Two Sides of the Same Coin? Consistency in Aggression to Conspecifics and Predators in a Female Songbird

Different forms of aggression have traditionally been treated separately according to function or context (e.g. aggression towards a conspecific versus a predator). However, recent work on individual consistency in behavior predicts that different forms of aggression may be correlated across contexts, suggesting a lack of independence. For nesting birds, aggression towards both conspecifics and nest predators can affect reproductive success, yet the relationship between these behaviors, especially in females, is not known. Here we examine free-living female dark-eyed juncos (Junco hyemalis) and compare their aggressive responses towards three types of simulated intruders near the nest: a same-sex conspecific, an opposite-sex conspecific, and a nest predator. We also examine differences in the strength of response that might relate to the immediacy of the perceived threat the intruder poses for the female or her offspring. We found greater aggression directed towards a predator than a same-sex intruder, and towards a same-sex than an opposite-sex intruder, consistent with a predator being a more immediate threat than a same-sex intruder, followed by an opposite-sex intruder. We also found positive relationships across individuals between responses to a same-sex intruder and a simulated predator, and between responses to a same-sex and an opposite-sex intruder, indicating that individual females are consistent in their relative level of aggression across contexts. If correlated behaviors are mediated by related mechanisms, then different forms of aggression may be expressions of the same behavioral tendency and constrained from evolving independently.     

Are Centrally Displaying Males Always the Centre of Female Attention? Acoustic Display Position and Female Choice in a Lek Mating Subterranean Insect

Several conceptual models seek to explain patterns of male display and factors that influence female mate choice in lek mating systems. The central advantage model predicts that males displaying at or near the lek centre should be more attractive to females than are males positioned along the lek periphery. Females may exhibit biases toward these centrally displaying males based on either spatial or display‐related cues. We tested the prediction of the central advantage model in investigating the importance of male display position in the subterranean and lek mating prairie mole cricket (Gryllotalpa major). Gryllotalpa major males form mating aggregations in the early spring and produce an acoustic advertisement signal from a constructed calling chamber at the soil surface. Pair formation occurs in the calling chamber, and males typically maintain these structures for the duration of the reproductive season. To assess whether G. major females exhibit a preference for males calling from centrally located acoustic burrows, we documented the spatial position and number of female attractions for all advertising males across the focal lek. Six spatial attributes related to display position were reduced using principal component analysis and examined for an association with male attractiveness. We found that in general, female attractions were distributed randomly across the lek; male attractiveness was not related to proximity to the lek centre nor to any factor associated with display position. The most highly attractive males, however, were located further from the lek centre and from nearest calling neighbours than other attractive males. Advertising males that segregate themselves within the aggregation and locate nearer the lek margin may gain a geometric advantage resulting in the increased probability of attracting a searching female.     

Female preference in the context of male–male interactions in Maylandia zebra of Lake Malawi

The mbuna cichlids of Lake Malawi are a diverse, monophyletic, and recently derived clade. Sexual selection is thought to have accelerated their rapid diversification, though the mechanism by which this has occurred remains unknown. In this study, we examine the effect that male–male interactions have on female preference. We first used a short interaction experiment as a proxy for male dominance. We then measured female preference for (1) a single, isolated male; (2) a group of three, highly ranked males, relative to a group of lower ranked males; and (3) a group of three, mixed-ranked males against a similar group of mixed-rank males. We found that male dominance was highly correlated with male standard length. Female preference for male standard length and for dominance rank was significant in both isolated and group interactions. However, females only showed preference for groups of interacting males when males were segregated by dominance rank, not when groups were composed of both dominant and subordinate males. The results suggest that male–male contests influence female mating decisions. By investigating the rules that dictate the outcomes of such interactions we can elucidate the role that behavior plays in the diversification of this species-rich lineage.     

