You Mate, I Mate: Macaque Females Synchronize Sex not Cycles

Extended female sexuality in species living in multimale-multifemale groups appears to enhance benefits from multiple males. Mating with many males, however, requires a low female monopolizability, which is affected by the spatiotemporal distribution of receptive females. Ovarian cycle synchrony potentially promotes overlapping receptivity if fertile and receptive periods are tightly linked. In primates, however, mating is often decoupled from hormonal control, hence reducing the need for synchronizing ovarian events. Here, we test the alternative hypothesis that females behaviorally coordinate their receptivity while simultaneously investigating ovarian cycle synchrony in wild, seasonal Assamese macaques (Macaca assamensis), a promiscuous species with extremely extended female sexuality. Using fecal hormone analysis to assess ovarian activity we show that fertile phases are randomly distributed, and that dyadic spatial proximity does not affect their distribution. We present evidence for mating synchrony, i.e., the occurrence of the females' receptivity was significantly associated with the proportion of other females mating on a given day. Our results suggest social facilitation of mating synchrony, which explains (i) the high number of simultaneously receptive females, and (ii) the low male mating skew in this species. Active mating synchronization may serve to enhance the benefits of extended female sexuality, and may proximately explain its patterning and maintenance

Chorusing, synchrony, and the evolutionary functions of rhythm

A central goal of biomusicology is to understand the biological basis of human musicality. One approach to this problem has been to compare core components of human musicality (relative pitch perception, entrainment, etc.) with similar capacities in other animal species. Here we extend and clarify this comparative approach with respect to rhythm. First, whereas most comparisons between human music and animal acoustic behavior have focused on spectral properties (melody and harmony), we argue for the central importance of temporal properties, and propose that this domain is ripe for further comparative research. Second, whereas most rhythm research in non-human animals has examined animal timing in isolation, we consider how chorusing dynamics can shape individual timing, as in human music and dance, arguing that group behavior is key to understanding the adaptive functions of rhythm. To illustrate the interdependence between individual and chorusing dynamics, we present a computational model of chorusing agents relating individual call timing with synchronous group behavior. Third, we distinguish and clarify mechanistic and functional explanations of rhythmic phenomena, often conflated in the literature, arguing that this distinction is key for understanding the evolution of musicality. Fourth, we expand biomusicological discussions beyond the species typically considered, providing an overview of chorusing and rhythmic behavior across a broad range of taxa (orthopterans, fireflies, frogs, birds, and primates). Finally, we propose an “Evolving Signal Timing” hypothesis, suggesting that similarities between timing abilities in biological species will be based on comparable chorusing behaviors. We conclude that the comparative study of chorusing species can provide important insights into the adaptive function(s) of rhythmic behavior in our “proto-musical” primate ancestors, and thus inform our understanding of the biology and evolution of rhythm in human music and language

Music and dance as a coalition signaling system

Evidence suggests that humans have neurological specializations for music processing, but a compelling adaptationist account of music and dance is lacking. The sexual selection hypothesis cannot easily account for the widespread performance of music and dance in groups (especially synchronized performances), and the social bonding hypothesis has severe theoretical difficulties. Humans are unique among the primates in their ability to form cooperative alliances between groups in the absence of consanguineal ties. We propose that this unique form of social organization is predicated on music and dance. Music and dance may have evolved as a coalition signaling system that could, among other things, credibly communicate coalition quality, thus permitting meaningful cooperative relationships between groups. This capability may have evolved from coordinated territorial defense signals that are common in many social species, including chimpanzees. We present a study in which manipulation of music synchrony significantly altered subjects’ perceptions of music quality, and in which subjects’ perceptions of music quality were correlated with their perceptions of coalition quality, supporting our hypothesis. Our hypothesis also has implications for the evolution of psychological mechanisms underlying cultural production in other domains such as food preparation, clothing and body decoration, storytelling and ritual, and tools and other artifacts

Coordination Matters : Interpersonal Synchrony Influences Collaborative Problem-Solving

