Male Guarding Research Articles

Unraveling mate choice evolution through indirect genetic effects

Abstract Attractiveness is not solely determined by a single sexual trait but rather by a combination of traits. Because the response of the chooser is based on the combination of sexual traits in the courter, variation in the chooser’s responses that are attributable to the opposite-sex courter genotypes (i.e., the indirect genetic effects [IGEs] on chooser response) can reflect genetic variation in overall attractiveness. This genetic variation can be associated with the genetic basis of other traits in both the chooser and the courter. Investigating this complex genetic architecture, including IGEs, can enhance our understanding of the evolution of mate choice. In the present study on the field cricket Gryllus bimaculatus, we estimated (1) genetic variation in overall attractiveness and (2) genetic correlations between overall attractiveness and other pre- and postcopulatory traits (e.g., male latency to sing, female latency to mount, male guarding intensity, male and female body mass, male mandible size, and testis size) within and between sexes. We revealed a genetic basis for attractiveness in both males and females. Furthermore, a genetic variance associated with female attractiveness was correlated with a genetic variance underlying larger male testes. Our findings imply that males that mate with attractive females can produce offspring that are successful in terms of precopulatory sexual selection (daughters who are attractive) and postcopulatory sexual selection (sons with an advantage in sperm competition), potentially leading to runaway sexual selection. Our study exemplifies how the incorporation of the IGE framework provides novel insights into the evolution of mate choice.

Reproductive behavior of Erythrodiplax abjecta (Rambur, 1842) from Andean Mountains

Research about the behavior of Neotropical species is crucial to understand how the rapid environmental changes in the Neotropics affect the reproduction of various organisms. The reproductive behavior of insects in tropical ecosystems, such as those belonging to the order Odonata, is as yet scarcely known. In this article, the reproductive behavior of Erythrodiplax abjecta is described from several localities in the Colombian Andean Mountains. Playing out between 10:00 and 14:30 h, male individuals of this species may exhibit either territorial or satellite behavior. Sexually mature males and females engage in tandem and copulation behaviors, which are brief and may occur either perched or in flight. Females of E. abjecta oviposit directly in the water at various times, alternating with periods of rest. During oviposition, males stand guard over females, perched or hovering, in a quest to protect them against other males. Conspecific males have been observed to engage in sieges of perching or ovipositing females, as well as mating pairs. Following a siege, either the female or the original pair flees, or the besieging male will succeed in outcompeting the original male, take the female in tandem, copulate with her, and then guard her while she oviposits. If the female flees, she may perch elsewhere, continue ovipositing, or may be taken by another male. The intense male guarding behavior during oviposition could represent an adaptation to temporarily high male densities at oviposition sites and a high level of competition during the short period in which active copulation takes place.

Male guarding behavior and brood predators of invasive Bluegill in a Japanese lake

AbstractObjectiveThe Bluegill Lepomis macrochirus, which utilizes colony spawning, has been introduced globally, and in Japan it is considered one of the worst invasive species. However, a detailed examination of the factors driving male guarding behavior and brood predation in the invaded habitat is lacking. The removal of guarding males, a common management technique in Japan, is thought to be effective in controlling Bluegill. However, the colony spawning strategy may influence the effectiveness of selective male removal through brood protection from neighbor males.MethodsBluegill spawning was studied in Lake Nojiri, Nagano, Japan, using underwater video recording and experimental removal of guarding males.ResultBluegill were found spawning in shallow habitat during June–July, and nests were constructed in loosely aggregated colonies, with many solitary nests. Males utilized a variety of guarding behaviors, such as rim circling and predator chases, as well as paternal investment behaviors, such as tail fanning. Males that preyed upon their own eggs defended their nests less aggressively and invested less time in nourishing behaviors. Removal of guarding males revealed that brood predators were primarily conspecific Bluegill, but other fishes, such as invasive Smallmouth Bass Micropterus dolomieu and Largemouth Bass M. nigricans as well as native Japanese Dace Pseudaspius hakonensis, preyed on broods.ConclusionIn concurrence with the colony spawning theory, nests that were located closer to other nests with active guarding males experienced decreased brood predation and increased predator arrival time after male removal. In addition, nests where males had been guarding more aggressively prior to removal experienced reduced brood predation after male removal. These results provide insights into the factors driving male guarding behavior and brood predation of colony‐spawning Bluegill in an invasive habitat and indicate that the removal of guarding males—a common management strategy in Japan—may have reduced effectiveness due to colony spawning.