Female perception of a partner’s mate value discrepancy and controlling behaviour in romantic relationships

Mate value discrepancy (MVD) between heterosexual partners is an important factor influencing relationship satisfaction which, in turn, has an effect on the quality and the stability of the relationship. Therefore, partners’ involvement in mate retention behaviours, such as controlling behaviours, can be related to MVD and our study aims to determine whether such an association exists. In order to do so, we analysed female perception of MVD and their opinion regarding the intensity of controlling behaviours performed by themselves as well as their romantic partners. Female perception of the intensity of controlling behaviours performed by both partners was the highest in couples where a woman assesses her own mate value (MV) as higher than her partner’s MV and significantly different than in relationships where male MV exceeded those of the female. Our study also indicates that MVD should be taken into account when analysing sex differences in intensities of mate retention behaviours. Finally, we provide evidence supporting the significance of the relationship length for controlling behaviour intensity. Findings are discussed within an evolutionary perspective.     

Dynamics of Female–Female Relationships in Wild Cebus capucinus: Data from Two Costa Rican Sites

International Journal of Primatology - Three questions about female-female relationships remain largely unexplored in female-philopatric platyrrhines. First, to what extent is female dominance...     

Group Structure and Female Cooperative Networks in Australia’s Western Desert

The division of labor has typically been portrayed as a complementary strategy in which men and women work on separate tasks to achieve a common goal of provisioning the family. In this paper, we propose that task specialization between female kin might also play an important role in women’s social and economic strategies. We use historic group composition data from a population of Western Desert Martu Aborigines to show how women maintained access to same-sex kin over the lifespan. Our results show that adult women had more same-sex kin and more closely related kin present than adult men, and they retained these links after marriage. Maternal co-residence was more prevalent for married women than for married men, and there is evidence that mothers may be strategizing to live with daughters at critical intervals—early in their reproductive careers and when they do not have other close female kin in the group. The maintenance of female kin networks across the lifespan allows for the possibility of cooperative breeding as well as an all-female division of labor.     

Effects of Transient and Continuous Wheel Running Activity on the Upper and Lower Limits of Entrainment to Light‐Dark Cycles in Female Hamsters

The entrainment limits to light‐dark cycles can be modified by the experimental conditions under which they are tested. Among the factors that may influence entrainment is the amount of wheel running exerted by the animal. In the present work, the effects of transitory and continuous wheel running on entrainment to light‐dark cycles were tested using a range of T cycles at the entrainment limits. Four groups of female hamsters were submitted to 1 h stepwise changes in T cycles. Two groups were exposed to T cycles of which the period was shortened at the lower limit from T22 to T18, and the other two groups were exposed to cycles that lengthened at the upper limit from T27 to T32. One of the groups at the lower limit and one at the upper limit had continuous access to a running wheel, while the others had the wheel locked, except at certain T when a lack of period control by T cycle appeared. The study demonstrates that access to running wheel widens the limits of entrainment to LD cycles. Specifically, the following observations were made: the effects of wheel running for entrainment were more evident in the groups with continuous access to wheel, as they did entrain to T19 and T32; continuous access to a wheel produced aftereffects only after T19, but not under T32; and when animals without a wheel showed relative coordination, unlocking the wheel favored entrainment in all the animals at T31, but in only 1 out 6 at T19. All of these indicate a different effect of the wheel running on the upper and lower limits of entrainment.     

Whom to Groom and for What? Patterns of Grooming in Female Barbary Macaques (Macaca sylvanus)

Grooming is one of the most conspicuous social interactions among nonhuman primates. The selection of grooming partners can provide important clues about factors relevant for the distribution of grooming within a social group. We analyzed grooming behavior among 17 semi-free ranging female Barbary macaques (Macaca sylvanus). We tested whether grooming is related to kinship, rank and friendship. Furthermore, we tested whether grooming is reciprocated or exchanged for rank related benefits (i.e. lower aggression and increased tolerance whilst feeding). We found that in general grooming was reciprocally exchanged, directed up the hierarchy and at the same time affected by friendship and kinship. Grooming was more frequent among individuals with higher friendship values as well as amongst related individuals. We also divided our data set on the basis of rank difference and tested if different power asymmetries between individuals affected the tendency to exchange grooming for rank related benefits and grooming reciprocation. In support of our initial hypothesis our results show that the reciprocation of grooming was a significant predictor of grooming interactions between individuals of similar rank, but not between those individuals more distantly separated in the social hierarchy. However, we did not find any evidence for grooming being exchanged for rank related benefits in either data set. Our results, together with previously published studies, illustrate the behavioral flexibility of macaques. It is clear that multiple studies of the same species are necessary to gather the data required for the solid comparative studies needed to shed light on patterns of grooming behavior in primates.     

