Male mate-searching strategies and female cues: how do male guppies find receptive females?

Locating potential mates is critical to mating. We studied males’ association with females and mate-searching patterns in the guppy, Poecilia reticulata, a promiscuous live-bearer. In the field, we examined whether male guppies respond differently to a shoal of conspecific fish based on the members of the shoal. We found that more males were attracted to shoals that contained receptive females than to shoals of nonreceptive females or males. We also conducted laboratory experiments to investigate how males use olfactory cues of nonreceptive and receptive females to search for and associate with females. We gave males the option to associate with nonreceptive females when olfactory cues of receptive or nonreceptive females were present and absent, and when olfactory cues were presented alone. Males associated with females most strongly when both cues were presented simultaneously, but when cues were presented separately males’ association with females differed with respect to the olfactory cues that were added. Males associated with females equally with visual and olfactory cues presented separately when the odour cues were from receptive females. However, when the odour cues were from nonreceptive females, males associated with females less with olfactory than visual cues. Searching activity increased when males had access only to olfactory cues. Taken together these results suggest that olfactory cues influence males’ association with females and searching behaviour, and these changes in behaviour are likely to maximize a male’s opportunity to encounter receptive females.

Investigating the female profile of autism

An investigation into the hypothesis that females with high functioning autism present in a way that is not congruent with our current understanding of autism, as our current understanding is largely based on a male profile of autism. Autistic females were found to present differently socially, emotionally and behaviourally from autistic males.

Cross-sectional geometry of weight-bearing tibia in female athletes subjected to different exercise loadings

Summary The association of long-termsport-specific exercise loading with cross-sectional geometry of the weight-bearing tibia was evaluated among 204 female athletes representing five different exercise loadings and 50 referents. All exercises involving ground impacts (e.g., endurance running, ball games, jumping) were associated with thicker cortex at the distal and diaphyseal sites of the tibia and also with large diaphyseal cross-section, whereas the high-magnitude (powerlifting) and non-impact (swimming) exercises were not. Introduction Bones adapt to the specific loading to which they are habitually subjected. In this cross-sectional study, the association of long-term sport-specific exercise loading with the geometry of the weight-bearing tibia was evaluated among premenopausal female athletes representing 11 different sports.

Methods A total of 204 athletes were divided into five exercise loading groups, and the respective peripheral quantitative computed tomographic data were compared to data obtained from 50 physically active, non-athletic referents. Analysis of covariance was used to estimate the between-group differences.

Results At the distal tibia, the high-impact, odd-impact, and repetitive low-impact exercise loading groups had ~30% to 50% (p<0.05) greater cortical area (CoA) than the referents. At the tibial shaft, these three impact groups had ~15% to 20% (p<0.05) greater total area (ToA) and ~15% to 30% (p<0.05) greater CoA. By contrast, both the high-magnitude and repetitive non-impact groups had similar ToA and CoA values to the reference group at both tibial sites.

Conclusions High-impact, odd-impact, and repetitive lowimpact exercise loadings were associated with thicker cortex at the distal tibia. At the tibial shaft, impact loading was not only associated with thicker cortex, but also a larger cross-sectional area. High-magnitude exercise loading did not show such associations at either site but was comparable to repetitive non-impact loading and reference data. Collectively, the relevance of high strain rate together with moderate-to-high strain magnitude as major determinants of osteogenic loading of the weight-bearing tibia is implicated.

Direction-specific diaphyseal geometry and mineral mass distribution of tibia and fibula: A pQCT study of female athletes representing different exercise loading types

Bones adapt to prevalent loading, which comprises mainly forces caused by muscle contractions. Therefore, we hypothesized that similar associations would be observed between neuromuscular performance and rigidity of bones located in the same body segment. These associations were assessed among 221 premenopausal women representing athletes in high-impact, odd-impact, highmagnitude, repetitive low-impact, and repetitive nonimpact sports and physically active referents aged 17–40 years. The whole group mean age and body mass were 23 (5) and 63 (9) kg, respectively. Bone cross sections at the tibial and fibular mid-diaphysis were assessed with peripheral quantitative computed tomography (pQCT). Density-weighted polar section modulus (SSI) and minimal and maximal crosssectional moments of inertia (Imin, Imax) were analyzed. Bone morphology was described as the Imax/Imin ratio. Neuromuscular performance was assessed by maximal power during countermovement jump (CMJ). Tibial SSI was 31% higher in the high-impact, 19% in the odd-impact, and 30% in the repetitive low-impact groups compared with the reference group (P\0.005). Only the high-impact group differed from the referents in fibular SSI (17%, P\0.005). Tibial morphology differed between groups (P = 0.001), but fibular morphology did not (P = 0.247). The bone-bygroup interaction was highly significant (P\0.001). After controlling for height, weight, and age, the CMJ peak power correlated moderately with tibial SSI (r = 0.31, P\0.001) but not with fibular SSI (r = 0.069, P = 0.313). In conclusion, observed differences in the association between neuromuscular performance and tibial and fibular traits suggest
that the tibia and fibula experience different loading

