Individual- and Sex-related Strategies of Wrestling Play in Captive Squirrel Monkeys

The play behavior of 10 juvenile squirrel monkeys (Saimiri sciureus) was observed for 7 months in both mixed-sex and same-sex laboratory social groupings to identify strategies by which individuals may derive maximum benefit from play. Two types of play wrestling were identified: directional if one partner was on top of and dominating the other, and nondirectional if both partners hung from a perch and clasped each other equally. Males (N=5) wrestled more often, had longer bouts, and used proportionately more directional wrestling than did females (N = 5). Initiation Behaviors, leading predictably to play, were performed preferentially to certain partners, independent of affiliative (huddling) preferences. Both sexes performed more Initiation Behaviors to same-sex partners. Individuals, regardless of sex, preferred play partners whom they could dominate during directional wrestling; with partners whom they could not dominate, they preferred nondirectional wrestling, where partners were equal. The observed preferences are interpreted as evidence for individual strategies maximizing winning at directional wrestling. Role reversal is discussed as a strategy encouraging play between youngsters of diverse abilities, and as a means of providing needed experience in a variety of social roles.     

The ontogeny of social play in a feral troop of vervet monkeys (Cercopithecus aethiops sabaeus): The function of early play

We describe the ontogeny of social play over the first 30 weeks of age in a troop of feral vervet monkeys (Cercopithecus aethiops sabaeus) in Barbados. Play time increased rapidly for the first 10 weeks but remained relatively constant thereafter. The form of play changed with infant age; bouts became more frequent but of shorter duration. Play time, bout frequency, and bout duration at a given age differed between infants; younger infants altered their play patterns to complement those of older infants. All infants played more within their own year class than with older juveniles; play time increased with decreasing age difference between the infant and the play partner. Infants terminated a higher proportion of their play bouts the greater the age difference between themselves and their play partners. Preferred play partners are therefore individuals of similar age that will be similar in size and have matched motivation to play and form of play. Neither play time nor proportion of bouts initiated or terminated was correlated with the social rank of the play partner, which suggests that play is not directed toward individuals that may be high-value alliance partners. Maternal intervention in play occurred primarily when infants were<10 weeks old. It was not correlated with the age or social rank of the mother or with the age or social rank of her infant's play partner. Infants played more and terminated a lower proportion of their play bouts in the absence of their mothers than in their presence. Our results are consistent with the hypothesis that the primary function of early play is to enhance physical fitness and to develop coordination and other fighting skills, with minimal risk of injury.     

Vigilance during play in squirrel monkeys

Play by young squirrel monkeys (Saimiri boliviensis) may put them and other troop members at risk for predation because youngsters are noisy, separated from adults, and not vigilant when at play. In a study using separated groups of adults and 1-year-old juveniles caged outdoors, we found that adult female squirrel monkeys become more vigilant during periods of spontaneous play among juveniles. This behavioral response could be obtained with auditory cues (play vocalizations) alone. Five times as much vigilance activity was directed toward an area from which threat or disturbance was likely to come as was directed toward the juveniles themselves. These results suggest both an adaptive, compensatory increase in adult vigilance during play and a function for play vocalizations. Additional functions for play vocalizations remain to be investigated.     

Reciprocity in play,grooming, and proximity in sibling and nonsibling young rhesus monkeys

Play, grooming, and proximity, and the degree to which these were reciprocated between pairs, were studied in immature sibling and nonsibling rhesus monkeys (Macaca mulatta)in four established captive groups over two seasons. “Interaction reciprocity” and “partner reciprocity” were assessed for each dyad for each of the three behaviors. In play, interaction reciprocity was based on the ratio between the play initiations by each dyad member,in grooming on the ratio between the grooming durations by each dyad member, and in proximity on the relative responsibility for proximity maintenance. Two or three most frequent (top) partners for each behavior were found for each individual. If two monkeys were among each other’s top partners, they were said to be reciprocal partners. Monkeys played with nonsiblings as much as with siblings but spent more time grooming and in proximity with siblings than with nonsiblings. Same-age nonsiblings (peers) were more frequent partners than other nonsiblings for each behavior. Siblings’ grooming interactions were more reciprocal than those of nonsiblings. There was no such effect for play and proximity. All-male dyads tended to be more reciprocal in play interactions, and all-female dyads tended to be more reciprocal in grooming interactions. In play, but not in grooming or proximity, the interaction reciprocity of reciprocal partners was higher than that of nonreciprocal dyads. It is argued that the three behaviors have similar roles in infant’s social development but they differ in the expression of this role. Hence the reciprocity patterns vary with the behavior.     