Reproductive Experience and the Response of Female Sprague�CDawley Rats to Fear and Stress

The present work examines the relationship between reproductive experience (comprising breeding, parturition, and lactation) and the behavioral and hormonal processes of fear and stress in the female laboratory rat. Previous research has indicated that reproductive experience functions to decrease the female''s stress response in potentially harmful environments, thereby providing her with numerous survival benefits, including decreased fearfulness, increased aggression, and refined hunting skills. This study was designed to determine how nulliparous (no reproductive experience), primiparous (1 reproductive experience) and multiparous (at least 2 reproductive experiences) rats respond to a Pavlovian paradigm of learned fear, involving the pairing of a neutral stimulus (conditioned stimulus) with an aversive stimulus (unconditioned stimulus). We report evidence that reproductive experience is linked with fear-response and anxiety-like behaviors. Our findings indicate that reproductive experience has an additive effect: primiparous mothers showed a different response to the paradigm of conditioned fear not only compared with those of nulliparous rats as well as multiparous mothers. Assessing the complex interconnections among the behavioral and physiologic measures recorded in this study, multidimensional scaling confirmed a clear separation among the 3 groups of rats in terms of the behavioral and physiologic responses to the experimental paradigm, supporting the conclusion that reproductive experience influences the maternal mind.Stress, fear, and lack of adequate stimuli can constitute a serious problem for laboratory animals. Although several studies have investigated various social and environmental changes to improve the health of laboratory animals, the literature on husbandry regimen and reproductive experience is scarce.^{3,23,44,56,58} Pregnancy and lactation represent the quintessence of change in mammals.^13,38 Reproduction entails high physiologic costs, especially in small mammals like rodents, including increased energy and nutrient demands, making the connection between husbandry and health in laboratory rats even more compelling.⁴⁹ Extensive neuroendocrine and behavioral modifications ensure mothers the flexibility to meet their own survival needs with the survival of their offspring in most environmental contingencies.^30,46 The long-term effects of these changes on the somatic and psychologic development of infants are well-known and pervasive in most mammals: from immediate infant survival to the ability to cope with stress during adulthood.^5,7,22,26,43 Several studies have indicated that the long-term consequences on mothers themselves are as compelling. Although some authors have found a significant decrease in cell proliferation in the dentate gyrus of the hippocampus in primiparous and multiparous rats during the postpartum period, associated with temporary impaired learning skills,¹⁵ others have found that motherhood can improve spatial cognition, learning and memory,^9,27,33,42 through mechanisms based on increased glucocorticoid production.^31,41 The combination of improved behavioral performances and increased physiologic stress in mothers is hardly surprising considering that the sequence of modifications during pregnancy involves, as a cascade of events, the whole body and shapes the inherently plastic central nervous system to cope with the extra challenges of providing for offspring. At the pinnacle of its fruition, the maternal brain is responsible for a complex set of behaviors that mold mothers in every aspect of their life.^28,29 In this scenario, we expect that empirical examinations of laboratory female rats with differential reproductive experience would yield significant differences in both the fear and stress response of maternal and virgin rats. Because stress and fear can impair the health of research animals and, if not controlled for, confound results obtained in experimental data, it is important to evaluate how reproductive experience can modify both stress and fear responses. Previous studies have indicated that, when confronted with a stressful stimulus, maternal rats display fewer stress-related behaviors than do nonmaternal rats.^32,57One common method of examining the animal''s reaction to a threatening environment is to use a Pavlovian model of learned fear. The neural circuitry of learned fear, involving the association of a conditioned stimulus or context with an unconditioned stimulus, is of particular interest because learned fear processes involve multiple cognitive functions including predicting, representing, and defining relationships between events.⁴⁵ The literature discussing the neural correlates of learned fear is vast and, further, agrees that the amygdala is the central brain structure responsible for learned fear. In fact, bilateral damage to the amygdala seriously impairs Pavlovian fear conditioning.^8,53 Studies conducted in developing rats revealed that different nuclei of the amygdala process sensory information of different modalities, mediate unconditioned freezing behavior, and may be involved in developmental changes in the fear response in young rats.¹⁴ Research elucidating a relationship or lack thereof between reproductive experience and changes in fear response is limited presently.^19,55 Examinations of unconditioned fear and maternal experience have suggested that an attenuated stress response and an overall decrease in fearfulness provides numerous survival benefits, such as enhanced and increased hunting and gathering skills, exploration, social awareness, and aggression, to the female rat.^21,37,50,51 Because survivability is dependent upon the prediction and appropriate response to threatening stimuli, this research paradigm can provide pertinent information about the animal''s fitness, thus providing critical information on both the health of animals and the quality of experimental data.Pregnancy, lactation, and the complex behavioral repertoire comprising maternal care constitute an expensive metabolic and genetic investment that is pivotal to species survival.^11,52 Alterations of the female brain due to occurrences of several cycles of pup exposure are reflected in many aspects of maternal life, including fear responses, activation of the hypothalamic–pituitary–adrenal axis, and anxiety.¹⁰ In the present work, we assessed whether reproductive experience plays a specific role on fear response and how this response activates the hypothalamic–pituitary–adrenal axis and interacts with anxiety-related behaviors in rats. We also assessed whether these effects are additive, that is, whether multiparous mothers (2 or more pregnancies) have a different fear response than do primiparous mothers (only 1 pregnancy). On the basis of information provided by previous studies, we hypothesized that during the retention–testing trials of the conditioning model, maternal subjects (primiparous and multiparous groups) would express fewer fear-related (freezing) behaviors than would nonmaternal subjects (nulliparous group). We further hypothesized that the maternal groups would express anxiety-related behaviors less frequently than would the nonmaternal group during the retention–testing trials. In addition, we speculated that the nulliparous group would exhibit significantly higher activation of the hypothalamic–pituitary–adrenal axis than would the reproductive groups (primiparous and multiparous), as measured by corticosterone concentrations after the fear-conditioning training trials.     