The authors thank Martha von Werthern and Caitlin Taylor for their assistance with data collection, Cathy Macpherson for her assistance with the preparation of the manuscript, and Mike Richardson, Alex Paxton, and Rick Dale for providing MATLAB code to assist with data analysis. The research was funded by the British Academy (SG131613).Peer reviewedPublisher PD

The dancing queen:explanatory mechanisms of the 'feel-good effect' in dance

Dance is a social, creative form of human activity impacting on wellbeing through emotional involvement in active or passive participation at all levels of mastery. Dance as a physical activity can potentially improve health physiologically, psychologically, and socially. Despite a recent surge in dance-related research, the authors believe that this area of human behaviour is still relatively unexplored. Here, therefore, they examine possible mechanisms that may contribute to the ‘feel-good effect’ of dance participation by emphasizing its positive as well as its potentially detrimental effects, taking the physical activity literature as a starting point. They address biochemical, brain neurotransmitters, cognitive–neuroscientific, and psychological mechanisms that are thought to explain the impact of physical activity in wellbeing, and discuss functional and structural brain changes that are linked to participation in dance. They conclude by highlighting the need to increase research to better recognize the potential risks and benefits of dance in improving health and wellbeing

A Mathematical Model for the Dynamics and Synchronization of Cows

We formulate a mathematical model for daily activities of a cow (eating, lying down, and standing) in terms of a piecewise affine dynamical system. We analyze the properties of this bovine dynamical system representing the single animal and develop an exact integrative form as a discrete-time mapping. We then couple multiple cow "oscillators" together to study synchrony and cooperation in cattle herds. We comment on the relevant biology and discuss extensions of our model. With this abstract approach, we not only investigate equations with interesting dynamics but also develop interesting biological predictions. In particular, our model illustrates that it is possible for cows to synchronize \emph{less} when the coupling is increased.Comment: to appear in Physica

The effects of dominance on leadership and energetic gain: a dynamic game between pairs of social foragers

Although social behaviour can bring many benefits to an individual, there are also costs that may be incurred whenever the members of a social group interact. The formation of dominance hierarchies could offer a means of reducing some of the costs of social interaction, but individuals within the hierarchy may end up paying differing costs dependent upon their position within the hierarchy. These differing interaction costs may therefore influence the behaviour of the group, as subordinate individuals may experience very different benefits and costs to dominants when the group is conducting a given behaviour. Here, a state-dependent dynamic game is described which considers a pair of social foragers where there is a set dominance relationship within the pair. The model considers the case where the subordinate member of the pair pays an interference cost when it and the dominant individual conduct specific pairs of behaviours together. The model demonstrates that if the subordinate individual pays these energetic costs when it interacts with the dominant individual, this has effects upon the behaviour of both subordinate and the dominant individuals. Including interaction costs increases the amount of foraging behaviour both individuals conduct, with the behaviour of the pair being driven by the subordinate individual. The subordinate will tend to be the lighter individual for longer periods of time when interaction costs are imposed. This supports earlier suggestions that lighter individuals should act as the decision-maker within the pair, giving leadership-like behaviours that are based upon energetic state. Pre-existing properties of individuals such as their dominance will be less important for determining which individual makes the decisions for the pair. This suggests that, even with strict behavioural hierarchies, identifying which individual is the dominant one is not sufficient for identifying which one is the leader

Transient Analysis for Music and Moving Images: Consideration for Television Advertising

In audiovisual composition, coupling montage moving images with music is common practice. Interpretation of the effect on an audioviewer's consequent interpretation of the composition is discursive and unquantified. Meth-odology for evaluating the audiovisual multimodal inter-activity is proposed, developing an analysis procedure via the study of modality interdependent transient structures, explained as forming the foundation of perception via the concept of Basic Exposure response to the stimulus. The research has implications for analysis of all audiovisual media, with practical implications in television advertis-ing as a discrete typology of target driven audiovisual presentation. Examples from contemporary advertising are used to explore typical transient interaction patterns and the consequences of which are discussed from the practical viewpoint of the audiovisual composer