Sexual behavior and hormone levels during the menstrual cycles of rhesus monkeys.

The sexual interactions of 10 pairs of rhesus monkeys were observed during a control and an experimental menstrual cycle of each female. During the experimental cycle the females were treated with an antiandrogen, flutamide. Daily peripheral serum levels of estradiol, testosterone, and progesterone in each female were determined by radioimmunoassay. Sexual behavior did not correlate reliably with female serum concentrations of any hormone measured nor with the menstrual cycle stage. Administration of the antiandrogen to the females did not affect the sexual behavior of the pairs, although female serum levels of estradiol and testosterone were reduced. It was concluded that although female ovarian hormones may influence rhesus sexual interactions under some circumstances, the normal hormonal fluctuations during the menstrual cycle need not regulate this behavior; a knowledge of an intact rhesus female's hormonal condition does not allow accurate predictions about behavior displayed during laboratory pair tests with a male.     

The variability of some motor components of social play and agonistic behaviour in infant eastern coyotes, Canis latrans var

The duration and stereotypy (in terms of duration) of three actions, stand-overs (SO), generalbites (GB), And scruff-bites (SB), were measured during social play and agonistic interactions in infant eastern coyotes (Canis latrans). The rate of biting was also calculated. We found: (1) SO's and GB's lasted a significantly shorter time during play; (2) when performed during playful interactions, all three acts showed more stereotypy; (3) there was no significant difference between the rates of occurrence of biting during the two situations. A discussion of the 'exaggerated' nature of play behaviour is presented, particularly concerning the form of motor actions that are used during this activity.     

Playing it cool: Characterizing social play,bout termination,and candidate play signals of juvenile and infant Tibetan macaques(Macaca thibetana)

Play behaviors and signals during playful interactions with juvenile conspecifics are important for both the social and cognitive development of young animals.The social organization of a species can also influence juvenile social play. We examined the relationships among play behaviors, candidate play signals, and play bout termination in Tibetan macaques(Macaca thibetana) during juvenile and infant social play to characterize the species play style. As Tibetan macaques are despotic and live in groups with strict linear dominance hierarchies and infrequent reconciliation, we predicted that play would be at risk of misinterpretation by both the individuals engaged in the play bout and by those watching, possibly leading to injury of the players. Animals living in such societies might need to frequently and clearly signal playful intent to play partners and other group members to avoid aggressive outcomes. We gathered video data on 21 individually-identified juvenile and infant macaques(one month to five years of age)from the Valley of the Wild Monkeys, Mt. Huangshan,China. We used all-occurrence sampling to record play behaviors and candidate play signals based on an ethogram. We predicted that play groups would use multiple candidate play signals in a variety of contexts and in association with the number of audience members in proximity to the players and play bout length. In the 283 playful interactions we scored,juvenile and infant macaques used multiple body and facial candidate play signals. Our data showed that juvenile and infant Tibetan macaques use a versatile repertoire of play behaviors and signals to sustain play.     

The use of vocal signals in the social play of barbary macaques

Field studies in various species ofMacaca (Cercopithecidae) provided evidence for specific visual displays that typically accompany playful interactions. The aim of our study was to examine whether and when playing individuals would use auditory displays, i.e. vocalizations that often occur during social play as well. The study was conducted on a population of semi-free Barbary macaques (Macaca sylvanus) with a special focus on the composition and dynamics of playful wrestling (synonymous term: ‘rough-and-tumble play’). Analyses of dyadic encounters between subadult males allowed us to distinguish five types of playful behaviours and three types of vocalizations. The latter were clearly linked to encounters where effects of visual signals were impaired, e.g. during close body contact. During wrestling, vocalizations tended to increase in the beginning of an encounter, whereas the last seconds of wrestling often showed a decline in vocalization rate. Our results allowed us to conclude that these vocalizations may supplement or in many cases even substitute interactional effects of visual signals, e.g. the ‘play face.’     