The Development of Male and Female Gametophyte in an Endangered Plant—Ranalisma rostratum Stapf (Alismataceae)

Ranalisma rostratum Stapf is a rare and endangered species． This paper deals with the development of its male and female gametophytes and probes the relationship between the process of reproduction and the cause which made this species endangered． The meiosis of microspore mother cells is successive cytokinesis and the microspore tetrads are isobilateral． Pollen grains are 3-celled when shed． The ovule is anatropous,bitegmic and tenuinucellate． The micropylar dyad cell usually desenerates soon after its formation, and the chalazal dyad cell develops into a Allium type embryo sac． During the development of embryo sac both polar nuclei are respectively located at the two ends of central cell,and they maintain this situation until the micropylar polar nucleus takes part in fertilization． Features of the embryo sac of Ranalisma rostratum Stapf are discussed．     

Effects of Chronic Restraint Stress and 17-β-Estradiol Replacement on Oxidative Stress in the Spinal Cord of Ovariectomized Female Rats

Previous studies have shown sex-specific oxidative changes in spinal cord of rats submitted to chronic stress, which may be due to gonadal hormones. Here, we assessed total radical-trapping potential (TRAP), superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities and lipid peroxidation (evaluated by the TBARS test) in the spinal cord of ovariectomized (OVX) female rats. Female rats were subjected to OVX, and half of the animals received estradiol replacement. Animals were subdivided into controls and chronically stressed (for 40 days). Our findings demonstrate that chronic stress decreased TRAP, and increased SOD activity in spinal cord homogenates from ovariectomized female rats and had no effect on GPx activity. On the other hand, groups receiving 17β-estradiol replacement presented a decreased GPx activity, but no alteration in TRAP and in SOD activity. No differences in the TBARS test were found in any of the groups analyzed. In conclusion, our results support the idea that chronic stress induces an imbalance between SOD and GPx activities, additionally decreasing TRAP. Estradiol replacement did not reverse the effects of chronic stress, but induced a decrease in GPx activity. Therefore, estradiol replacement in ovariectomized chronically stressed rats could make the spinal cord more susceptible to oxidative injury.     

