Caloric reserves in natural populations of a blackfly, Simulium decorum (Diptera: Simuliidae), and a deerfly, Chrysops ater (Diptera: Tabanidae)

1984 ◽  
Vol 62 (12) ◽  
pp. 2589-2593
Author(s):  
Louis A. Magnarelli ◽  
John F. Burger
Keyword(s):  
New Hampshire ◽  
Early Adulthood ◽  
Natural Populations ◽  
Follicular Development ◽  
Chemical Test ◽  
Sucrose Solutions ◽  
Sodium Bichromate ◽  
Males And Females ◽  
Simulium Decorum ◽  
Blood Meals

Simulium decorum and Chrysops ater immatures were collected in northern New Hampshire during 1982 and were reared to adults in the laboratory to describe follicular development, to quantify total available caloric reserves, and to determine longevity. Females of both species produced eggs without blood meals and sucrose solutions during the first ovarian cycle. Differences in mean fecundity (mean range, 152–215) were noted for the Chrysops obtained at three sites below a trout-rearing pond. A chemical test consisting of a sulfuric acid solution of sodium bichromate was used to quantify caloric reserves in the newly emerged blackflies and deerflies. Available reserves for S. decorum females, ≤4 h or 24 h after eclosion, were about sevenfold greater than those of the males. There were no significant differences in available reserves for adult deerflies. Although males and females of both species utilized stored reserves for survival during early adulthood, sugars greatly enhanced longevity.

scholarly journals No sex differences in learning in wild bumblebees

2021 ◽  
Author(s):  
Felicity Muth ◽  
Amber D Tripodi ◽  
Rene Bonilla ◽  
James P Strange ◽  
Anne S Leonard
Keyword(s):  
Sex Differences ◽  
Associative Learning ◽  
Sierra Nevada ◽  
Comparative Cognition ◽  
Natural Populations ◽  
Interspecific Variation ◽  
Learning Task ◽  
Learning Ability ◽  
Learning Performance ◽  
Males And Females

Abstract Females and males often face different sources of selection, resulting in dimorphism in morphological, physiological, and even cognitive traits. Sex differences are often studied in respect to spatial cognition, yet the different ecological roles of males and females might shape cognition in multiple ways. For example, in dietary generalist bumblebees (Bombus), the ability to learn associations is critical to female workers, who face informationally rich foraging scenarios as they collect nectar and pollen from thousands of flowers over a period of weeks to months to feed the colony. While male bumblebees likely need to learn associations as well, they only forage for themselves while searching for potential mates. It is thus less clear whether foraging males would benefit from the same associative learning performance as foraging females. In this system, as in others, cognitive performance is typically studied in lab-reared animals under captive conditions, which may not be representative of patterns in the wild. In the first test of sex and species differences in cognition using wild bumblebees, we compared the performance of Bombus vancouverensis nearcticus (formerly bifarius) and Bombus vosnesenskii of both sexes on an associative learning task at Sierra Nevada (CA) field sites. Across both species, we found that males and females did not differ in their ability to learn, although males were slower to respond to the sucrose reward. These results offer the first evidence from natural populations that male bumblebees may be equally as able to learn associations as females, supporting findings from captive colonies of commercial bees. The observed interspecific variation in learning ability opens the door to using the Bombus system to test hypotheses about comparative cognition.

Longevity of Anopheles maculipennis race atroparvus, van Thiel, at controlled Temperature and Humidity after one Blood Meal

1939 ◽  
Vol 30 (3) ◽  
pp. 295-301 ◽  
Author(s):  
H. S. Leeson
Keyword(s):  
Blood Meal ◽  
Small Proportion ◽  
Feeding Period ◽  
Anopheles Maculipennis ◽  
Culex Fatigans ◽  
Temperature And Humidity ◽  
Males And Females ◽  
Blood Meals

From January to July 1938, experiments with Anopheles maculipennis race atroparvus, Van Thiel, were undertaken to discover whether humidity and the age at which the females fed influenced their longevity. It was found that they lived longer at higher than at lower humidities; that most of the females which fed did so in the first three days; that those which fed on the second day after emergence lived longer than those which fed at other ages; and that the feeding period was slightly extended in the later experiments, though only a small proportion lived long enough to take their first blood meals on the fourth and fifth days.Rather more than 50 per cent. of each batch of newly emerged adults were females.A large proportion of the deaths of unfed males and females occurred during the first three days, most of them on the second day; this mortality decreased in successive experiments.Culex fatigans, Wied., behaved similarly.