Analysis of tufted capuchin (Cebus apella) courtship and sexual behavior repertoire: changes throughout the female cycle and female interindividual differences

Sexual solicitations and initiative (proceptivity, sensu Beach [1976] Horm Behav 7:105-138) are important components of the sexuality of females of many primate species. In the tufted capuchin (Cebus apella), female proceptivity characterizes the species' mating system. In study 1, we defined and discussed 20 behavioral patterns based on the observation of 6 females and 5 males living in two social groups. In study 2, each behavior, including mounting activity, was quantitatively assessed during the periovulatory and nonperiovulatory cycle phases of 4 females, detected on the basis of urinary progestin levels (N = 20 ovulatory cycles, 5 for each female); moreover, we monitored changes in females' social interactions (agonism, grooming activity, and play). Nine of the behaviors typically used by the female during courtship and in sexual interactions showed a dramatic increase during the periovulatory phase. Though males mounted females at an apparently higher rate during the periovulatory than the nonperiovulatory phase, the difference was not significant. However, when adult male mounting is separated into those which occur within play and nonplay contexts, there is a significant periovulatory phase effect for mounts not associated with play. Females groomed adult males at the same rate throughout the cycle. Agonism and play did not show any phase effect; however, females' avoidance of adult males significantly increased during the periovulatory phase. Finally, each female made a statistically different use of the behavioral repertoire by performing some behaviors more than others. This variability among females during courtship calls for further research into whether it affects mating success.     

The ontogeny of play in feral olive baboons (Papio anubis)

Behaviours that always appear playful (play markers) are distinguished from behaviours that appear playful in some contexts, but not others (context-dependent play components). Age changes in the frequency of performance of both kinds of playful behaviours are described, as are age changes in the frequency with which context-dependent play components accompany play markers in baboon social interactions. Some quantitative properties of social interactions containing and lacking play markers are compared. Interactions with play markers last longer and have a higher rate of change of constituent behaviours than interactions without. Animals are also more persistent in the face of changes in their partner's behaviour in interactions with play markers. It is suggested that an attempt to produce a definition of play is not a useful enterprise, but that it is important to investigate causal mechanisms underlying behaviours that appear playful to human observers, and to clarify the relationships among those mechanisms. Data are presented suggesting that at least two sets of mechanisms, not totally separate, underly the performance of baboon social play. Functions of the behaviours controlled by these mechanisms are discussed.     

Automatic Imitation in Rhythmical Actions: Kinematic Fidelity and the Effects of Compatibility,Delay, and Visual Monitoring

We demonstrate that observation of everyday rhythmical actions biases subsequent motor execution of the same and of different actions, using a paradigm where the observed actions were irrelevant for action execution. The cycle time of the distractor actions was subtly manipulated across trials, and the cycle time of motor responses served as the main dependent measure. Although distractor frequencies reliably biased response cycle times, this imitation bias was only a small fraction of the modulations in distractor speed, as well as of the modulations produced when participants intentionally imitated the observed rhythms. Importantly, this bias was not only present for compatible actions, but was also found, though numerically reduced, when distractor and executed actions were different (e.g., tooth brushing vs. window wiping), or when the dominant plane of movement was different (horizontal vs. vertical). In addition, these effects were equally pronounced for execution at 0, 4, and 8 s after action observation, a finding that contrasts with the more short-lived effects reported in earlier studies. The imitation bias was also unaffected when vision of the hand was occluded during execution, indicating that this effect most likely resulted from visuomotor interactions during distractor observation, rather than from visual monitoring and guidance during execution. Finally, when the distractor was incompatible in both dimensions (action type and plane) the imitation bias was not reduced further, in an additive way, relative to the single-incompatible conditions. This points to a mechanism whereby the observed action’s impact on motor processing is generally reduced whenever this is not useful for motor planning. We interpret these findings in the framework of biased competition, where intended and distractor actions can be represented as competing and quasi-encapsulated sensorimotor streams.     