Variations in Fecundity and Egg Size of Female Nile Tilapia, Oreochromis niloticus, from Man-made Lakes of Côte D'Ivoire

Fecundity and oocyte size of Oreochromis niloticus females were studied over a period of two annual cycles in six small agropastoral and three large hydroelectric reservoirs of Côte d'Ivoire. Important differences in fecundity and oocyte size were observed among populations and within the same population between successive years. An inverse correlation was found between size and number of oocytes produced by females. This inverse relationship occurred for a constant spawn weight during the first year of study, but not during the second year. Monthly mean residuals of regressions between fecundity and female body weight have shown a seasonal variation in fecundity. The peak of fecundity corresponded with the maximum resource availability and the flooding eminence, which may have a great impact on parents and offspring fitness.     

Evaluation of Functional Limitations in Female Soccer Players and Their Relationship with Sports Level – A Cross Sectional Study

The main objective(s) of the study

The aim of this study was to analyze: a) abnormalities in the length of lower limb muscles, b) the correctness of movement patterns, and c) the impact of functional limitations of muscles on the correctness of fundamental movement patterns in a group of female soccer players, in relation to their skill level.

Materials and Methods

21 female soccer players from Polish Ekstraklasa and 22 players from the 1^st Division were tested for lower limb muscle length restrictions and level of fundamental movement skills (with the Fundamental Movement Screen™ test concept by Gray Cook). Chi-square test was used for categorical unrelated variables. Differences between groups in absolute point values were analyzed using the non-parametric Mann-Whitney U test. Statistical significance was set at p<0.05.

Results

Statistically significant higher number of measurements indicating an abnormal length of rectus femoris was observed in the 1st Division group (p = 0.0433). In the group of Ekstraklasa the authors obtained a significantly higher number of abnormal hamstring test results (p = 0.0006). Ekstraklasa players scored higher in the rotational stability test of the trunk (p = 0.0008), whereas the 1st Division players scored higher in the following tests: deep squat (p = 0.0220), in-line lunge (p = 0.0042) and active straight leg raise (p = 0.0125). The results suggest that there are different functional reasons affecting point values obtained in the FMS™ tests in both analyzed groups.

Conclusions

The differences in the flexibility of rectus femoris and hamstring muscle observed between female soccer players with different levels of training, may result from a long-term impact of soccer training on the muscle-tendon system and articular structures. Different causes of abnormalities in fundamental movement patterns in both analyzed groups suggest the need for tailoring prevention programs to the level of sport skills represented by the players.     

Measuring Discrimination in South Korea: Underestimating the Prevalence of Discriminatory Experiences among Female and Less Educated Workers?

Objectives

To investigate the possibility that Koreans show different patterns in reporting discriminatory experiences based on their gender and education level, we analyzed the participants who answered “Not Applicable” for the questions of discriminatory experiences that they were eligible to answer.

Methods

Discriminatory experiences in eight social situations were assessed using the 7^th wave of Korean Labor and Income Panel Study. After restricting the study population to waged workers, a logistic regression model was constructed to predict the probability that an individual has experienced discrimination based on the observed covariates for each of eight situations, using the data of participants who answered either Yes or No. With the model fit, the predicted logit score of discrimination (PLSD) was obtained for participants who answered Not Applicable (NA), as well as for those who answered Yes or No. The mean PLSD of the NA group was compared with those of the Yes group and the No group after stratification by gender and education level using an ANOVA model.

Results

On the questions of discrimination in getting hired and receiving income, the PLSD of the NA group was significantly higher than that of the No group and was not different from that of Yes group for female and junior high or less educated workers, suggesting that their NA responses were more likely to mean that they have experienced discrimination. For male and college or more educated workers, the NA group had a PLSD similar to that for the No group and had a significantly higher PLSD than the Yes group, implying that their NA responses would mean they that they have not experienced discrimination.

Conclusions

Our findings suggest that the responses of NA on the discrimination questionnaire may need different interpretation based on the respondents'' gender and education level in South Korea.     