scholarly journals Population and reproductive traits of a freshwater amphipod (Crustacea, Peracarida, Hyalellidae) from northwest of the state of Rio Grande do Sul, Brazil

2020 ◽  
Vol 20 (2) ◽  
Author(s):  
Daniela da Silva Castiglioni ◽  
Marcio Limberger ◽  
Vanessa da Silva Castro ◽  
Francieli Ubessi
Keyword(s):  
No Reduction ◽  
Natural Populations ◽  
Reproductive Traits ◽  
Bimodal Distribution ◽  
Southern Brazil ◽  
Natural Pond ◽  
Males And Females ◽  
The Mean ◽  
Anthropic Influence ◽  
Almost All

Abstract The study of population and reproductive traits provides information about the ecological structure of natural populations. This study aimed to characterize dynamics and reproductive traits of Hyalella palmeirensis from a natural pond from southern Brazil. The amphipods were sampled monthly (August 2012 to July 2013) by a person with the aid of a hand net for 20 minutes. Ovigerous females and pre-copulatory pairs were individualized in the field. A total of 12,325 individuals were sampled, being 1,421 males, 6,983 females (including 215 ovigerous females) and 3,921 juveniles. Paired and unpaired males were significantly greater in size than females. There was a positive correlation between body size (CL) of paired males and females. Males and females showed bimodal distribution. Total sex ratio favored females, and these were more frequent in almost all months. Ovigerous females and precopulatory pairs were found throughout the year, but with high frequency in winter and autumn, respectively, characterizing a seasonal reproduction. Juveniles were sampled throughout the year, with greater intensity in the spring. The mean fecundity was 19.6 ± 4.34 eggs. No reduction in the number of eggs was observed during embryonic development. The results observed in H. palmeirensis demonstrate that this species has a population and reproductive dynamics very similar to other species of Hyalella already analyzed in southern Brazil. Moreover, it can be seen that although the H. palmeirensis occurs in an environment with anthropic influence (soy cultivation,) the population is managing to remain in the area, with reproduction and recruitment in most months of year.

Larval distribution and succession of outlet-breeding blackflies (Diptera: Simuliidae) in New Hampshire

1983 ◽  
Vol 61 (11) ◽  
pp. 2519-2533 ◽  
Author(s):  
Douglas J. Lake ◽  
John F. Burger
Keyword(s):  
North America ◽  
New Hampshire ◽  
Sibling Species ◽  
Stream Flow ◽  
Specific Site ◽  
Late Winter ◽  
Multiple Generations ◽  
Substrate Reduction ◽  
Larval Distribution ◽  
Simulium Decorum

Thirteen described species of outlet-breeding simuliids and five isomorphic sibling species of the Simulium venustum/verecundum complexes were collected in 1978 and 1979. Prosimulium fuscum, P. mixtum, Simulium aestivum, S. aureum, S. decorum; S. tuberosum, S. venustum (CC) and S. vernum were the most widely distributed species while S. aureum, S. decorum and S. venustum (CC) were the most abundant. Simulium decorum, S. tuberosum and S. venustum (AC(gB) and CC) were present at the same sites during both years while the remaining species varied in their occurrence at a specific site between the two years. Succession of Simulium spp. in late winter and spring was similar to that reported from other areas of northern North America. Most Simulium spp. studied were multivoltine while S. corbis, S. croxtoni and S. venustum (A/C) were univoltine. Simulium decorum had single or multiple generations, depending on the site. Larvae of S. venustum (A/C) and most species of the subgenus Eusimulium attached to trailing vegetation, while S. corbis, S. decorum, and S. tuberosum attached more frequently to submerged rocks and sticks. Prosimulium fontanum, S. gouldingi, S. venustum (CC and AC(gB)), and S. verecundum (A/C and ACD) did not demonstrate preference for a particular substrate. Reduction in stream flow affected the number of cohorts of S. aestivum and S. aureum and the number of generations per year of S. aureum and S. vernum.

Changes in health risk behaviors for males and females from early adolescence through early adulthood.