Genetic Color Morphs in the Eastern Mosquitofish Experience Different Social Environments in the Wild and Laboratory

The social environment of an animal is an especially interesting component of its environment because it can be shaped by both genetic and non‐genetic variation among social partners. Indirect genetic effects (IGEs) are those created when genetic variation in social partners contributes to variation in an individual's phenotype; a potentially common form of IGE occurs when the expression of a behavioral phenotype depends on the particular genotypic combination of interacting individuals. Although IGEs can profoundly affect individual‐ and group‐level fitness, population dynamics, and even community structure, understanding their importance is complicated by two inherent challenges: (1) identifying individuals with genetic differences in social interactions that can contribute to IGEs and (2) characterizing natural social interactions that potentially involve IGEs. As a first step toward addressing both these challenges in the same system, we investigated social interactions involving genetically distinct male color morphs in the poeciliid fish Gambusia holbrooki under natural and laboratory conditions. Previous work indicates that melanic (M) and silver (S) males differ in social behavior and in how conspecifics respond to them, suggesting the potential for IGEs. We used a combination of live and video recording of social groups in two natural populations and in the laboratory to determine the potential for IGEs to contribute to behavioral variation in this species. We found that M males had more social partners, and especially more female social partners than did S males, in nature and in the laboratory. These results suggest that both direct and indirect genetic effects have the potential to play a role in the expression and evolution of social behavior in G. holbrooki.     

Cooperation among Norway Rats: The Importance of Visual Cues for Reciprocal Cooperation,and the Role of Coercion

Some animals reciprocate help, but the underlying proximate mechanisms are largely unclear. Norway rats (Rattus norvegicus) have been shown to cooperate in a variant of the iterated prisoner's dilemma paradigm, yet it is unknown which sensory modalities they use. Visual information is often implicitly assumed to play a major role in social interactions, but primarily nocturnal species such as Norway rats may rely on different cues when deciding to reciprocate received help. We used an instrumental cooperative task to compare the test rats' propensity to reciprocate received help between two experimental conditions, with and without visual information exchange between social partners. Our results show that visual information is not required for reciprocal cooperation among social partners because even when it was lacking, test rats provided food significantly earlier to partners that had helped them to obtain food before than to those that had not done so. The mean decision speed did not differ between the two experimental conditions, with or without visual information. Social partners sometimes showed aggressive behaviour towards focal test individuals. When including this in the analyses to assess the possible role of aggression as a trigger of cooperation, aggression received from cooperators apparently reduced the cooperation propensity, whereas aggression received from defectors increased it. Hence, in addition to reciprocity, coercion seems to provide additional means to generate altruistic help in Norway rats.     

Identification of Event-Related Potentials Elicited by Conceptual Mismatch Between Expectations and Self-chosen TV Images

When a voluntary action is followed by an unexpected stimulus, a late positive potential (LPP) with a posterior scalp distribution is elicited in a latency range of 500–700 ms. In the present study, we examined what type of mismatch between expectations and action outcomes was reflected by the LPP. Twelve student volunteers participated in a task simulating choice of TV programs. After choosing one of three options displayed as a cue stimulus, they viewed a second stimulus (still TV image). To manipulate the type of expectation, three kinds of cue conditions were used: thumbnail image condition (three small TV images), category label condition (three words), and no cue condition (three question marks). Over trials, the second stimulus either matched (p = .80) or mismatched (p = .20) the chosen option. As compared to matched TV images, mismatched TV images elicited a larger LPP (500–700 ms) in the thumbnail image and category label conditions. In addition, a larger centroparietal P3 (400–450 ms) was elicited to mismatched TV images in the thumbnail image condition alone. LPP reflects a conceptual mismatch between a category-based expectation and an ensuing action outcome, whereas P3 reflects a perceptual mismatch between an image-based expectation and an action outcome.     

Double Asymmetric Induction During the Addition of (RP)‐Menthyl Phenyl Phosphine Oxide to Chiral Aldimines

P,C‐Stereogenic α‐amino phosphine oxides were prepared from the addition of (R_P)‐menthyl phenyl phosphine oxide to chiral aldimines under neat condition at 80 °C in up to 91:9 dr_C and 99% yields. The diastereoselectivity was mainly induced by chiral phosphorus that showed matched or mismatched induction with (S)‐ or (R)‐aldimines, respectively. Chirality 28:132–135, 2016. © 2015 Wiley Periodicals, Inc.     

