maintained a persistent gliding capability. We further showed a notable 40%-56% reduction in wing loading attributed to the positive size allometry of these lobes, indicating a clear promotion of gliding throughout ontogeny. This is the first documentation of gliding-adapted "leg wings" in a wingless arthropod. The evolution of such structures is potentially common among arboreal arthropods and demands a systematic re-examination.


Assuntos
Voo Animal , Mantódeos , Feminino , Animais , Fenômenos Biomecânicos , Florestas , Árvores
2.
J Anim Ecol ; 91(12): 2358-2369, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36169598

RESUMO

Background matching is perhaps the most ubiquitous form of defensive camouflage in the animal kingdom, an adaptive strategy that relies on the visual resemblance between a prey organism and its background to promote concealment from predators. The importance of background matching has been acknowledged for over a century, yet despite its renown and apparent pervasiveness, few studies exist that have objectively quantified its occurrence and tested the functional significance of background matching in a specific animal study system. The North Island lichen moth Declana atronivea presents a fascinating system to investigate such anti-predator coloration. This species possesses high contrast black and white forewings that appear to resemble lichen. Here we assessed the contribution of background matching to the antipredator defence of D. atronivea using field predation experiments with realistic models. We found that D. atronivea coloration confers a significant survival advantage against native avian predators when on lichen backgrounds compared to bark backgrounds, with an intermediate level of predation occurring when models were near, but not on lichen. This suggests that D. atronivea wing patterns are an adaptation for background matching. We subsequently used calibrated digital photography, avian vision modelling and image analysis techniques to objectively quantify the degree of background matching exhibited by D. atronivea and assessed the contribution of different visual elements (colour, luminance and pattern) to camouflage in this species. Only the pattern elements of D. atronivea presented a close match to that of the lichen backgrounds, with both chromatic and achromatic cues found to be poor predictors of background matching in this species. This study is one of the first to integrate vision modelling, quantitative image analysis and field predation experiments using realistic models to objectively quantify the level and functional significance of background matching in a real species, and presents an ideal system for further investigating the interrelation between multiple mechanisms of camouflage.


Assuntos
Líquens , Mariposas , Animais
3.
J Card Surg ; 36(3): 1050-1055, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33336415

RESUMO

BACKGROUND: Subxiphoid incisional hernias are one of the complications following a median sternotomy, a surgical procedure to provide access to the mediastinum. Incidence has been reported between 1% and 4%, although the true incidence is not well known due to its asymptomatic nature. METHOD: A comprehensive search was performed on multiple sites. Keywords included "incisional hernia OR Subxiphoid hernia" AND "Median sternotomy OR Cardiac Surgery OR Coronary artery bypass graft OR Transplant OR Valve replacement". Articles up to August 1, 2020, were included in this study. RESULTS: Eight articles were included in the study, with a total number of 132 patients identified. The incidence ranged from 0.81% to 3.44%. There was a mixture of repair methods and follow-up period reported. Recurrence post repair ranged from 10% to 43%. CONCLUSION: Subxiphoid incisional hernias remain challenging to manage. We have discussed the incidence, risk factors, preventions, and management of subxiphoid incisional hernias including both the open and laparoscopic techniques.


Assuntos
Hérnia Ventral , Hérnia Incisional , Laparoscopia , Hérnia Ventral/cirurgia , Humanos , Hérnia Incisional/epidemiologia , Hérnia Incisional/cirurgia , Complicações Pós-Operatórias/epidemiologia , Recidiva , Esternotomia , Telas Cirúrgicas
4.
Proc Biol Sci ; 287(1934): 20201016, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32873210

RESUMO

Anti-predator defences are typically regarded as relatively static signals that conceal prey or advertise their unprofitability. However, startle displays are complex performances that deter or confuse predators and can include a spectacular array of movements, colours and sounds. Yet, we do not fully understand the mechanisms by which they function, their evolutionary correlates, or the conditions under which they are performed and evolve. Here, we present, to our knowledge, the first phylogenetically controlled comparative analyses of startle displays including behavioural data, using praying mantises as a model system. We included 58 species that provide a good representation of mantis diversity and estimated the strength of phylogenetic signal in the presence and complexity of displays. We also tested hypotheses on potential evolutionary correlates, including primary defences and body size. We found that startle displays and morphological traits were phylogenetically conserved, whereas behavioural traits were highly labile. Surprisingly, body size was not correlated with display presence or complexity in phylogenetically controlled analyses. Species-rich clades were more likely to exhibit displays, suggesting that startle displays were probably involved in lineage diversification. We suggest that to further elucidate the conditions under which startle displays evolve, future work should include quantitative descriptions of multiple display components, habitat type, and predator communities. Understanding the evolution of startle displays is critical to our overall understanding of the theory behind predator-prey dynamics.


