Search Our Scientific Publications & Authors

Am J Primatol 2019 Apr 18:e22977. Epub 2019 Apr 18.

Department of Computer Science and Engineering, University of Minnesota, Minneapolis, Minnesota.

The mammalian order primates contains wide species diversity. Members of the subfamily Colobinae are unique amongst extant primates in that their gastrointestinal systems more closely resemble those of ruminants than other members of the primate order. In the growing literature surrounding nonhuman primate microbiomes, analysis of microbial communities has been limited to the hindgut, since few studies have captured data on other gut sites, including the foregut of colobine primates. Read More

Am J Primatol 2019 Apr 15:e22973. Epub 2019 Apr 15.

Department of Psychology, Georgia State University, Atlanta, Georgia.

Comparative approaches to experimental economics have shed light on the evolution of social decision-making across a range of primate species, including humans. Here we replicate our previous work looking at six pairs of capuchin monkeys' (Sapajus [Cebus] apella) responses to scenarios requiring both coordination (Assurance Game) and anti-coordination (Hawk-Dove Game). This then provides a foundation for assessing their responses to two additional games, one with a scenario of beneficial cooperation with a temptation to defect (Prisoner's Dilemma) and one with an environment requiring changing strategies within short temporal proximity (Alternating Economic Game). Read More

Am J Primatol 2019 Apr 2:e22970. Epub 2019 Apr 2.

Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana.

To date, most insights into the processes shaping vertebrate gut microbiomes have emerged from studies with cross-sectional designs. While this approach has been valuable, emerging time series analyses on vertebrate gut microbiomes show that gut microbial composition can change rapidly from 1 day to the next, with consequences for host physical functioning, health, and fitness. Hence, the next frontier of microbiome research will require longitudinal perspectives. Read More

Am J Primatol 2019 Apr 2:e22969. Epub 2019 Apr 2.

Center for Microbial Pathogenesis, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio.

The gastrointestinal microbiome is recognized as a critical component in host immune function, physiology, and behavior. Early life experiences that alter diet and social contact also influence these outcomes. Despite the growing number of studies in this area, no studies to date have examined the contribution of early life experiences on the gut microbiome in infants across development. Read More

Am J Primatol 2019 Apr 2:e22971. Epub 2019 Apr 2.

School of Human Sciences, The University of Western Australia, Crawley, Western Australia, Australia.

Almost all primates experience seasonal fluctuations in the availability of key food sources. However, the degree to which this fluctuation impacts foraging behavior varies considerably. Eastern chimpanzees (Pan troglodytes schweinfurthii) in Nyungwe National Park, Rwanda, live in a montane forest environment characterized by lower primary productivity and resource diversity than low-elevation forests. Read More

Am J Primatol 2019 Apr 1:e22974. Epub 2019 Apr 1.

Duke University Program in Ecology, Duke University, Durham, North Carolina.

Research on animal microbiomes is increasingly aimed at determining the evolutionary and ecological factors that govern host-microbiome dynamics, which are invariably intertwined and potentially synergistic. We present three empirical studies related to this topic, each of which relies on the diversity of Malagasy lemurs (representing a total of 19 species) and the comparative approach applied across scales of analysis. In Study 1, we compare gut microbial membership across 14 species in the wild to test the relative importance of host phylogeny and feeding strategy in mediating microbiome structure. Read More

Am J Primatol 2019 Mar 28:e22967. Epub 2019 Mar 28.

School of Biological Sciences, Royal Holloway, University of London, Egham, Surrey, England.

Although potentially beneficial in terms of raising awareness and conservation funding, tourist visitation of wild primates can have negative impacts on visited groups. Tourism-generated noise is a relatively understudied facet of ecotourism research, and the effects of tourist-generated speech on free-ranging, wild primates has never been explored previously. This study investigates the behavioral responses of 10 groups of pygmy marmosets (Cebuella pygmaea) to human speech. Read More

Am J Primatol 2019 Mar 28:e22966. Epub 2019 Mar 28.

Institute of Ecology and Evolution, University of Oregon, Eugene, Oregon.