Translocation mechanism of P-glycoprotein and conformational changes occurring at drug-binding site: Insights from multi-targeted molecular dynamics

P-glycoprotein (P-gp) is well known for multidrug resistance in drug therapy. Its over-expression results into the increased efflux of therapeutic agents rendering them inefficacious. A clear understanding of P-gp efflux mechanism and substrate/inhibitor interactions during the course of efflux cycle will be crucial for designing effective P-gp inhibitors, and therapeutic agents that are non-substrate to P-gp. In the present work, we have modeled P-gp in three different catalytic states. These models were utilized for elucidation of P-gp translocation mechanism using multi-targeted molecular dynamics (MTMD). The gradual changes occurring in P-gp structure from inward open to outward open conformation were sampled out. A detailed investigation of conformational changes occurring in trans-membrane domains (TMDs) during the course of catalytic cycle was carried out. Movements of each TM helices in response to pronounced twisting and translatory motion of NBDs were measured quantitatively. The role of intracellular coupling helices (ICHs) during the structural transition of P-gp was studied, and observed as vital links for structural transition. A close observation of displacements and conformational changes in the residues lining drug-binding pocket was also carried out. Further, we have analyzed the molecular interactions of P-gp substrates/inhibitors during the P-gp translocation to find out how stable binding interactions of a compound at drug-binding site(s) in open conformation, becomes highly destabilized in closed conformation. The study revealed striking differences between the molecular interactions of substrate and inhibitor; inhibitors showed a tendency to maintain stable binding interactions during the catalytic transition cycle.     

Nonbreeding season pairing behavior and the annual cycle of testosterone in male and female downy woodpeckers, Picoides pubescens

Studies in birds show that testosterone (T) concentrations vary over the annual cycle depending on mating system and life history traits. Socially monogamous species show pairing behavior throughout the year and low levels of male-male aggression and are underrepresented in these studies, yet the function of testosterone could be particularly important for sexual and social interactions occurring outside the breeding season. We measured fecal T concentrations over the annual cycle and the frequency of interactions between male and female downy woodpeckers (Picoides pubescens) from late fall through early spring. We validated the fecal assay by collecting blood in conjunction with a subsample of our fecal samples: fecal T correlated with circulating levels in the blood. The annual peak level of T in males was relatively low and short-lived, similar to that of other bird species with low levels of male-male aggression and high paternal care. The annual cycle of female T resembled the male pattern, and the ratio of male T to female T was close to 1.0. Likewise, the frequency of aggression among females was similar to the frequency among males. Overall, testosterone levels in both sexes were variable, even in winter. In other bird species, sexual behavior during nonbreeding periods correlates with circulating levels of T in males. Based on this observation, we tested the hypothesis that T in winter was positively related to the frequency of interaction between mated downy woodpeckers. The results showed no such relationship. We discuss this finding and further relate the annual cycle of T in both males and females to behaviors that appear to facilitate mate choice and retention of the pair bond during conspecific challenge.     

Vibrational communication during spawning behavior in the himé salmon (landlocked red salmon,Oncorhynchus nerka)

Summary Sexual behaviors of the salmon are composed of a stimulus-reaction chain, which ensures synchronous spawning between the sexes and successful fertilization. To characterize the signals involved in such a stimulusreaction chain, the body vibration and electromyographic activity of the trunk muscles during spawning were simultaneously recorded from freely behaving male and female pairs of himé salmon (landlocked red salmon,Oncorhynchus nerkd) and were analyzed in combination with a videographic analysis of behavior sequences. The results showed that the himé salmon have an elaborate communication system in which characteristic vibrational signals are exchanged. These are produced by body vibration due to trunk muscle activity related to spawning and are transmitted between the sexes with an accurate timing through the stimulus-reaction chain. They act as timing cues to synchronize gamete release and are thought to be shared among a wide variety of fishes. It was hypothesized that the lateral line sense is involved in the detection of these vibrational signals. Furthermore, based on the sequence matrix analysis as well as on information theory, intersexual behavioral sequences during spawning were analyzed statistically. The results showed that statistically significant interactions occur between the sexes and statistically significant amounts of information are transmitted through the interactions, supporting the results from recording experiments mentioned above. Characters of the signalling system and possible origins of the vibrational signals are also discussed.     

Sexual conflict is not counterbalanced by good genes in the laboratory Drosophila melanogaster model system

Sexual conflict theory is based on the observation that females of many species are harmed through their interactions with males. Direct harm to females, however, can potentially be counterbalanced by indirect genetic benefits, where females make up for a reduction in offspring quantity by an increase in offspring quality through a generic increase in offspring fitness (good genes) and/or one restricted to the context of sexual selection (sexy sons). Here, we quantify the magnitude of the good genes mechanism of indirect benefits in a laboratory-adapted population of Drosophila melanogaster. We find that despite high-standing genetic variance for fitness, females gain at most only a modest benefit through the good genes form of indirect benefits--far too little to counterbalance the direct cost of male-induced harm.     