Assuntos
Evolução Biológica , Mantódeos/fisiologia , Animais , Tamanho Corporal , Filogenia , Comportamento Predatório
5.
Naturwissenschaften ; 107(4): 34, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32737596

RESUMO

The egg stages of animal life cycles are underappreciated in terms of their capacity for dispersal, protection, and biotic and abiotic interactions. Some of the most intriguing egg morphologies are seen in stick and leaf insects (Phasmatodea). Phasmids are charismatic insects, particularly due to their incredible camouflage, though a lesser-known fact is that their eggs are incredibly diverse in shape and structure, reflecting varying ecological niches. Perhaps most remarkable are those eggs which appear to resemble plant seeds in both their appearance and means of dispersal, such as via water and animal vectors. Numerous hypotheses surrounding the function of these egg morphologies and their apparent convergence with seeds have been proposed; however, empirical evidence remains lacking. Here, we present an initial synthesis of available evidence surrounding the ecology and dispersal strategies of phasmid eggs and weigh up the evidence for convergent evolution between phasmid eggs and seeds. In doing so, we highlight areas where further research is needed and discuss how the ecology of phasmid eggs may interplay with other aspects of phasmid ecology, distribution, and evolution.


Assuntos
Evolução Biológica , Neópteros/classificação , Neópteros/fisiologia , Plantas/anatomia & histologia , Plantas/classificação , Sementes/anatomia & histologia , Zigoto/citologia , Distribuição Animal/fisiologia , Animais
6.
Org Lett ; 21(18): 7289-7293, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31497960

RESUMO

The preparation of a new series of dihydridoboranes supported by N,N-chelating ligands, [R2NCH2CH2NAr]- (R = alkyl, Ar = aryl), is reported. These new boranes react selectively with carbonyls, imines, and a series of electron-deficient fluoroarenes. The reactivity is complementary to recognized reagents such as pinacolborane, catecholborane, NHC-BH3, and borane (BH3) itself. Selectivities are rationalized by invoking both open- and closed-chain forms of the reagents as part of equilibrium mixtures.

7.
Naturwissenschaften ; 105(1-2): 3, 2017 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-29209865

RESUMO

Male reproductive performance can vary with condition, age and future reproductive opportunities. Web-building spiders are ideal models to examine the effects of senescence on fitness-related behaviours due to strong selection on male courtship to reduce pre-copulatory sexual cannibalism. Argiope keyserlingi spiders generate courtship vibrations, or 'shudders', that reduce female aggression. We found that male A. keyserlingi courtship slowed with chronological age. Older males took longer to travel across the courtship thread, and overall number of shudders increased. Males retained some ability to modulate courtship quality (shudder duration and number of rocks within each shudder) in response to female quality. A change in courtship performance over time, despite strong selection for repeatability, indicates that ageing in male A. keyserlingi may have direct impacts on reproductive performance.


Assuntos
Comportamento Sexual Animal/fisiologia , Aranhas/fisiologia , Envelhecimento , Animais , Feminino , Masculino , Reprodução/fisiologia , Fatores de Tempo , Vibração
8.
Sci Rep ; 6: 37753, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27905469

RESUMO

Here we reconstruct the evolutionary shift towards floral simulation in orchid mantises and suggest female predatory selection as the likely driving force behind the development of extreme sexual size dimorphism. Through analysis of body size data and phylogenetic modelling of trait evolution, we recovered an ancestral shift towards sexual dimorphisms in both size and appearance in a lineage of flower-associated praying mantises. Sedentary female flower mantises dramatically increased in size prior to a transition from camouflaged, ambush predation to a floral simulation strategy, gaining access to, and visually attracting, a novel resource: large pollinating insects. Male flower mantises, however, remained small and mobile to facilitate mate-finding and reproductive success, consistent with ancestral male life strategy. Although moderate sexual size dimorphisms are common in many arthropod lineages, the predominant explanation is female size increase for increased fecundity. However, sex-dependent selective pressures acting outside of female fecundity have been suggested as mechanisms behind niche dimorphisms. Our hypothesised role of predatory selection acting on females to generate both extreme sexual size dimorphism coupled with niche dimorphism is novel among arthropods.


Assuntos
Evolução Biológica , Mantódeos/fisiologia , Comportamento Predatório , Seleção Genética , Caracteres Sexuais , Animais , Teorema de Bayes , Tamanho Corporal , Feminino , Masculino , Filogenia , Polinização , Análise de Regressão , Reprodução
9.
Curr Biol ; 26(4): R145-6, 2016 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-26906480

RESUMO

James O'Hanlon introduces the orchid mantis, a species of preying mantis that resembles flowers.