Pregnant Prisoners in Shackles

Pregnant Prisoners in Shackles

Association between Diet, Physical Activity and Nutritional Status of Male Border Guard Officers.

The main factors that determine the effectiveness and reliability of duties and tasks performed by border guard officers, are very good health and maintaining a high level of psychophysical fitness that depend mainly on adequate diet and physical activity and thus, nutritional status. The aim of the study was to verify the correlations between dietary habits, physical activity level and selected nutritional status indicators. One hundred and sixty-nine male border guard officers participated in the study. A 61-item food frequency questionnaire (FFQ) was used to assess dietary habits and a long-form International Physical Activity Questionnaire (IPAQ) was used to assess physical activity. Fat mass was determined by bioelectrical impedance analysis (BIA) and bone calcification was assessed by the dual energy X-ray absorptiometry (DXA). Many correlations between dietary habits, as well as the physical activity of officers and body mass index (BMI), fat mass index (FMI) and visceral fat level (VFL) were found, while bone mineral density (BMD T-score) negatively correlated only with two food groups and 6 out of 61 products but did not correlate with physical activity. The results also confirmed many poor dietary habits and abnormalities in nutritional status. Thus, there is a need for nutritional education and further monitoring of health-related behaviors, as well as monitoring the nutritional status of border guard officers.

Spawning season and nest guarding behavior of invasive smallmouth bass (Micropterus dolomieu) in a Japanese Lake

AbstractSpawning of invasive smallmouth bass (Micropterus dolomieu) was studied in 2020 and 2021, in Lake Nojiri, Nagano, Japan. Male smallmouth bass began nest construction once water temperatures reached 14°C, and eggs progressed to fry dispersal in approximately 2 weeks. The main spawning season was in late May through early June, with a smaller second peak of nests in late June through early July. Nests were constructed primarily under dock cover, and nest size and depth were positively correlated with male body size. Of the nests that received eggs, nearly all progressed successfully to fry dispersal. Time lapse videos of male guarding behavior revealed that as nests progressed, males rotated less and were suspended off the bottom substrate. Similarly, the presence of egg predators was determined by experimental removal of guarding males. Freshwater gobies (Rhinogobius kurodai) were the only egg predators observed and arrived on all nests in the egg stage. However, only a handful of gobies visited each nest, the total number of eggs predated was low, and eggs or alevins in the progressed stage were rarely predated. These results indicate that in Lake Nojiri, smallmouth bass spawning is highly successful and egg predators appear to have minimal effect on egg survival. The stable smallmouth bass fishery without stocking at this lake is likely a product of these favorable spawning conditions. The lack of native egg predators may also be a driving factor in the continued spread of smallmouth bass throughout Japan.

Investigation of presenteeism, physical function, and exercise habits in workers with CKD: three case reports with literature review

Management of presenteeism in the context of chronic kidney disease (CKD) is essential for disease management, ensuring the workforce’s availability, and reducing health-related costs. The purpose of this case study was to investigate presenteeism, physical function, and exercise habits in three working patients with CKD and discuss their effects. Case 1 was a 71-year-old male security guard; Case 2 was a 72-year-old male agricultural worker; and Case 3 was an 83-year-old male civil engineering employee. Presenteeism was measured using the work functioning impairment scale (WFun), and physical function was measured using grip strength, skeletal muscle mass index, 10 m walk test, short physical performance battery, and exercise habits. The WFun assessment showed that only Case 3 had moderate presenteeism, and the barrier to employment was fatigue. Each value of physical function was higher than the reference value, but Case 3 had the lowest physical function values. All three patients had no exercise habits and were in the interest stage of behavior change. This case report indicates the existence of workers with CKD who need care for presenteeism, even if they have no problems with physical function or activities of daily living. To ensure work productivity in workers with CKD, clinicians may need to evaluate presenteeism, physical function, and exercise habits in addition to popular treatment and care.