Sexual dimorphism,temporal niche differentiation,and evidence for the Jack Sprat effect in an annual dioecious plant

Sexual dimorphism in dioecious plants often occurs as a consequence of the different resource requirements of females and males, especially during reproduction. The contrasting reproductive roles of the sexes can influence the phenology of growth, plant size, and flowering time, with implications for the intensity of competitive interactions within and between the sexes. Here, we investigate the influence of contrasting nutrient regimes and intra-sexual and inter-sexual competition on the expression of sexual dimorphism in life-history traits and biomass allocation throughout the life cycle of the dioecious annual Rumex hastatulus Baldw. (Polygonaceae). Development of a sex-specific marker enabled us to quantify the influence of competition on sex-specific differences in mortality and vegetative traits. We were particularly interested in determining whether the overall performance of the sexes might differ between the two forms of intra-specific competition, potentially providing evidence for sexual specialization in resource acquisition and niche differentiation. Our results indicated that although patterns of sexual dimorphism were dynamic, they were largely insensitive to nutrient conditions. We found that intra-sexual competition was more severe than inter-sexual competition, differentially affecting mortality and most traits during the vegetative and particularly the reproductive stage of the life history. Female trait values generally increased more under inter-sexual than intra-sexual competition in comparison to males. Our findings are consistent with temporal niche differentiation resulting from sexual specialization for different resource requirements and provide evidence for the “Jack Sprat effect.”     

The autecology of the chub, Squalius cephalus (L.), of the River Lugg and the Afon Llynfi

(1) The pattern of absolute atid relative gonad growth during the life-span and the seasonal gotiad cycle were determined from monthly samples of chub taken from two tributaries of the Herefordshire Wye. (2) A marked change in the pattern of absolute gonad growth was thought to indicate the attainment of sexual maturity. This was found to occur synchronously with corresponding changes in the pattern of body growth described previously and was in agreement with the age at which a seasonal gonad cycle was detectable. (3) Sexual maturity was attained during the eighth year of life (7+) in female chub and in males from the Afon Llynfi, but most males from the River Lugg matured a year earlier. (4) The chub gonads continued to increase in relative size after the attainment of sexual maturity. This was more evident in female chub. (5) Seasonal changes in the gonad condition and weight were followed. Gonad maturation occurred during spring and the gonad mass increased rapidly just prior to spawning. (6) Spawning occurred during June.     

Sociosexual behavior, male mating tactics, and the reproductive cycle of giraffe Giraffa camelopardalis

Female distribution exerts a major impact on male mating tactics. Giraffe cows have a reproductive cycle, and a social system, that should favor a male roaming reproductive tactic. We conducted a 2-year study of female Rothschild's giraffe (G. c. rothschildi) reproductive endocrinology in order to characterize attributes of the reproductive cycle and investigate how female endocrine and behavioral cues influence mating activity. We used non-invasive fecal steroid methods to determine reproductive state among females residing in a herd in a large outdoor enclosure. We found that females had an estrous cycle of 14.7 days and that they regularly had multiple ovarian cycles prior to conception. Adult males were more likely to associate with, and sexually investigate, females when they were cycling than when they were either pregnant or acyclic. During the estrous cycle, male-female proximity and sociosexual behavior were more pronounced during the probable fertile phase than the rest of the cycle. Sexual activity between giraffe coincided with the periovulatory period, with male interest in females peaking during the fertile window in the absence of proceptive behavior by females. We conclude that males detect reliable cues revealing female reproductive status and partition their reproductive effort in response to such cues. We propose that male giraffe adopt a roaming reproductive strategy with their large size, enabling them to search for and mate guard fertile females while minimizing metabolic costs.     