Assuntos
Mimetismo Biológico , Flores , Insetos/anatomia & histologia , Insetos/fisiologia , Orchidaceae , Distribuição Animal , Animais , Ásia
10.
J Chem Ecol ; 41(8): 689-95, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26245262

RESUMO

Numerous tree species' seeds contain an 'elaiosome' that acts as a food reward for ants and thus induces dispersal of the seeds. Many stick and leaf insect species appear to have evolved a convergent adaptation for dispersal whereby the egg 'capitulum' serves to induce ants to pick up and carry their eggs. Here, we investigated whether the capitulum facilitates egg dispersal by ants in the Australian stick insect Eurycnema goliath. The total fatty acid composition of E. goliath egg capsules and egg capitula were characterized to identify potential signaling compounds. Removing capitula from E. goliath eggs significantly reduced the likelihood of eggs being carried into the nests of Rhytidoponera metallica ants. Furthermore, attaching capitula to inert objects (polystyrene balls) resulted in these objects being carried into nests by R. metallica. Several fatty acids were present on the egg capsule surface in only trace amounts, whereas they made up over 10% of the dry weight of egg capitula. The fatty acid composition of egg capitula consisted mostly of palmitic acid (C16:0), linoleic acid (C18: 2n6c), oleic acid (C18:1n9c), linolenic acid (C18:3n3), and stearic acid (C18:0). Previously reported research has found that a diglyceride lipid species of oleic acid induces carrying behavior in R. metallica when added to inert artificial stimuli. Therefore, we propose that the dispersal mechanism of E. goliath eggs has converged upon the same chemical signaling pathway used by plants to exploit ant behavior.


Assuntos
Distribuição Animal , Ácidos Graxos/análise , Insetos/química , Insetos/fisiologia , Óvulo/química , Animais , Formigas/fisiologia , Comportamento Apetitivo , Austrália , Evolução Biológica , Sinais (Psicologia) , Magnoliopsida/fisiologia , Simbiose
11.
PLoS One ; 10(6): e0128755, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26107629

RESUMO

Genital asymmetry is relatively common and widespread throughout the animal kingdom. The functional significance of genital asymmetry is however, poorly understood for most species. Male praying mantids of the genus Ciulfina are remarkable in possessing complex and directionally asymmetric genital phallomeres in some species, and chirally dimorphic/antisymmetric genitalia in others. Here we explore the chiral dimorphism in male genitalia of Ciulfina baldersoni which appear to exhibit genital antisymmetry. We test whether genital orientation influences mating success, copulation duration and the attachment duration of spermatophores. Additionally we investigate genital interactions between male and females using x-ray micro-computed tomography (micro-CT) and scanning electron microscopy (SEM). Lastly we assess whether genital asymmetry is associated with non-genital morphological asymmetry of a range of traits. Our results highlight the complex functional morphology of genitalia in this praying mantis species and yet demonstrate no functional difference between dextral and sinistral morphs other than the direction of attachment with both morphs enjoying equal levels of mating success. Chiral morphs also did not strongly associate with any other forms of asymmetry. We therefore conclude that genital chirality in Ciulfina baldersoni is a likely case of antisymmetry with no functional significance to genital orientation, and is likely to be selectively neutral.


Assuntos
Copulação/fisiologia , Aptidão Genética/fisiologia , Mantódeos/fisiologia , Espermatogônias/fisiologia , Animais , Feminino , Masculino , Mantódeos/ultraestrutura , Reprodução/fisiologia , Caracteres Sexuais , Espermatogônias/ultraestrutura
12.
Ecol Evol ; 5(4): 914-20, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25750717

RESUMO

Sexually selected ornaments and signals are costly to maintain if they are maladaptive in nonreproductive contexts. The jumping spider Cosmophasis umbratica exhibits distinct sexual dichromatism with males displaying elaborate UV body markings that signal male quality. Female C. umbratica respond favorably to UV-reflecting males and ignore males that have their UV masked. However, Portia labiata, a UV-sensitive spider-eating specialist and a natural predator of C. umbratica, is known to use UV reflectance as a cue when hunting prey. We investigated the cost of these UV signals in C. umbratica in terms of their predation risk. Under experimental conditions, three choice scenarios were presented to P. labiata individuals. Choices by P. labiata were made between male C. umbratica with and without the UV signal; a UV-reflecting male and non-UV-reflecting female; and a UV-masked male and female. The presence and absence of UV signals was manipulated using an optical filter. Portia labiata exhibited a strong bias toward UV+ individuals. These results suggest the sexually selected trait of UV reflectance increases the visibility of males to UV-sensitive predators. The extent of this male-specific UV signal then is potentially moderated by predation pressure. Interestingly though, P. labiata still preferred males to females irrespective of whether UV reflectance was present or not. This suggests P. labiata can switch cues when conditions to detect UV reflectance are not optimal.