Female Defensibility in a Small Troops of Japanese Macaques vis-à-vis Nontroop Males and Copulation on the Periphery of the Troop

I provide data compiled over 4 yr on the mating behavior in small troops of wild Japanese macaques on Yakushima Island. The key parameters are the number of sexually receptive females, the number of nontroop males (NTMs), and copulation on the periphery of the troop. I analyzed the following aspects: 1) changes in the proportion of copulation with high-ranking males (HRMs) and NTMs, 2) variations in factors such as fluctuation in the number of sexually receptive females and troop males and their effects on the number of visiting NTMs, 3) the effect of attempted interruption of mounting series by other males, and 4) some aspects of copulation on the periphery of the troop. Throughout the study, 56% of the total number of females mated most frequently with the α-male in a single mating season. However, the relative mating success of HRMs varied over the years and between individuals. The number of visiting NTMs varied depending on the number of receptive females and troop males. Females tended to mate with the NTMs when they appeared around their troops. The direct effect of interruption of the mounting series by other males is equivocal. The females mated with the low-ranking males (LRMs) and NTMs on the periphery of the troop, which increased the possibility of mounting series ending with ejaculation. Females actively sought opportunities for copulation on the periphery of the troop by moving there or initiating close proximity with LRMs and NTMs there. On Yakushima Island, the mating success of HRMs was not always as high as that predicted by the priority of access model. The injury status of the HRM, the number of visiting NTMs, and female choice are all considered to influence a male’s mating success.     

Female Copulation Calls in Guinea Baboons: Evidence for Postcopulatory Female Choice?

We tested the hypothesis that primate female copulation calls are a form of postcopulatory female choice. We collected data on female sexual swellings, sexual and agonistic behavior, copulation calls and postcopulatory behavioral interactions in a multimale-multifemale captive group of Guinea baboons over a 3-mo period. Males copulated with only a few females, and females copulated with only 1 or 2 different males in the group, suggesting a harem-like mating system similar to that of hamadryas and gelada baboons. Female copulations were most likely to occur at peak sexual swellings and male copulatory success was accounted for by dominance rank and age. Variation in female tendencies to call after copulation is best explained by the copulatory success of the male with which each female copulated the most and by the number of copulating partners. The findings are consistent with predictions that calls are likely to be associated with copulation with preferred males and the risk of sperm competition. The prediction that copulation calls increased the probability of postcopulatory mate guarding is also supported. Taken together, the findings suggest that female copulation calls may play an important role in postcopulatory sexual selection and in particular in the expression of postcopulatory female choice in primate species in which females have little opportunity to choose their mates or female mate choice is costly or both.     

Mastitis in the Lactating Mink Female (Mustela vison S.) and the Development of “Greasy Kits”

“Greasy kits” is the result of a multifactorial disease complex with few known definitive aetiological factors. Mastitis has been hypothesized as a triggering factor although classical clinical signs of mastitis (rubor, tumor, dolor, calor) are rarely seen in lactating Danish mink females. In this study we sacrificed 2 groups of lactating mink females with a total of 78 mammary glands at day 19–30 after giving birth. The first group had raised normal mink kits while the other group had suffered severe attacks of greasy kits. We found no clinical or histopathological evidence of mastitis but isolated streptococci and staphylococci from 2 mammary glands in females raising greasy kits. These glands showed no clinical or histological signs of inflammation attributable to bacteria and we conclude that mastitis is not necessary for the generation of greasy kits.     

Female Cone Development in Fokienia, Cupressus, Chamaecyparis and Juniperus （Cupressaceae）

The ontogeny and vascular systems of female cones of the Fokienia, Oupressus, Ohamaecyparis and Juniperus were investigated in detail using scanning electron microscopy (SEM) and conventional light microscopy. In the species examined, in the axils of the bracts, the first recognizable structure was a broad meristematic swelling, from which ovules developed. No ovuliferous scales developed during the ontogeny of the female cones. The number of ovules and ovule developing sequence displayed considerable variation in different species. However, development of the bracts was similar in all of the investigated species. Following pollination, the foliage-like bracts became peltate bract scales due to intercalary expansion, and global cones formed. In addition, the vascular system in the bract scales became intricate, and inverted vascular bundles emerged in the adaxial of the mature bracts. Based on these observations, a morphological interpretation and possible evolutionary trend of the Cupressaceae female reproductive structures was discussed.