Between-partner concordance of vertically transmitted gut microbiota diminishes reproductive output in the dung beetle Onthophagus taurus

In this study, we explored the potential contribution of the gut microbiome to reproductive isolation in tunnelling dung beetles, using Onthophagus taurus (Schreber, 1759) and its sister species O. illyricus (Scopoli, 1763) as a model system (Coleoptera: Scarabaeidae: Scarabaeinae: Onthophagini). Gut microbiota play critical roles in normative development of these beetles, and are vertically inherited via a maternally derived faecal pellet called the pedestal. We first compared the developmental outcomes of individuals reared with pedestals derived from either the same or the sister species (Self and Cross inoculation treatments, respectively). We then crossed the resulting adult O. taurus in three combinations (Self female X Self male; Self female X Cross male; Cross female X Self male). We predicted that if the vertically transmitted gut microbiome plays a role in reproductive isolation by facilitating species recognition, the Self X Self line would have improved reproductive outcomes compared to the lines in which partners had mismatched gut microbiomes. Instead, we found that between-partner concordance of maternally transmitted gut microbiota resulted in fewer offspring, and that this reduction was due to partial pre-copulatory isolation as evidenced by reduced sperm transfer in the Self X Self line. This pattern is consistent either with microbiome-mediated familiarity/kin recognition, or with absence of mate choice in crosses with mismatched microbiomes. We discuss our results in the light of recent research on the influence of extracellular microbial symbionts over insects' mating preferences.     

灵长类社会玩耍的行为模式、影响因素及其功能风险

社会玩耍是指两个或两个以上个体共同参与的一种互作性玩耍行为,个体间的行为彼此适应并相互影响。社会玩耍行为在灵长类物种的社会交往过程中普遍发生,作为未成年个体一种重要的发育行为,其对个体的生存技能和成年后的繁殖成功具有重要影响。灵长类物种的社会玩耍不仅仅表现为追逐、摔跤、跳跃等一些常见行为,部分物种还发展出自己特有的行为。一般而言,社会玩耍在婴儿后期和青少年早期的发生频率最高,然后随着年龄增长直到成年时期,这类行为的平均发生频率将逐渐下降。未成年雄性个体要比同年龄段的雌性个体更喜欢玩耍,但常因物种、研究对象年龄等因素表现不同甚至相反;很多物种的个体喜欢与有亲缘关系的个体玩耍,或者与性别相同、年龄相仿、等级相近的个体玩耍。总之,非人灵长类个体社会玩耍的发育不但受环境参量如食物、场地等的影响,而且还与个体的年龄、性别、等级、亲缘关系等社群因素紧密相关。未成年个体在玩耍过程中,获得了身体机能的快速发育、完善了生存技能、建立了个体间的友好关系、增强了认识自身及适应周围环境的能力,从而为顺利过渡到成年期和履行自己的职能打好基础,但有时却需要承担玩耍过程中受伤甚至死亡的风险。玩耍作为灵长类社会的一种行为文化,对其研究有助于对人类自身行为进化的不断认识,相信这方面的理论将会得到后来者的不断创新和丰富,也期望这方面的理念及经验能被及时运用到保护繁育等实践活动中。     

Selection mosaics differentiate Rhizobium–host plant interactions across different nitrogen environments

The nature and direction of coevolutionary interactions between species is expected to differentiate among distinct environments. Consequently, locally coevolved symbiotic traits would be well matched in similar environments, but mismatched elsewhere. In a classic mutualistic tradeoff, rhizobia provide nitrogen (N) to legume host plants in return for photosynthates. Despite earlier predictions, there is little evidence so far that spatial differences in soil N content mediate the coevolutionary outcome of the legume–Rhizobium mutualism. To test the existence of such selection mosaics, different genotypes of Vicia cracca and Rhizobium leguminosarum originating from spatially and environmentally highly differentiated sites were cross inoculated across different soil N regimes. In accordance with theoretical predictions, we found highly significant effects of genotype by genotype by environment (G× G × E) interactions, on both nodulation and plant growth, even when R. leguminosarum genotypes showed high genetic similarity. Our results show that the trajectory of the coevolutionary interactions between rhizobia and legumes is differentiated across different environments, and that selection mosaics may play an important role in shaping differences in the genetic composition of rhizobial populations.     

Social Play among Juvenile Bighorn Sheep: Structure,Development, and Relationship to Adult Behavior

A 27-mo study of bighorn sheep (Ovis canadensis) was conducted to examine the structure and development of social play among lambs, and to compare that behavior with the behavior of yearlings and adults. Male lambs played more than females and exhibited a larger repertoire. The behavior patterns used by lambs in social play were the same as those used by adults in intrasexual conflict and courtship. However, the repertoire of lambs was more limited than that of adults. Lambs chose partners closest in age to interact with, regardless of sex. Results were consistent with the hypothesis that play serves to develop physical skills and strength.     

