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1.
PLoS One ; 16(4): e0248473, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33793595

RESUMO

INTRODUCTION: As US Hispanic populations are at higher risk than non-Hispanics for cardiovascular disease and Type 2 diabetes targeted interventions are clearly needed. This paper presents the four years results of the Vida Sana Program (VSP), which was developed and is implemented by a small clinic serving mostly Spanish-speaking, limited literacy population. METHODS: The eight-week course of interactive two-hour sessions taught by Navegantes, bilingual/cultural community health workers, was delivered to participants with hypertension, or high lipids, BMI, waist circumference, glucose or hemoglobin A1C (A1C). Measures, collected by Navegantes and clinic nurses, included blood chemistries, blood pressure, anthropometry, and an assessment of healthy food knowledge. RESULTS: Most participants (67%) were female, Hispanic (95%), and all were 18 to 70 years of age. At baseline, close to half of participants were obese (48%), had high waist circumference (53%), or elevated A1C (52%), or fasting blood glucose (57%). About one third had high blood pressure (29%) or serum cholesterol (35%), and 22% scored low on the knowledge assessment. After the intervention, participants decreased in weight (-1.0 lb), BMI (-0.2 kg/m2), WC (-0.4 inches), and cholesterol (-3.5 mg/dl, all p<0.001). Systolic blood pressure decreased (-1.7 mm Hg, p<0.001), and the knowledge score increased (6.8 percent, p<0.001). DISCUSSION: VSP shows promising improvements in metabolic outcomes, similar to other programs with longer duration or higher intensity interventions. VSP demonstrates an important model for successful community-connected interventions.


Assuntos
Diabetes Mellitus Tipo 2/prevenção & controle , Promoção da Saúde , Hipertensão/prevenção & controle , Estilo de Vida , Síndrome Metabólica/prevenção & controle , Obesidade/prevenção & controle , Adolescente , Adulto , Idoso , Antropometria/métodos , Agentes Comunitários de Saúde , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Hispânico ou Latino , Humanos , Hipertensão/fisiopatologia , Masculino , Síndrome Metabólica/fisiopatologia , Pessoa de Meia-Idade , Obesidade/fisiopatologia , Educação de Pacientes como Assunto/métodos , Resultado do Tratamento , Adulto Jovem
2.
J Exp Biol ; 222(Pt 22)2019 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-31636156

RESUMO

Animals are able to assess the risk of predation and respond accordingly via behavioural and physiological changes. Web-building spiders are in the unique situation where they reside in the middle of their web and are therefore relatively exposed to predators. Thus, these spiders might moderate either their web-building behaviour or their behaviour on the web when exposed to the threat of predation. In this study, we experimentally explored how chemical cues from a predator influence foraging behaviour and metabolic rate in females of the orb-web spider Argiope keyserlingi We found that female spiders restricted their foraging time budget when exposed to the predator cues from a praying mantid: they responded 11% and 17% quicker to a vibratory stimulus compared with control and non-predator cues, respectively, and spent less time handling the prey. Moreover, spiders were less likely to rebuild the web under predator cues. Female A. keyserlingi exposed to the praying mantid cue significantly elevated their metabolic rate compared with the control group. Our findings revealed short-term modifications over the 2 week trials in foraging behaviour and the physiology of female spiders in response to predator cues. This study suggests that under predator cues the spiders move quicker and this could be facilitated by elevation in metabolic rate. Reduced foraging activity and less frequent web repair/rebuilding would also reduce the spiders' exposure to praying mantid predators.


Assuntos
Sinais (Psicologia) , Comportamento Predatório , Aranhas/fisiologia , Animais , Metabolismo Basal , Feminino , Mantódeos/química , Fatores de Tempo
3.
Naturwissenschaften ; 104(9-10): 75, 2017 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-28836048

RESUMO

Well-developed antennae are crucial for many insects, but especially for scramble competitors, who race to find their mates using female sex cues. In these systems, the ability of males to locate females quickly is thought to be under strong selection. A rarely tested assumption is that males with more sensory structures are able to locate females faster. In the present study, we used the false garden mantid Pseudomantis albofimbriata to investigate male antennal morphology and its effect on male efficiency in finding a mate. We used scanning electron microscopy to describe the major sensilla types and their arrangement along the length of male antennae. We also conducted field enclosure trials relating male antennal morphology to scramble competition in this system. We identified six different types of antennal sensilla (cheatic, trichoid, basiconic, grooved peg, ceolocapitular and campaniform) on male P. albofimbriata antennae. As expected, males who had more trichoid sensilla located females quicker than did males with fewer sensilla. Results of the current study suggest that antenna morphology plays a significant role in mate location and hence scramble competition in the P. albofimbriata mating system.


