Estimates of life history parameters in a high latitude, arid-country vervet monkey population.

We present data on life history parameters from a long-term study of vervet monkeys in the Eastern Cape, South Africa. Estimates are presented of age at first conception for females and age at natal dispersal for males, along with the probability of survival to adulthood for infants born during the study, female reproductive life-span, reproductive output (including lifetime reproductive success for a subset of females), and inter-birth interval (IBI) duration. We also assess the effect of maternal age and infant survival on length of IBI.

Using network synchrony to identify drivers of social dynamics.

Social animals frequently show dynamic social network patterns, the consequences of which are felt at the individual and group level. It is often difficult, however, to identify what drivers are responsible for changes in these networks. We suggest that patterns of network synchronization across multiple social groups can be used to better understand the relative contributions of extrinsic and intrinsic drivers.

Experts in action: why we need an embodied social brain hypothesis.

The anthropoid primates are known for their intense sociality and large brain size. The idea that these might be causally related has given rise to a large body of work testing the 'social brain hypothesis'. Here, the emphasis has been placed on the political demands of social life, and the cognitive skills that would enable animals to track the machinations of other minds in metarepresentational ways.

Fevers and the social costs of acute infection in wild vervet monkeys.

Fevers are considered an adaptive response by the host to infection. For gregarious animals, however, fever and the associated sickness behaviors may signal a temporary loss of capacity, offering other group members competitive opportunities. We implanted wild vervet monkeys () with miniature data loggers to obtain continuous measurements of core body temperature.

Formidable females redux: male social integration into female networks and the value of dynamic multilayer networks.

The development of multilayer network techniques is a boon for researchers who wish to understand how different interaction layers might influence each other, and how these in turn might influence group dynamics. Here, we investigate how integration between male and female grooming and aggression interaction networks influences male power trajectories in vervet monkeys . Our previous analyses of this phenomenon used a monolayer approach, and our aim here is to extend these analyses using a dynamic multilayer approach.

Tolerance of muzzle contact underpins the acquisition of foraging information in vervet monkeys (Chlorocebus pygerythrus).

Muzzle contact, where one animal brings its muzzle into close proximity to that of another, has often been hypothesized as a straightforward means of socially mediated food investigation. Using 2,707 observations of muzzle contact occurring across 3 troops of wild vervet monkeys (Chlorocebus pygerythrus), we tested this social learning hypothesis. We first explored the social structuring of muzzle contact by analyzing the characteristics of initiators and receivers.

Field data confirm the ability of a biophysical model to predict wild primate body temperature.

In the face of climate change there is an urgent need to understand how animal performance is affected by environmental conditions. Biophysical models that use principles of heat and mass transfer can be used to explore how an animal's morphology, physiology, and behavior interact with its environment in terms of energy, mass and water balances to affect fitness and performance. We used Niche Mapper™ (NM) to build a vervet monkey (Chlorocebus pygerythrus) biophysical model and tested the model's ability to predict core body temperature (T) variation and thermal stress against T and behavioral data collected from wild vervets in South Africa.

Infrared thermography cannot be used to approximate core body temperature in wild primates.

Understanding the physiological processes that underpin primate performance is key if we are to assess how a primate might respond when navigating new and changing environments. Given the connection between a mammal's ability to thermoregulate and the changing demands of its thermal environment, increasing attention is being devoted to the study of thermoregulatory processes as a means to assess primate performance. Infrared thermography can be used to record the body surface temperatures of free-ranging animals.

Climate induced stress and mortality in vervet monkeys.

As the effects of global climate change become more apparent, animal species will become increasingly affected by extreme climate and its effect on the environment. There is a pressing need to understand animal physiological and behavioural responses to climatic stressors. We used the reactive scope model as a framework to investigate the influence of drought conditions on vervet monkey () behaviour, physiological stress and survival across 2.

Modeling variation in the growth of wild and captive juvenile vervet monkeys in relation to diet and resource availability.

Objectives: To compare longitudinal weight gain in captive and wild juvenile vervet monkeys and conduct an empirical assessment of different mechanistic growth models.

Methods: Weights were collected from two groups of captive monkeys and two consecutive cohorts of wild monkeys until the end of the juvenile period (~800 days). The captive groups were each fed different diets, while the wild groups experienced different ecological conditions.

Gastrointestinal Parasites of Vervet Monkeys () in a High Latitude, Semi-Arid Region of South Africa.

Given a changing climate and large-scale human migration, understanding infectious diseases in wildlife and the factors that drive the spread of these diseases is becoming increasingly important. Owing to the close phylogenetic relationship between nonhuman primates and humans, primate parasites are of particular interest due to the potential for zoonotic disease transmission and for the study of social transmission within gregarious social groups. There is a wide range of social and environmental factors that influence the prevalence and transmission of pathogens, and identifying these, and their effects, is crucial to understanding the population-level consequences of climate change for animals that live in obligate social groups.

Ultrasonic aspiration in neurosurgery: comparative analysis of complications and outcome for three commonly used models.

Introduction: Ultrasonic aspiration (UA) devices are commonly used for resecting intracranial tumors, as they allow for internal debulking of large tumors, hereby avoiding damage to adjacent brain tissue during the dissection. Little is known about their comparative safety profiles.

Methods And Materials: We analyzed data from a prospective patient registry.