An ethogram forLemur fulvus

As a result of over 2000 hours of observation of two captiveLemur fulvus groups, their social behavior can now be provisionally described and categorized. Characteristic postures forL. fulvus include the normal standing or walking posture, often accompanied by low-pitched contact grunting, and the tightly curled resting posture. Disturbances in the vicinity of the group may lead to gradational changes in individual postures, culminating in the mob display. Greeting behaviors include passing without interaction, the sniff greeting, tactile greetings, and anogenital marking of one lemur by another. Allogrooming, mutual grooming, and reciprocal grooming may follow initial contact.L. fulvus individuals scent-mark spaces and objects, doing so at an increased rate during the mating season. Throughout most of the year little behavior occurs which can accurately be labelled ‘aggressive’. True agonistic behavior has only been observed during certain phases of the annual cycle: birth season, mating season, and the time of sexual maturation of juvenile animals. Sexual behavior is also rarely observed. Maternal behavior is interesting not only in terms of mother-infant interactions but also with regard to changes in mother-other interactions over time. Finally, play behavior can be distinguished from other kinds of behavior with similar behavioral components by looking at itsGestalt. Most play can be classified as either primarily locomotor/manipulative or primarily social.     

Sexual behavior of male New Zealand white rabbits in an intensive production unit

Sexual behavior in the male white New Zealand rabbit in intensive production units is not fully documented. Therefore, the objective of this work was to provide further information about the sexual behavior of this species in intensive production systems. Fourteen 6- to 12-month-old rabbits were studied for 6 months (July/December) when housed individually under natural photoperiod (19 degrees latitude north). They were mated once a week. When mated they were exposed at 6-min intervals to five oestrous females. The number of mounts, time between mounts, time and number of ejaculations, time between ejaculations, and also enuresis, grasping and kicking were recorded. Mounts (n=222) were observed and recorded. Males mated one to five times during each evaluative session. Enuresis was present only in one observation. Sexual aggressiveness such as grasping and kicking was present during 142 and 133 matings. Time for mounting and ejaculation in accumulated means (minutes, seconds, tenths) from the first to the fifth mount were noted and an accumulative average of 4.20 min for the fifth mounting was noted. Minimum times for ejaculation and next mating was 00:17:00 min and maximum was 05:33:03 min. It was concluded that sexual behavior in white New Zealand male rabbits remained unchanged through the duration of the period of study.     

Lipid metabolism of the female crab Pachygrapsus marmoratus during the moulting cycle

The moult induces important variations in the concentration and fatty acids composition of lipid classes during the moulting cycle of the female crab Pachygrapsus marmoratus regardless of the maturational degree of ovaries. Sexual maturity is characterized by a rise in lipids. Juveniles contain high levels of polyunsaturated fatty acids except in the ovary, whereas adults are composed mainly of monoethylenic acids. The moulting decrease of saturated fatty acids shows their importance during this crucial period, owing to their utilization as energy sources at the time of ecdysis. The late premoult fall of hepatopancreatic lipids results at once from inanition during the period before the exuviation and transfer of lipids through the hemolymph to the periphery in order to realize numerous changes occurring during the moulting process. The relative stability of lipid composition of ovaries in sexual pause during the moulting cycle agrees with a reduced metabolism of ovarian cells.     

Changes in social interactions during adolescence in male mandrills (Mandrillus sphinx)

The adolescent period in male mandrills extends from the time the testicles descend (at the age of 3-4 years) to the time adult characteristics develop (at the age of 10 years), and is thus one of the longest adolescent periods in cercopithecines. In this short cross-sectional study of 11 male mandrills (4.7-9.1 years old), we analyzed social behavioral patterns to investigate partner preference and changes in types of interactions throughout puberty. The mandrills were separated into two clusters on the basis of all of the social interactions scored, as well as the age and sex of the protagonist. During early to mid puberty, immature individuals interacted preferentially with other male adolescents and juveniles. Playing was an important activity, and some affiliative interactions with juveniles were observed. Older adolescents interacted more with adult males and females. These older adolescents were predominantly aggressive toward other adolescents, females, and juveniles, and showed little or no affiliative or playful behaviors. These results indicate a shift in social partners: older males interacted more frequently with adult males, and their behavior involved more aggression and less submission compared to younger adolescents, which showed predominantly submissive and playful behavior. These changes are consistent with preparation for dispersal and future intermale competition.