Assuntos
Mantódeos , Animais , Antenas de Artrópodes , Feminino , Jardins , Masculino , Microscopia Eletrônica de Varredura , Sensilas , Comportamento Social
4.
Proc Biol Sci ; 283(1833)2016 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-27358366

RESUMO

Models of the evolution of sexual cannibalism argue that males may offset the cost of cannibalism if components of the male body are directly allocated to the eggs that they fertilize. We tested this idea in the praying mantid Tenodera sinensis Males and females were fed differently radiolabelled crickets and allowed to mate. Half of the pairs progressed to sexual cannibalism and we prevented cannibalism in the other half. We assess the relative allocation of both male-derived somatic materials and ejaculate materials into the eggs and soma of the female. Our results show that male somatic investment contributes to production of offspring. The eggs and reproductive tissues of cannibalistic females contained significantly more male-derived amino acids than those of non-cannibalistic females, and there was an increase in the number of eggs produced subsequent to sexual cannibalism. Sexual cannibalism thus increases male material investment in offspring. We also show that males provide substantial investment via the ejaculate, with males passing about 25% of their radiolabelled amino acids to females via the ejaculate even in the absence of cannibalism.


Assuntos
Canibalismo , Mantódeos/fisiologia , Comportamento Sexual Animal , Animais , Feminino , Masculino , Reprodução
5.
PLoS One ; 10(9): e0137814, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26332736

RESUMO

[This corrects the article DOI: 10.1371/journal.pone.0124209.].

6.
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
7.
PLoS One ; 10(5): e0124209, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25970459

RESUMO

Strategic ejaculation is a behavioural strategy shown by many animals as a response to sperm competition and/or as a potential mechanism of cryptic male choice. Males invest more mating resources when the risk of sperm competition increases or they invest more in high quality females to maximize their reproductive output. We tested this hypothesis in the false garden mantid Pseudomantis albofimbriata, where females are capable of multiply mating and body condition is an indicator of potential reproductive fitness. We predicted male mantids would ejaculate strategically by allocating more sperm to high quality females. To determine if and how males alter their ejaculate in response to mate quality, we manipulated female food quantity so that females were either in good condition with many eggs (i.e. high quality) or poor condition with few eggs (i.e. low quality). Half of the females from each treatment were used in mating trials in which transferred sperm was counted before fertilisation occurred and the other half of females were used in mating trials where fertilisation occurred and ootheca mass and total eggs in the ootheca were recorded. Opposed to our predictions, the total number of sperm and the proportion of viable sperm transferred did not vary significantly between female treatments. Male reproductive success was entirely dependent on female quality/fecundity, rather than on the number of sperm transferred. These results suggest that female quality is not a major factor influencing postcopulatory male mating strategies in P. albofimbriata, and that sperm number has little effect on male reproductive success in a single mating scenario.


Assuntos
Ejaculação/fisiologia , Aptidão Genética/fisiologia , Mantódeos/fisiologia , Oócitos/fisiologia , Animais , Sobrevivência Celular , Tamanho da Ninhada/fisiologia , Feminino , Fertilização/fisiologia , Masculino , Oócitos/citologia , Oviposição/fisiologia , Análise do Sêmen , Comportamento Sexual Animal/fisiologia , Espermatozoides/citologia , Espermatozoides/fisiologia
8.
Proc Biol Sci ; 282(1800): 20141428, 2015 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-25520352

RESUMO

Animal communication theory holds that in order to be evolutionarily stable, signals must be honest on average, but significant dishonesty (i.e. deception) by a subset of the population may also evolve. A typical praying mantid mating system involves active mate searching by males, which is guided by airborne sex pheromones in most species for which mate-searching cues have been studied. The Femme Fatale hypothesis suggests that female mantids may be selected to exploit conspecific males as prey if they benefit nutritionally from cannibalism. Such a benefit exists in the false garden mantid Pseudomantis albofimbriata-females use the resources gained from male consumption to significantly increase their body condition and reproductive output. This study aimed to examine the potential for chemical deception among the subset of females most likely to benefit from cannibalism (poorly fed females). Females were placed into one of four feeding treatments ('Very Poor', 'Poor', 'Medium' and 'Good'), and males were given the opportunity to choose between visually obscured females in each of the treatments. Female body condition and fecundity varied linearly with food quantity; however, female attractiveness did not. That is, Very Poor females attracted significantly more males than any of the other female treatments, even though these females were in significantly poorer condition, less fecund (in this study) and more likely to cannibalise (in a previous study). In addition, there was a positive correlation between fecundity and attractiveness if Very Poor females were removed from the analysis, suggesting an inherently honest signalling system with a subset of dishonest individuals. This is the first empirical study to provide evidence of sexual deception via chemical cues, and the first to provide support for the Femme Fatale hypothesis.