Exploring the Social Environment: a Developmental Study of Teasing in Chimpanzees

Long-term data on the occurrence of “teasing” in young chimpanzees living in the Arnhem Zoo chimpanzee colony are presented. They strengthen the hypotheses—presented in earlier papers—concerning the existence of two functional forms of this so-called quasi-aggressive behaviour and provide insight into the way in which they develop. Developmental changes are visible both in the performance of quasi-aggressive behaviour and in the effects evoked by the behaviour. The purpose of the reducing uncertainty type of quasi-aggressive behaviour, performed by male and female youngsters towards adult females, is to obtain more predictable responses. As youngsters grow older, they engage in this behaviour also to gain control over the responses of the target animals. Eventually, the quasi-aggressive behaviour of male youngsters develops into adult-like bluff and attack behaviour the purpose of which is to establish dominance relationships. The investigating authority type of quasi-aggressive behaviour, directed towards adult males, is associated increasingly with the exercise of power by the target males. The youngsters increasingly behave submissively towards the males and direct quasi-aggressive behaviour especially towards the alpha-male at moments when he is bluffing or involved in other conspicuous social interactions. These and other changes in the relationship between adult males and male youngsters are already visible well before the onset of puberty in the youngsters. It is discussed in how far the development of these exploratory aggression types involves social learning processes and how this fits in with current concepts concerning the development of aggressive behaviour.     

Double Stereodifferentiation in the Asymmetric Dihydroxylation of Optically Active Olefins

A study of the stereochemical control on the asymmetric dihydroxylation of the double bond of optically active vinyl epoxides and their derivatives (bromo derivatives, azido derivatives, and vinyl aziridines) was carried out and the obtained results are herein reported. The most interesting results were obtained on trans α,β‐unsaturated epoxy esters, which were successfully converted with a diastereomeric ratio >80% into the corresponding diols using either the matched or the mismatched conditions, depending on the ligand used. Unprotected bromo derivatives and unprotected aziridines did not afford significant results, while for the protected bromo derivatives, azido derivatives, and N‐Boc protected aziridines the matched conditions led to a diastereomeric ratio >95%. Chirality 28:387–393, 2016. © 2016 Wiley Periodicals, Inc.     

The recognition of mismatched base pairs in DNA by DNase I from Ustilago maydis.

Summary The activity of Ustilago maydis DNAse I, an enzyme implicated in genetic recombination, on DNA substrates containing unpaired or mismatched bases, was examined. The enzyme nicked supercoiled PM-2 molecules, converting these to relaxed circular and linear molecules. Discrete double stranded linear fragments smaller than unit length were also observed after digestion at high enzyme concentration. Heteroduplex molecules were constructed using 80 bacteriophage derivatives which contained single base substitutions within the E. coli tRNA ₁ ^tyr gene. Single and double stranded nicking at or near the single mismatched site was observed with three out of the five pairs of heteroduplexes.     

Interplay between various aspects in social relationships of young rhesus monkeys: Dominance,agonistic help,and affiliation

Relationships between group-living primates depend strongly on their position in the group dominance hierarchy and on their relationships with other group members. The influence of various behaviours on social relationships of immature rhesus monkeys (Macaca mulatta) was investigated here. Dominance ranks were established and related to the degree of affiliation in a dyad. Older monkeys were mostly dominant to the younger ones, regardless of kinship. Subordinate monkeys left proximity of their dominant members more often than they were left by them both among siblings and non-siblings, but the effect of dominance rank on the amount of play initiation and grooming in a dyad differed between these two types of dyads. The amount of agonistic help two individuals provided for each other was low among immatures. Nevertheless, pairs of siblings gave help to each other in agonistic conflicts more often than non-siblings, and such help was more often reciprocated between siblings than between non-siblings. Help in agonistic conflicts was positively correlated with the amount of time monkeys spent playing, grooming, or in proximity. Adults tended to interfere less in conflicts of frequent sibling play partners or non-sibling grooming partners. No evidence was found for young monkeys to exchange reciprocally grooming for agonistic help. It is argued that the time monkeys spend interacting with each other in affiliative interactions increases their familiarity and thus promotes close relationships between them. On the whole, young monkeys' relationships, like those between adults, are influenced strongly by their kinship, and position in the dominance hierarchy.     