Physical and physiological demands according to gender, playing positions, and match outcomes in youth basketball players.

This study aimed to compare physical and physiological demands in youth basketball players according to gender, playing positions, and match outcomes. 64 players (32 female and 32 male) from eight youth sub-elite basketball teams were monitored using an Ultra-Wide Band system and inertial measurement unit in three consecutive matches. The results showed some significant differences, although with magnitudes qualified as small. When the teams won, the guards covered a greater distance at 0-6 km/h than when they lost. When teams lost, the centers covered more distance at 12-18 km/h and 18-21 km/h. The winning female teams presented a lower maximal heart rate (HRmax) compared to the losing teams. The forwards of the winning teams performed greater efforts at 70-80% HRmax, while the forwards of losing teams performed more efforts at 90-95% HRmax. The greatest number of accelerations and decelerations were performed by the female guards and the male forwards. The number of jumps was higher in the male guards and forwards than in the female ones. HRmax was higher in the forwards of the female teams. Efforts at 80%-90% HRmax were higher in male centers. When the female teams won, they had a lower HRmax than when they lost. When efforts exceed 90% of HRmax the teams lost. In conclusion, despite the differences found, the effect of these contextual variables on physical and physiological demands is unclear. Nevertheless, knowing the game's requirements can help the design of training that enhances the performance of youth basketball players

Nonmating behavioural differences between male tactics in the invasive round goby

Alternative reproductive tactics (ARTs) exist when individuals of one sex (usually males) adopt different strategies to achieve reproductive success. Although it is well known that the males adopting the different tactics often vary in their morphological, physiological and mating-based behavioural traits, what is not well understood is whether variation also exists in their behaviour outside the mating context. Here, we used the round goby, Neogobius melanostomus , a globally prolific invasive species where males exhibit ARTs, to address this knowledge gap. The nonmating behaviour of sneaker and guarder males were compared for differences in boldness, exploration, activity, aggression, sociality and dispersal. We found that sneaker males were more active, explorative and bold, as well as less aggressive compared to guarder males. Additionally, in an exploratory analysis, we found that while many behavioural traits were positively correlated in guarder males, few were correlated in sneaker males, suggesting that sneaker males might be more behaviourally plastic. The results of this study help expand our knowledge of the many ways that alternative reproductive tactics may differ from each other, particularly in nonmating contexts. • Round goby guarder and sneaker males had vastly different morphologies. • Sneaker males were more bold, explorative and active. • Guarder males were more aggressive. • There were no differences in sociality or dispersal tendency between tactics. • Many behavioural traits were correlated in guarder males but not in sneaker males.

Getting Ready for Continence Certification: Assessing and Managing Stress Incontinence.

Getting Ready for Continence Certification: Assessing and Managing Stress Incontinence.

Mate-guarding duration is mainly influenced by the risk of sperm competition and not by female quality in a golden orb-weaver spider.

Males are expected to mate with as many females as possible, but can maximize their reproductive success through strategic mating decisions. For instance, males can increase their own fitness by mating with high quality females that produce more offspring. Additionally, males can adjust mating effort based on the relative distribution of females and male competitors. To test factors that influence male mate choice, we assessed male mating decisions in the golden silk orb-weaver spider, Trichonephila clavipes (Nephilidae), a species in which females are polyandrous, males guard females before and after copulation occurs and large males are the most successful at guarding mates. We tested the hypothesis that males spend more time guarding high quality females that are spatially isolated, and when the risk of sperm competition is higher. We also hypothesized that this effect increases with male body size. We assessed solitary and aggregated female webs in the field and quantified female quality (i.e., female body condition), male size (i.e., male body size), the risk of sperm competition (i.e., number of males in each female web), and mate-guarding duration (i.e., number of days each male spent in each web). We found that mate-guarding behaviour is largely influenced by the presence of male competitors. In addition, male body size seems to moderately influence male guarding decisions, with larger males guarding for a longer time. Finally, female body condition and type of web (i.e., solitary or aggregated) seem to play small roles in mate-guarding behaviour. As mate-guarding duration increased by 0.718 day per each additional male competitor in the web, and guarding behaviour prevents males from seeking additional mates, it seems that guarding females can be considerably costly. We conclude that failing to guard a sexual partner promotes high costs derived from sperm competition, and a male cannot recover his relative loss in fertilization success by seeking and fertilizing more females. In addition, the search for more sexual partners can be constrained by possible high costs imposed by weight loss and fights against other males, which may explain why the type of web only moderately influenced male mate choice. Following the same rationale, if high-quality females are not easy to find and/or mating with a high-quality female demands much effort, males may search females and guard them regardless of female quality. In conclusion, the factor that most influences male mate-guarding behaviour among T. clavipes in the field is the risk of sperm competition.