13.
Am Nat ; 183(1): 126-32, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24334741

RESUMO

Mimicry has evolved in contexts such as camouflage, predator deterrence, luring of prey, and pollinator attraction. Mimicry of flowers has until now been demonstrated only in angiosperms, yet it has been hypothesized that the Malaysian orchid mantis Hymenopus coronatus mimics a flower to attract pollinators as prey. Despite the popularity of this charismatic insect, this long-discussed hypothesis has never been experimentally investigated. We found that, as predicted for mimicry, the color of H. coronatus is indistinguishable from the color of sympatric flowers for hymenopteran pollinators. Field experiments show that isolated mantises attract wild pollinators at a rate even higher than flowers and capture these pollinators as prey items. After more than a century of conjecture, we provide the first experimental evidence of pollinator deception in the orchid mantis and the first description of a unique predatory strategy that has not been documented in any other animal species.


Assuntos
Adaptação Biológica , Insetos/fisiologia , Animais , Comportamento Animal , Cor , Feminino , Flores , Orchidaceae , Polinização
14.
Int Clin Psychopharmacol ; 18(2): 117-9, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12598825

RESUMO

We report the case of a 23-year-old woman with velocardiofacial syndrome (VCFS) and a history of psychosis and seizures. She had been treated with conventional antipsychotic and antiepileptic drugs for 10 and 3 years, respectively. However, she continued to experience occasional hallucinations and paroxysmal jerking of the extremities. L-alpha-methyldopa 500 mg b.i.d. (later reduced to 250 mg t.i.d.) was added to her regimen. Hallucinations and seizures stopped shortly. Over the course of approximately 1 year, the previous medications were discontinued without recurrence of psychotic and epileptic symptoms. Eventually, improved mental functions and behaviour enabled her transition from living in a licensed residential facility to sharing a private residence with a partner. VCFS is associated with haploinsufficiency of catecholamine-methyltransferase, leading to excessive extraneuronal catecholamine concentrations. Alpha-Methyldopa inhibits catecholamine neurotransmission in a variety of ways. It is possible that the drug compensated for genetically disturbed catecholamine transmission thus achieving beneficial effects in this case.


Assuntos
Anormalidades Múltiplas/genética , Agonistas alfa-Adrenérgicos/uso terapêutico , Anticonvulsivantes/uso terapêutico , Antipsicóticos/uso terapêutico , Anormalidades Craniofaciais/genética , Metildopa/uso terapêutico , Transtornos Psicóticos/tratamento farmacológico , Adulto , Feminino , Humanos , Fenótipo , Transtornos Psicóticos/genética , Convulsões/tratamento farmacológico , Convulsões/genética , Síndrome
15.
J Psychopharmacol ; 16(1): 57-64, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11949773

RESUMO

Emedastine is registered in its country of origin (Japan) as an antihistamine for the indication of seasonal allergic rhinitis. Further research on the drug's sedating properties was needed to secure its registration elsewhere. The present study was designed to compare the effects of emedastine 2 mg and 4 mg twice daily after single and repeated doses, on actual driving performance versus those of cetirizine 10 mg once daily and placebo; and to determine how repeated doses of each drug interact with alcohol to affect driving. Each treatment was administered for 5 days to 19 healthy volunteers (nine men and ten women, aged 21-45 years) according to a four-period double-blind cross-over design. Driving performance was measured in a standardized test between 3 and 4 h after administration of the morning dose on days 1, 4 and 5. Alcohol, sufficient for achieving a blood alcohol concentration of 0.05 g/dl was given before driving on day 5 of each period. Both emedastine doses similarly and significantly impaired driving in every test. The effects of cetirizine were less. They were significant over days 1, 4 and 5 combined, although not separately. Women were more impaired by both drugs. Alcohol increased driving impairment similarly in every condition. Subjects were only able to discriminate the sedating and impairing effects of the first dose of emedastine 4 mg from placebo. Emedastine, in oral doses of 2 mg and 4 mg twice daily, is sedating and impairs driving. The drug could therefore constitute a traffic hazard and its users should be warned accordingly.


Assuntos
Condução de Veículo , Benzimidazóis/efeitos adversos , Depressores do Sistema Nervoso Central/efeitos adversos , Cetirizina/efeitos adversos , Etanol/efeitos adversos , Antagonistas dos Receptores Histamínicos H1/efeitos adversos , Adulto , Afeto/efeitos dos fármacos , Atenção/efeitos dos fármacos , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Interações Medicamentosas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Desempenho Psicomotor/efeitos dos fármacos , Fases do Sono/efeitos dos fármacos
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