Efficient mutagenesis method for producing the templates of single nucleotide polymorphisms

DNA templates harboring specific single nucleotide polymorphism (SNP) sites are largely needed as positive controls in practical SNP analysis and in determination of the reliability of newly developed methods in high-throughput screening assays. Here we report a one-step method to produce SNP templates by amplifying a wild-type sequence with primers having single nucleotide mismatches at or near their 3′ ends. A short amplicon harboring an EcoRI site was used to evaluate the feasibility of our strategy. Perfectly matched primers and primers with a single base mismatch occurring from the first base to the sixth base of the EcoRI site were used for primer extension. By using polymerase without a proofreading function, we kept mismatched nucleotides from occurring in extended primer products, as confirmed by EcoRI digestion and sequencing analysis. The strategy of using primers with a single mismatched base and exo- polymerase was shown to be an efficient one-step method for preparing SNP templates, either for application in the development of SNP screening assays or as positive controls in practical SNP assays.     

‘When Birds of a Feather Flock Together’: Synesthetic Correspondences Modulate Audiovisual Integration in Non-Synesthetes

Background

Synesthesia is a condition in which the stimulation of one sense elicits an additional experience, often in a different (i.e., unstimulated) sense. Although only a small proportion of the population is synesthetic, there is growing evidence to suggest that neurocognitively-normal individuals also experience some form of synesthetic association between the stimuli presented to different sensory modalities (i.e., between auditory pitch and visual size, where lower frequency tones are associated with large objects and higher frequency tones with small objects). While previous research has highlighted crossmodal interactions between synesthetically corresponding dimensions, the possible role of synesthetic associations in multisensory integration has not been considered previously.

Methodology

Here we investigate the effects of synesthetic associations by presenting pairs of asynchronous or spatially discrepant visual and auditory stimuli that were either synesthetically matched or mismatched. In a series of three psychophysical experiments, participants reported the relative temporal order of presentation or the relative spatial locations of the two stimuli.

Principal Findings

The reliability of non-synesthetic participants'' estimates of both audiovisual temporal asynchrony and spatial discrepancy were lower for pairs of synesthetically matched as compared to synesthetically mismatched audiovisual stimuli.

Conclusions

Recent studies of multisensory integration have shown that the reduced reliability of perceptual estimates regarding intersensory conflicts constitutes the marker of a stronger coupling between the unisensory signals. Our results therefore indicate a stronger coupling of synesthetically matched vs. mismatched stimuli and provide the first psychophysical evidence that synesthetic congruency can promote multisensory integration. Synesthetic crossmodal correspondences therefore appear to play a crucial (if unacknowledged) role in the multisensory integration of auditory and visual information.     

Sex and age differences in juvenile social priorities in female philopatric,nondespotic blue monkeys

Juveniles should choose social partners on the basis of both current and future utility. Where one sex is philopatric, one expects members of that sex to develop greater and sex‐typical social integration with group‐mates over the juvenile period. Where a partner's position in a dominance hierarchy is not associated with services it can provide, one would not expect juveniles to choose partners based on rank, nor sex differences in rank‐based preferences. We tested these ideas on 39 wild juvenile (3.2–7.4 years) blue monkeys (Cercopithecus mitis stuhlmanni), cercopithecines with strict female philopatry and muted hierarchies. We made focal animal observations over 6 months, and computed observed:expected amounts of proximity time, approaches and grooming given to various social partners. Overall, our results agree with the hypothesis that juvenile blue monkeys target social partners strategically. Spatial proximity, approaches and active grooming showed similar patterns regarding juvenile social preferences. Females were far more sociable than males, groomed more partners, reciprocated grooming more frequently, and preferred—while males avoided—infants as partners. Older juveniles (5–7 years) spent more time than younger juveniles (3–4 years) near others, and older females were especially attracted to infants. Close kin, especially mothers and less consistently adult sisters, were attractive to both male and female juveniles, regardless of age. Both sexes also preferred same‐sex juveniles as social partners while avoiding opposite‐sex peers. Juveniles of both sexes and ages generally neither preferred nor avoided nonmaternal adult females, but all juveniles avoided adult males. Partner's rank had no consistent effect on juveniles' preference, as expected for a species in which dominance plays a weak role. Juveniles' social preferences likely reflect both future and current benefits, including having tolerant adult kin to protect them against predators and conspecifics, same‐sex play partners, and, for females, infants on which to practice mothering skills. Am. J. Primatol. 72:193–205, 2010. © 2009 Wiley‐Liss, Inc.