Obstacles in the optimization of bone health outcomes in the female athlete triad

Maintaining low body weight for the sake of performance and aesthetic purposes is a common feature among young girls and women who exercise on a regular basis, including elite, college and high-school athletes, members of fitness centres, and recreational exercisers. High energy expenditure without adequate compensation in energy intake leads to an energy deficiency, which may ultimately affect reproductive function and bone health. The combination of low energy availability, menstrual disturbances and low bone mineral density is referred to as the ‘female athlete triad’. Not all athletes seek medical assistance in response to the absence of menstruation for 3 or more months as some believe that long-term amenorrhoea is not harmful. Indeed, many women may not seek medical attention until they sustain a stress fracture.
This review investigates current issues, controversies and strategies in the clinical management of bone health concerns related to the female athlete triad. Current recommendations focus on either increasing energy intake or decreasing energy expenditure, as this approach remains the most efficient strategy to prevent further bone health complications. However, convincing the athlete to increase energy availability can be extremely challenging.
Oral contraceptive therapy seems to be a common strategy chosen by many physicians to address bone health issues in young women with amenorrhoea, although there is little evidence that this strategy improves bone mineral density in this population. Assessment of bone health itself is difficult due to the limitations of dual-energy X-ray absorptiometry (DXA) to estimate bone strength. Understanding how bone strength is affected by low energy availability, weight gain and resumption of menses requires further investigations using 3-dimensional bone imaging techniques in order to improve the clinical management of the female athlete triad.

Socio-cultural influences on eating practices among female adolescents in Fiji

This thesis examined the sociocultural influences on food and eating practices for both Indigenous-Fijian and Indo-Fijian female adolescents. Findings confirmed the prevalence of traditional customs related to feasting and fasting practices. Weight-change behaviours related to food practices were predicted largely by family and religious influences.

Finding footy : female fan socialization and Australian rules football

The question of how, irrespective of gender, a person becomes a sports fan has been absent in sociological studies of sports supporters. Distinct from other studies of sport spectatorship that focus on the practices of already existing (and overwhelmingly male) fans, our research is the first to consider how women become supporters, and in doing so, it begins to redress the significant under-representation of women in sports fan research. From interviews with female supporters of the Australian Football League (AFL), this article identifies and critically assesses the modes by which women come to support sport. We propose four categories to explain the different ways women accomplish fandom, focusing on the importance of strong social ties and doxic actions in this process. The events, experiences and social relations that inform women's first encounters with AFL offers a template for the wider consideration of women as social agents in the sporting landscape.

An exploratory qualitative study of the self-reported impact of female-perpetrated childhood sexual abuse

The limited findings on the impact of female-perpetrated sexual abuse of children are often contradictory, particularly in relation to males. In this exploratory qualitative study, a sample of nine men and five women who reported that they had been sexually abused by women in their childhood were recruited from the general community. They completed a questionnaire that asked them to describe various aspects of their abuse experiences and the perceived consequences. For both men and women, the abuse was associated with negative outcomes across a range of functional areas in both childhood and adulthood. Many impacts were similar to those reported by victims of male-perpetrated sexual abuse. It is argued that the consequences of female-perpetrated child sexual abuse are serious, and further research is required to bring these issues to the awareness of both the public and professionals working in the field of child protection and counseling.

Chromatic interaction between egg pigmentation and skin chromatophores in the nuptial coloration of female two-spotted gobies

In two-spotted gobies (Gobiusculus flavescens Fabricius 1779), females develop an orange belly as they approach sexual maturity. Bright belly coloration is preferred by males and has been suggested to act as a female ornament. This coloration is unusual in that it originates partly from pigmentation of the abdominal skin but also from strongly pigmented gonads directly visible through the skin. In addition, females have been observed to temporarily become more colourful during courtship and competition. To understand how gonad and skin pigmentation interact in this nuptial coloration, the potential for colour modification via regulation of skin chromatophores was investigated. Noradrenaline caused aggregation of chromatophore pigment and was used to experimentally reduce the contribution of skin chromatophores to the nuptial coloration. Chromatophore pigment aggregation caused bellies to become less colourful and abdominal skin biopsies to become less colourful and more transparent. There was a strong positive relationship between belly coloration and the coloration of the underlying gonads. This shows that belly coloration honestly reflects egg pigmentation, mainly because the transparency of the abdominal skin allows other fish to see the gonads directly. Interestingly, when noradrenaline caused pigment to aggregate and thereby increased the transparency of the skin, the relationship between belly and gonad coloration weakened. We conclude that female G. flavescens have a potential to use skin chromatophores to rapidly alter their nuptial coloration, thereby affecting the efficacy with which information about gonad coloration is conveyed.