Tactic-specific antimicrobial activity suggests a parental care function for accessory glands in a marine toadfish.

Males of some species possess extra reproductive organs called accessory glands which are outgrowths of the testes or sperm duct. These organs have a well-established role in reproduction; however, they also appear to have other important functions that are less understood. Here, we investigate the function of the highly complex accessory glands of a marine toadfish, Porichthys notatus, a fish with two reproductive male types: large care-providing 'guarder' males and small non-caring 'sneaker' males. While both male types have accessory glands, guarder male accessory glands are much larger relative to their body size. We show that accessory gland fluids strongly inhibit the growth of bacterial genera associated with unhealthy eggs and have no effect on the growth of strains isolated from healthy eggs. This antibacterial effect was particularly pronounced for extracts from guarder males. Furthermore, we demonstrate that both healthy and unhealthy plainfin midshipman eggs have diverse but distinct microbial communities that differ in their composition and abundance. The highly specific inhibitory capacity of accessory gland fluid on bacteria from unhealthy eggs was robust across a wide range of ecologically relevant temperatures and salinities. Collectively, these ecological and molecular observations suggest a care function for the accessory gland mediated by antimicrobial agents.

Motor nerve conduction velocity in median nerve: An observational study in adult healthy males with intact palmaris longus for normative reference value

Background: Pure motor nerve lesions are difficult to diagnose, as they usually exist with a syndrome complex. Their clinical manifestation is vague but electrodiagnosis is an efficient tool. Nerve conduction velocity (NCV) is an efficient neurophysiological investigation to examine and report nerve integrity. Aims and Objectives: The present cross-sectional study aims to develop normative electrophysiological reference values of median motor NCV among normative subjects with the presence of intact palmaris longus tendon (PLT). Materials and Methods: Motor nerve conduction studies (NCSs) of the median nerve were conducted in the upper limbs of 101 healthy security male guards, the recruits were having age group between 22 and 50 years, with intact and palpable PLT might influence the median nerve’s motor NCV around the wrist. The parameters of NCSs, such as amplitude, latency, and conduction speed of both hands, were recorded and analyzed. Results: Physiological profile parameters were given as mean ± SD. The mean values for age (28.77 ± 5.14 years), weight (70.53 ± 11.28 kg), height (171.71 ± 7.12 in cm), and body mass index in (23.91 ± 3.45 kg/m2) were found as reported. Motor nerve conduction velocities (wrist-elbow) of median nerve were found to be 57.92 ± 7.60 m/s for the left hand and 58.61 ± 5.77 m/s for the right hand. Conclusion: A standardized technique was used to determine the normative reference parameters of the motor NCV of the median nerve in the normative subjects and it was compared with the other authors’ parameters.