Assuntos
Mantódeos/fisiologia , Preferência de Acasalamento Animal , Comunicação Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Canibalismo , Sinais (Psicologia) , Feminino , Fertilidade , Masculino , Atrativos Sexuais/fisiologia
9.
Insect Sci ; 21(2): 227-33, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23956112

RESUMO

Sexual size dimorphism (SSD) is widespread among diverse animal taxa and has attracted the attention of evolutionary biologists for over a century. SSD is likely to be adaptive and the result of divergent selection on different size optima for males and females, given their different roles in reproduction. The developmental trajectory leading to SSD may help us to understand how selection acts on male and female size. Here, we describe the growth and development of two Australian praying mantids, Pseudomantis albofimbriata and Hierodula majuscula including the number of moults, time to adulthood, size at each moult, and the degree of SSD. While both species exhibit the common pattern of female-biased SSD, the number of moults required for individuals to reach adulthood differed between males and females and between species. Despite their larger adult size, P. albofimbriata females require fewer moults and less time than males to reach adulthood, but are significantly larger than males from the second instar onwards. In contrast, H. majuscula males reached adulthood in fewer moults, and less time than females, however males and females did not differ in size until females went through their final moult into adulthood. H. majuscula also required more time and more moults to reach adulthood than P. albofimbriata. We discuss these different developmental pathways in light of the existing knowledge of reproductive biology for each species. We also suggest that these differences may relate to the different phenologies that occur in strongly seasonal temperate environments compared with those in the tropics. This study provides evidence that SSD can result from two different patterns of growth and development in closely related species.


Assuntos
Tamanho Corporal , Mantódeos/crescimento & desenvolvimento , Caracteres Sexuais , Animais , Austrália , Feminino , Masculino , Reprodução , Estações do Ano , Clima Tropical
10.
PLoS One ; 8(10): e78164, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24130901

RESUMO

Resource limitation during the juvenile stages frequently results in developmental delays and reduced size at maturity, and dietary restriction during adulthood can affect longevity and reproductive output. Variation in food intake can also result in alteration to the normal pattern of resource allocation among body parts or life-history stages. My primary aim in this study was to determine how varying juvenile and/or adult feeding regimes affect particular female and male traits in the sexually cannibalistic praying mantid Pseudomantis albofimbriata. Praying mantids are sit-and-wait predators whose resource intake can vary dramatically depending on environmental conditions within and across seasons, making them useful for studying the effects of feeding regime on various facets of reproductive fitness. In this study, there was a significant trend/difference in development and morphology for males and females as a result of juvenile feeding treatment, however, its effect on the fitness components measured for males was much greater than on those measured for females. Food-limited males were less likely to find a female during field enclosure experiments and smaller males were slower at finding a female in field-based experiments, providing some of the first empirical evidence of a large male size advantage for scrambling males. Only adult food limitation affected female fecundity, and the ability of a female to chemically attract males was also most notably affected by adult feeding regime (although juvenile food limitation did play a role). Furthermore, the significant difference/trend in all male traits and the lack of difference in male trait ratios between treatments suggests a proportional distribution of resources and, therefore, no trait conservation by food-limited males. This study provides evidence that males and females are under different selective pressures with respect to resource acquisition and is also one of very few to show an effect of juvenile food quantity on adult reproductive fitness in a hemimetabolous insect.


Assuntos
Mantódeos/fisiologia , Animais , Canibalismo , Ingestão de Alimentos , Feminino , Fertilidade , Masculino , Reprodução
11.
Anim Cogn ; 9(1): 47-54, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16160818

RESUMO

Most birds rely on imprinting and experience with conspecifics to learn species-specific recognition cues. Australian brush-turkeys (Alectura lathami) do not imprint and form no bonds with parents. They hatch asynchronously, disperse widely and meet juvenile conspecifics at an unpredictable age. Nevertheless, in captivity, hatchlings respond to other chicks. A recent study, which involved the use of robotic models, found that chicks prefer to approach robots that emit specific visual cues. Here, we evaluated their response to acoustic cues, which usually play an important role in avian social cognition. However, in simultaneous choice tests, neither 2-day-old nor 9-day-old chicks preferred the choice arm with playback of either chick or adult conspecific calls over the arm containing a silent loudspeaker. Chicks of both age classes, however, scanned their surroundings more during chick playback, and the response was thus consistent in younger and older chicks. We also presented the chicks with robotic models, either with or without playback of chick calls. They did not approach the calling robot more than they did the silent robot, indicating that the combination of visual and acoustic cues does not evoke a stronger response. These results will allow further comparison with species that face similar cognitive demands in the wild, such as brood parasites. Such a comparative approach, which is the focus of cognitive ecology, will enable us to further analyse the evolution and adaptive value of species recognition abilities.


Assuntos
Comunicação Animal , Galliformes/fisiologia , Comportamento Social , Animais , Austrália , Sinais (Psicologia) , Robótica , Especificidade da Espécie , Percepção Visual
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