Temporal variability in a multicomponent trait : nuptial coloration of female two-spotted gobies

Animals that breed more than once may face different environmental and physiological conditions at each reproductive event. Costs and benefits of sexual ornaments could therefore vary both within and between breeding seasons. Despite this, the ornaments are often assumed to be fixed, and temporal changes in ornamentation have rarely been investigated. Female two-spotted gobies (Gobiusculus flavescens) have colorful orange bellies when sexually mature and nest-holding males prefer females with more colorful bellies. This nuptial coloration is caused both by the carotenoids-rich gonads being directly visible through the skin and by the chromatophore pigmentation of the abdominal skin. Toward the end of the breeding season, males become rare and females become the more competitive sex. We show that female ornamentation of G. flavescens is a complex multicomponent trait and that the separate components, as well as their interactions, are variable. As gonads matured, they became more colorful while the abdominal skin became more transparent, causing more intense belly coloration in sexually mature females. However, coloration varied greatly also among fully mature females, suggesting that it may not only be a signal of readiness to spawn. Indeed, belly coloration predicted gonad carotenoid concentration, but there were several important seasonal differences in color expression. Females sampled toward the end of the breeding season were more colorful. This was due to seasonal increases in both gonad carotenoid concentration and skin coloration. Thus, at a time when competition over males is stronger and the terminal reproductive event approaches, females appear to invest more in signaling.

Does female nuptial coloration reflect egg carotenoids and clutch quality in the Two-Spotted Goby (Gobiusculus flavescens, Gobiidae)?

Summary

1 - Carotenoid-based ornamentation has often been suggested to signal mate quality, and species with such ornaments have frequently been used in studies of sexual selection.

2 - Female Gobiusculus flavescens (Two-Spotted Goby) develop colourful orange bellies during the breeding season. Belly coloration varies among mature females, and previous work has shown that nest-holding males prefer females with more colourful bellies. Because males invest heavily in offspring during incubation, the evolution of this preference can be explained if colourful females provide males with eggs of higher quality.

3 - We tested this hypothesis by allowing males to spawn with ‘colourful’ and ‘drab’ females and comparing parameters including egg carotenoid concentration, clutch size, hatchability and larval viability between groups. We also investigated relationships between egg carotenoid concentration and clutch quality parameters.

4 - Eggs from colourful females had significantly higher concentrations of total carotenoids than drab females, and photographically quantified belly coloration was a good predictor of egg carotenoid concentration.

5 - Colourful females produced slightly larger clutches, but female belly coloration was not related to any measure of clutch quality. In addition, there were no significant relationships between egg carotenoids and clutch quality. Females with high levels of egg carotenoids spawned slightly earlier, however, possibly because they were more ready to spawn or because of male mate choice.

6 - Our results call into question the generality of a causal link between egg carotenoids and offspring quality.

Chemical immobilization of adult female Weddell seals with tiletamine and zolazepam: effects of age, condition and stage of lactation

Background

Chemical immobilization of Weddell seals (Leptonychotes weddellii) has previously been, for the most part, problematic and this has been mainly attributed to the type of immobilizing agent used. In addition to individual sensitivity, physiological status may play an important role. We investigated the use of the intravenous administration of a 1:1 mixture of tiletamine and zolazepam (Telazol®) to immobilize adult females at different points during a physiologically demanding 5–6 week lactation period. We also compared performance between IV and IM injection of the same mixture.
Results

The tiletamine:zolazepam mixture administered intravenously was an effective method for immobilization with no fatalities or pronounced apnoeas in 106 procedures; however, there was a 25 % (one animal in four) mortality rate with intramuscular administration. Induction time was slightly longer for females at the end of lactation (54.9 ± 2.3 seconds) than at post-parturition (48.2 ± 2.9 seconds). In addition, the number of previous captures had a positive effect on induction time. There was no evidence for effects due to age, condition (total body lipid), stage of lactation or number of captures on recovery time.
Conclusion

We suggest that intravenous administration of tiletamine and zolazepam is an effective and safe immobilizing agent for female Weddell seals. Although individual traits could not explain variation in recovery time, we suggest careful monitoring of recovery times during longitudinal studies (> 2 captures). We show that physiological pressures do not substantially affect response to chemical immobilization with this mixture; however, consideration must be taken for differences that may exist for immobilization of adult males and juveniles. Nevertheless, we recommend a mass-specific dose of 0.50 – 0.65 mg/kg for future procedures with adult female Weddell seals and a starting dose of 0.50 mg/kg for other age classes and other phocid seals.