Climbing behavior of guarding males in the hermit crab Pagurus minutus: the effect of rivals, female size, and being weaponless

Male crustaceans engage in precopulatory mate-guarding to monopolize a female. However, a conspecific rival often takes the female from the guarding males during male–male contests, so guarding males should invest in behavior to decrease the rate of encounters with rivals, especially when they are potentially weak and guard a valuable female. We examined this idea using a net-climbing (avoidance) response by precopulatory guarding males of the hermit crab Pagurus minutus. Guarding males more often climb revetment walls in the field than solitary males and females, and the guarders were larger in body size than the solitary males on the walls. Guarding males increased climbing effort in the presence of rivals compared to controls (no stimulus), but not when faced with a non-threat organism. Compared to intact guarding males, those without a major cheliped (“weaponless”) were less likely to succeed in defending their partner in direct fights, but increased climbing investment overall, rather than especially when a rival was present. Although female size positively correlates with clutch size in this species, male climbing height decreased with increasing size of the guarded female. We discuss the effectiveness and importance of climbing in this species as it relates to conditions at our study site and the general vulnerability of guarding males depending on weapon status.

\u201cIf you are on duty, you may be afraid to come out to attend to a person\u201d: fear of crime and security challenges in maternal acute care in Nigeria from a realist perspective

BackgroundMaternal and Child Health is a global priority. Access and utilization of facility-based health services remain a challenge in low and middle-income countries. Evidence on barriers to providing and accessing services omits information on the role of security within facilities. This paper explores the role of security in the provision and use of maternal health services in primary healthcare facilities in Nigeria.MethodsStudy was carried out in Anambra state, Nigeria. Qualitative data were initially collected from 35 in-depth interviews and 24 focus groups with purposively identified key informants. Information gathered was used to build a programme theory that was tested with another round of interviews (17) and focus group (4) discussions. Data analysis and reporting were based on the Context-Mechanism-Outcome heuristic of Realist Evaluation methodology.ResultsThe presence of a male security guard in the facility was the most important security factor that facilitated provision and uptake of services. Others include perimeter fencing, lighting and staff accommodation. Lack of these components constrained provision and use of services, by impacting on behaviour of staff and patients. Security concerns of facility staff who did not feel safe to let in people into unguarded facilities, mirrored those of pregnant women who did not utilize health facilities because of fear of not being let in and attended to by facility staff.ConclusionHealth facility security should be key consideration in programme planning, to avert staff and women’s fear of crime which currently constrains provision and use of maternal healthcare at health facilities.

남성 경비직 근로자의 고혈당증 및 고콜레스테롤혈증에 영향을 미치는 요인

남성 경비직 근로자의 고혈당증 및 고콜레스테롤혈증에 영향을 미치는 요인

Dominance, reproductive behaviours and female mate choice in sterilised versus non-sterilised invasive male crayfish

Many methods of controlling invasive crayfishes have limited success because they fail to target all life stages of the population, notably by capturing only large adults that can result in increased juvenile recruitment by removing intraspecific predation. An alternative approach uses the sterile male release technique that involves the mass release of sterile males into the environment, which then mate with fertile females, resulting in unfertilised eggs and, ultimately, reduced juvenile recruitment. This does, however, rely on the sterilised males exhibiting behaviours similar to non-sterilised (entire) males and remaining attractive to females during mate choice. Post-copulatory male guarding behaviour and female promiscuity might also be affected by male sterilisation. To test for the presence of normal reproductive behaviours in sterilised male American signal crayfish Pacifastacus leniusculus, a two-stage experiment examined how sterilisation affects female mate choice and promiscuity, male hierarchical status (relative dominance) and post-copulation guarding. Sterilised males showed similar reproductive behaviours to entire males and remained as attractive to females, with no differences in relative dominance. Post-copulation, guarding behaviours were also unaffected. Females did not display promiscuous behaviour and this was unaffected by whether males were entire or sterilised. The results demonstrated that sterilised males were equally as capable as entire males of achieving dominance and winning mates. In combination, these findings suggest that male sterilisation could be an effective control technique to help reduce juvenile recruitment in wild P. leniusculus populations by reducing reproductive success.