Safety of resident training in the microsurgical resection of intracranial tumors: Data from a prospective registry of complications and outcome.

The aim of the present study was to assess the safety of microsurgical resection of intracranial tumors performed by supervised neurosurgical residents. We analyzed prospectively collected data from our institutional patient registry and dichotomized between procedures performed by supervised neurosurgery residents (defined as teaching procedures) or board-certified faculty neurosurgeons (defined as non-teaching procedures). The primary endpoint was morbidity at discharge, defined as a postoperative decrease of ≥10 points on the Karnofsky Performance Scale (KPS).

Functional social structure in baboons: Modeling interactions between social and environmental structure in group-level foraging.

In mobile social groups, cohesion is thought to be driven by patterns of attraction at both the individual and group level. In long-lived species with high group stability and repeated interactions, such as baboons, individual-to-individual attractions have the potential to play a large role in group cohesion and overall movement patterns. In previous work, we found that the patterning of inter-individual attraction gave rise to an emergent group-level structure, whereby a core of more influential, inter-dependent individuals exerted a unidirectional influence on the movements of peripheral animals.

Assessment of Male Reproductive Skew via Highly Polymorphic STR Markers in Wild Vervet Monkeys, Chlorocebus pygerythrus.

Male reproductive strategies have been well studied in primate species where the ability of males to monopolize reproductive access is high. Less is known about species where males cannot monopolize mating access. Vervet monkeys (Chlorocebus pygerythrus) are interesting in this regard as female codominance reduces the potential for male monopolization.

Network integration and limits to social inheritance in vervet monkeys.

Social networks can be adaptive for members and a recent model (Ilany and Akçay 2016 , 12084 (doi:10.1038/ncomms12084)) has demonstrated that network structure can be maintained by a simple process of social inheritance. Here, we ask how juvenile vervet monkeys integrate into their adult grooming networks, using the model to test whether observed grooming patterns replicate network structure.

Faecal glucocorticoid metabolite monitoring as a measure of physiological stress in captive and wild vervet monkeys.

The development of non-invasive techniques to analyse physiological stress in mammalian species has revolutionised field-based endocrinology. However, careful validation of the methods used to determine faecal glucocorticoid metabolite (fGCM) and other hormone concentrations are required on a species- and sex-specific basis. In this study, we performed an adrenocorticotropic hormone (ACTH) stimulation test on four (two male and two female) captive vervet monkeys (Chlorocebus pygerythrus) to determine the most appropriate enzyme immunoassay (EIA) from a suite of available EIAs.

Individual-level movement bias leads to the formation of higher-order social structure in a mobile group of baboons.

In mobile social groups, influence patterns driving group movement can vary between democratic and despotic. The arrival at any single pattern of influence is thought to be underpinned by both environmental factors and group composition. To identify the specific patterns of influence driving travel decision-making in a chacma baboon troop, we used spatially explicit data to extract patterns of individual movement bias.

Thermal consequences of increased pelt loft infer an additional utilitarian function for grooming.

A strong case has been made that the primary function of grooming is hygienic. Nevertheless, its persistence in the absence of hygienic demand, and its obvious tactical importance to members of primate groups, underpins the view that grooming has become uncoupled from its utilitarian objectives and is now principally of social benefit. We identify improved thermoregulatory function as a previously unexplored benefit of grooming and so broaden our understanding of the utilitarian function of this behavior.

Taking the aggravation out of data aggregation: A conceptual guide to dealing with statistical issues related to the pooling of individual-level observational data.

Field data often include multiple observations taken from the same individual. In order to avoid pseudoreplication, it is commonplace to aggregate data, generating a mean score per individual, and then using these aggregated data in subsequent analyses. Aggregation, however, can generate problems of its own.

Social integration confers thermal benefits in a gregarious primate.

Sociality has been shown to have adaptive value for gregarious species, with more socially integrated animals within groups experiencing higher reproductive success and longevity. The value of social integration is often suggested to derive from an improved ability to deal with social stress within a group; other potential stressors have received less attention. We investigated the relationship between environmental temperature, an important non-social stressor, and social integration in wild female vervet monkeys (Chlorocebus pygerythrus), using implanted data loggers to obtain direct measures of core body temperature.

Behavioral flexibility of vervet monkeys in response to climatic and social variability.

Responses to environmental variability sheds light on how individuals are able to survive in a particular habitat and provides an indication of the scope and limits of its niche. To understand whether climate has a direct impact on activity, and determine whether vervet monkeys have the behavioral flexibility to respond to environmental change, we examined whether the amount of time spent resting and feeding in the nonmating and mating seasons were predicted by the thermal and energetic constraints of ambient temperature. Our results show that high temperatures during the nonmating season were associated with an increase in time spent resting, at the expense of feeding.

Ontogenetic scaling of fore- and hind limb posture in wild chacma baboons (Papio hamadryas ursinus).

Large-scale interspecific studies of mammals ranging between 0.04-280 kg have shown that larger animals walk with more extended limb joints. Within a taxon or clade, however, the relationship between body size and joint posture is less straightforward.

Social coordination: patience is a virtue for vervet monkeys.

Free-ranging vervet monkeys can solve a complex, multi-player coordination problem, learning to remain outside a 'forbidden circle' imposed by one member of the troop, in the absence of any social learning, communication, or policing by more dominant animals.