2013 ◽  
Vol 32 (6) ◽  
pp. 685-694 ◽  
Author(s):  
James R. Mahalik ◽  
Rebekah Levine Coley ◽  
Caitlin McPherran Lombardi ◽  
Alicia Doyle Lynch ◽  
Anna J. Markowitz ◽  
...  
Keyword(s):  
Health Risk ◽  
Risk Behaviors ◽  
Early Adolescence ◽  
Early Adulthood ◽  
Health Risk Behaviors ◽  
Males And Females

scholarly journals Anomalous colour in Neotropical mammals: a review with new records for Didelphis sp. (Didelphidae, Didelphimorphia) and Arctocephalus australis (Otariidae, Carnivora)

2013 ◽  
Vol 73 (1) ◽  
pp. 185-194 ◽  
Author(s):  
MSL. Abreu ◽  
R. Machado ◽  
F. Barbieri ◽  
NS. Freitas ◽  
LR. Oliveira
Keyword(s):  
New Records ◽  
Natural Populations ◽  
South American ◽  
Southern Brazil ◽  
Wild Populations ◽  
Terrestrial Mammals ◽  
Animal Survival ◽  
Fur Seal ◽  
Neotropical Mammals ◽  
Males And Females

Anomalous colourations occur in many tropical vertebrates. However, they are considered rare in wild populations, with very few records for the majority of animal taxa. We report two new cases of anomalous colouration in mammals. Additionally, we compiled all published cases about anomalous pigmentation registered in Neotropical mammals, throughout a comprehensive review of peer reviewed articles between 1950 and 2010. Every record was classified as albinism, leucism, piebaldism or eventually as undetermined pigmentation. As results, we report the new record of a leucistic specimen of opossum (Didelphis sp.) in southern Brazil, as well as a specimen of South American fur seal (Arctocephalus australis) with piebaldism in Uruguay. We also found 31 scientific articles resulting in 23 records of albinism, 12 of leucism, 71 of piebaldism and 92 records classified as undetermined pigmentation. Anomalous colouration is apparently rare in small terrestrial mammals, but it is much more common in cetaceans and michrochiropterans. Out of these 198 records, 149 occurred in cetaceans and 30 in bats. The results related to cetaceans suggest that males and females with anomolous pigmentation are reproductively successful and as a consequence their frequencies are becoming higher in natural populations. In bats, this result can be related to the fact these animals orient themselves primarily through echolocation, and their refuges provide protection against light and predation. It is possible that anomalous colouration occurs more frequently in other Neotropical mammal orders, which were not formally reported. Therefore, we encourage researchers to publish these events in order to better understand this phenomenon that has a significant influence on animal survival.

scholarly journals Sex differences in senescence: the role of intra-sexual competition in early adulthood

2015 ◽  
Vol 282 (1811) ◽  
pp. 20151086 ◽  
Author(s):  
Christopher Beirne ◽  
Richard Delahay ◽  
Andrew Young
Keyword(s):  
Sex Differences ◽  
Early Adulthood ◽  
Meles Meles ◽  
Reproductive Competition ◽  
Sexual Competition ◽  
Somatic Maintenance ◽  
Downstream Effects ◽  
Males And Females ◽  
European Badgers

Males and females frequently differ in their rates of ageing, but the origins of these differences are poorly understood. Sex differences in senescence have been hypothesized to arise, because investment in intra-sexual reproductive competition entails costs to somatic maintenance, leaving the sex that experiences stronger reproductive competition showing higher rates of senescence. However, evidence that sex differences in senescence are attributable to downstream effects of the intensity of intra-sexual reproductive competition experienced during the lifetime remains elusive. Here, we show using a 35 year study of wild European badgers ( Meles meles ), that (i) males show higher body mass senescence rates than females and (ii) this sex difference is largely attributable to sex-specific downstream effects of the intensity of intra-sexual competition experienced during early adulthood . Our findings provide rare support for the view that somatic maintenance costs arising from intra-sexual competition can cause both individual variation and sex differences in senescence.

scholarly journals Puberty Timing and Markers of Cardiovascular Structure and Function at 25 Years: A Prospective Cohort Study

2020 ◽  
Author(s):  
Gillian M. Maher ◽  
Lisa Ryan ◽  
Fergus P. McCarthy ◽  
Alun Hughes ◽  
Chloe Park ◽  
...  
Keyword(s):  
Cohort Study ◽  
Cardiovascular Risk ◽  
Early Adulthood ◽  
Left Ventricular ◽  
Structure And Function ◽  
Height Velocity ◽  
Cardiovascular Structure ◽  
Males And Females ◽  
One Year ◽  
And Function