Indirect cue of paternity uncertainty does not affect nest site selection or parental care in a Pacific toadfish

Parents are expected to reduce offspring investment when confronted with reliable cues of compromised parentage, yet establishing which cues are reliable is an empirical challenge. Presenting a potential cuckolder to a breeding male is often used in experiments as an indirect cue of paternity loss. However, determining the reliability and hence the utility of this cue is an important but often-overlooked research step. Furthermore, cues of compromised parentage are typically manipulated only during the narrow time window(s) when copulations take place, and so we currently have a poor understanding of whether these cues also convey useful information at other critical timepoints in the reproductive cycle, such as during nest site selection. Here, we present a series of field and laboratory studies using a paternal care giving toadfish, the plainfin midshipman fish (Porichthys notatus) to address these questions. We tested whether the presence of a potential cuckolder near a potential nesting site reduces the odds that males will choose to nest at that site, or reduces the amount of care they provide for offspring. Overall, we found no clear effect of cuckolder presence on the likelihood that a male would occupy nor abandon a nesting site, nor on the amount of paternal care provided. The presentation of a single sneaker male may have been too weak a signal of cuckoldry to elicit a response from guarder males. Alternatively, a single sneaker male may not represent a severe enough threat to paternity to warrant a response. We highlight the importance of considering the diverse range of natural history and ecological factors that underlie paternity cue utility across different model organisms. Breeding decisions, such as which nesting sites to occupy or how much to invest into offspring, may be affected by external cues of parentage loss (e.g. cuckoldry) or risk thereof. Here, we tested whether the presence of a cuckolder male in the breeding environment affects male nest site selection and paternal care. Despite being a commonly used putative indirect cue of sperm competition and paternity loss, we found no clear evidence that the presence of a single sneaker male affected these breeding decisions. Our results underscore the importance of first establishing the utility of various cues, which involves considering the ecological context from which the cues arise, before using them to assess the mechanisms underlying animal decision-making.

Blood pressure variation in night shift male security guards in north Kerala

Background: In modern society, people have lost the classical 7 am–6 pm day work and nighttime sleep cycle. A huge working population is engaged in night shift, part-time work, weekend work, being on-call all the time, prolonged duty periods (12–24 h at a stretch), etc. Apart from the nature of the work, working time or work shift is a key issue that impacts human health. Aim and Objective: The objective of this study was to study the effect of night shift work on blood pressure (BP). Materials and Methods: The study was conducted on 200 security guards from north Kerala, who were divided into two groups based on the night and day shift duty. BP was measured using a sphygmomanometer (mercury). Results: The mean (± SD) systolic BP (SBP) in day shift security guards was 127.28 ± 9.417 and in night shift security guards was 131.08 ± 10.469. The mean (± SD) Diastolic BP (DBP) in day shift security guards was 80.68 ± 4.218 and in night shift security guards was 82.08 ± 3.792. Conclusion: We found a significant increase in SBP and DBP in night shift security guards compared to day shift security guards.

Behavior of "Intermediate" Males of the Dimorphic Squid Doryteuthis pleii Supports an Ontogenetic Expression of Alternative Phenotypes.

The expression of alternative reproductive tactics (ARTs) by different-sized males of loliginid squids has been extensively investigated. In loliginids, alternative phenotypes are characterized by discontinuous differences in behavior, body size, sperm deposition site, and morphology and functioning of ejaculates. Large consort males guard females, display agonistic behaviors toward rival consort males, and mate with females in the male-parallel (MP) position. Small sneaker males avoid fighting contests and instead adopt furtive behaviors to access females guarded by consort males, mating with females in the head-to-head (HH) posture. Recently, the reappraisal of preserved material from the loliginid squid Doryteuthis pleii showed that intermediate-sized males (so-called “intermediate” males) had both sneaker- and consort-like ejaculates, leading to the hypothesis of them being a transitional stage between both phenotypes. Here, we describe observations made in captivity showing that intermediate males can display agonistic behaviors toward consort males and mate with females in both mating positions, depending on the male’s current reproductive context, i.e., generally in HH, but switching to MP when the female is laying eggs. Such unusual findings of intermediate males simultaneously displaying behaviors of both sneaker and consort males comprise additional evidence corroborating the ontogenetic hypothesis for phenotypic expression of ARTs in this species. Taken together, our results indicate that (1) instead of competing with large consort males for female access and monopolization, small/young males adopt sneaker tactics to obtain mating opportunities, and (2) as they continue to grow, they gradually modify the morphology of their ejaculates and their mating behavior, going through an “intermediate” stage, before becoming large consort males.