AbstractImportanceWhether earlier onset of puberty is associated with higher cardiovascular risk in early adulthood is not well understood.ObjectiveTo examine the association between puberty timing and markers of cardiovascular structure and function at age 25 years.DesignProspective birth cohort study.SettingThe Southwest region of England.ParticipantsParticipants in the Avon Longitudinal Study of Parents and Children (ALSPAC), born between April 1, 1991, and December 31, 1992.ExposureAge at peak height velocity (aPHV), an objective and validated growth-based measure of puberty onset.Main Outcomes and MeasuresCardiovascular structure and function at age 25 years: carotid intima-media thickness (CIMT), left ventricular mass index (LVMI) and relative wall thickness (RWT), pulse wave velocity (PWV) and systolic blood pressure (SBP). Multiple imputation was used to impute missing data on covariates and outcomes. Linear regression was used to examine the association between aPHV and each measure of cardiac structure and function, adjusting for maternal age, gestational age, household social class, maternal education, mother’s partner’s education, breastfeeding, parity, birthweight, maternal body mass index, maternal marital status, maternal prenatal smoking status, and height and fat mass at age 9. All analyses were stratified by sex.ResultsA total of 2752-4571 participants were included in the imputed analyses. A one-year older aPHV was not strongly associated with markers of cardiac structure and function in males and females at 25 years and most results spanned the null value. In adjusted analyses a one-year older aPHV was associated with 0.003mm (95% Confidence Interval (CI): 0.00001, 0.006) and 0.0008mm (95% CI: −0.002, 0.003) higher CIMT; 0.02m/s (95% CI: −0.05, 0.09) and 0.02m/s (95% CI: −0.04, 0.09) higher PWV; and 0.003mmHg (95% CI: −0.60, 0.60) and 0.13mmHg (95% CI: −0.44, 0.70) higher SBP, among males and females respectively. A one-year older aPHV was associated with −0.55g/m2.7 (95% CI: −0.03, −1.08) and −0.89g/m2.7 (95% CI: −0.45, −1.34) lower LVMI and −0.001 (95% CI: −0.006, 0.002) and −0.002 (95% CI: −0.006, 0.002) lower RWT among males and females.Conclusions and RelevanceEarlier puberty is unlikely to have a major impact on pre-clinical cardiovascular risk in early adulthood.Key PointsQuestionIs puberty timing associated with cardiovascular structure and function at age 25 years?FindingsAdjusted estimates from this prospective birth cohort study suggest no strong evidence of association between age at puberty (measured using age at peak height velocity) and carotid intima-media thickness (CIMT), left ventricular mass index (LVMI), and relative wall thickness (RWT), pulse wave velocity (PWV), and systolic blood pressure (SBP) at age 25 years among males and females, with results spanning the null in all but LVMI.MeaningEarlier puberty is unlikely to have a major impact on pre-clinical cardiovascular risk in early adulthood.

scholarly journals 1280Natural history, developmental trajectories, and determinants of eczema from infancy to 26 years of age

2021 ◽  
Vol 50 (Supplement_1) ◽  
Author(s):  
Ali Ziyab ◽  
Nandini Mukherjee ◽  
Hasan Arshad ◽  
Wilfried Karmaus
Keyword(s):  
Risk Factors ◽  
Early Onset ◽  
Late Onset ◽  
Developmental Trajectories ◽  
Early Adulthood ◽  
Clinical Criteria ◽  
Adjusted Risk ◽  
Disease Patterns ◽  
Males And Females ◽  
Semiparametric Mixture Models

Abstract Background Eczema is a common inflammatory skin disease with varying developmental trajectories/patterns. This study sought to investigate eczema development from infancy to early adulthood by identifying distinct developmental trajectories that describe disease patterns over time and evaluate the role of early life risk factors. Methods The Isle of Wight Birth Cohort (n = 1456) was prospectively assessed at birth, 1, 2, 4, 10, 18, and 26 years. At each assessment, eczema was ascertained based on established clinical criteria. Developmental trajectories of eczema between 1-or-2 and 26 years were identified separately for males and females by applying semiparametric mixture models. Associations were assessed by applying a modified Poisson regression to estimate adjusted risk ratios (aRR) and 95% confidence intervals (CI). Results In both males and females, the following eczema trajectories were identified: unaffected/transient (77.7% vs. 73.0%), mid-onset late-resolving (7.8% vs. 4.4%), late-onset (5.2% vs. 9.5%), and early-onset persistent (9.3% vs. 5.4%). In females, an additional trajectory was identified: early-onset early-resolving (7.7%). Among males, filaggrin gene (FLG) variants (aRR = 2.45, 95% CI: 1.34-4.46) and paternal eczema (2.66, 1.39-5.08) were associated with the early-onset persistent trajectory. Among females, maternal eczema (2.84, 1.42-5.70) and high birthweight (2.25, 1.08-4.69) were associated with the early-onset persistent trajectory. Conclusions Four and five trajectories represented eczema development among males and females, respectively, with different predisposing risk factors. Key messages Males and females may experience a different course of eczema and also sex-specific risk factors.

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