Host behavior and social factors have increasingly been implicated in structuring the composition of gut microbial communities. In social animals, distinct microbial communities characterize different social groups across a variety of taxa, although little longitudinal research has been conducted that demonstrates how this divergence occurs. Our study addresses this question by characterizing the gut microbial composition of an African Old World monkey, the black-and-white colobus (Colobus vellerosus), before and after a social group fission event. Read More

Am J Primatol 2019 Mar 28:e22968. Epub 2019 Mar 28.

Graduate Program in Evolution, Ecology, and Behavior, University at Buffalo, Buffalo, New York.

Primatologists have long focused on grooming exchanges to examine aspects of social relationships, co-operation, and social cognition. One particular interest is the extent to which reciprocating grooming partners time match, and the time frame over which they do so. Conclusions about time matching vary across species. Read More

Am J Primatol 2019 Mar 26:e22972. Epub 2019 Mar 26.

Department of Anthropology, University of Toronto, Toronto, Ontario, Canada.

We used species-area relationships (SARs) to investigate the effects of habitat loss on lemur biogeography. We measured species richness via visual surveys on line transects within 42 fragments of dry deciduous forest at the Ambanjabe field site in Ankarafantsika National Park, Madagascar. We measured human disturbance and habitat characteristics within 38 of the 42 fragments. Read More

Am J Primatol 2019 Mar 8:e22965. Epub 2019 Mar 8.

Charles Perkins Centre, University of Sydney, Sydney, New South Wales, Australia.

Recent advances in niche theory have stressed the importance of understanding dietary generalism at multiple levels, including the range of habitat and foods exploited by a species, foods exploited within populations, and patterns of nutrient intake. Here we apply this framework to examine the dietary strategy of the Macaca mulatta, a primate species that is second only to humans in their breadth of geographical distribution, and occupy diverse ecological habitats from cold temperate to tropical latitudes. A recent study showed that the Taihangshan subspecies ( M. Read More

Am J Primatol 2019 Mar 4;81(3):e22961. Epub 2019 Mar 4.

Instituto Pri-Matas para a Conservação da Biodiversidade, Belo Horizonte, MG, Brazil.

The world currently faces severe biodiversity losses caused by anthropogenic activities such as deforestation, pollution, the introduction of exotic species, habitat fragmentation, and climate changes. Disease ecology in altered environments is still poorly understood. The golden-headed lion tamarin (GHLT, Leontopithecus chrysomelas) is an endangered species that became invasive in an urban park in Niterói, Rio de Janeiro, Brazil. Read More

Am J Primatol 2019 Mar 27;81(3):e22962. Epub 2019 Feb 27.

Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.

The extension of distance sampling methods to accommodate observations from camera traps has recently enhanced the potential to remotely monitor multiple species without the need of additional data collection (sign production and decay rates) or individual identification. However, the method requires that the proportion of time is quantifiable when animals can be detected by the cameras. This can be problematic, for instance, when animals spend time above the ground, which is the case for most primates. Read More

Am J Primatol 2019 Mar 27;81(3):e22958. Epub 2019 Feb 27.

Research Laboratory for Archaeology and the History of Art, Oxford University, Oxford, UK.

Bearded capuchin monkeys crack nuts with naturally varying stone hammers, suggesting they may tune their grips and muscular forces to each stone. If so, they might use discrete actions on a stone before lifting and striking, and they would likely use these actions more frequently when the stone is larger and/or less familiar and/or when first initiating striking. We examined the behavior of (a) four monkeys (all proficient at cracking nuts) with two larger (1 kg) and two smaller (0. Read More

Am J Primatol 2019 Mar 27;81(3):e22959. Epub 2019 Feb 27.

Laboratório de Ciências Ambientais, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense, Campos dos Goytacazes, Rio de Janeiro, Brazil.

The study of the social drivers of animal dispersal is key to understanding the evolution of social systems. Among the social drivers of natal emigration, the conspecific attraction, aggressive eviction, and reduced social integration hypotheses predict that sexually mature individuals who receive more aggressive behavior and are engaged in less affiliative interactions are more likely to disperse. Few reports have explored these proximate factors affecting emigration in cooperatively breeding species, particularly of Neotropical primates. Read More

Am J Primatol 2019 Feb 27:e22964. Epub 2019 Feb 27.

Department of Anthropology, Program in Ecology, Evolution, and Conservation Biology, University of Illinois, Urbana, Illinois.

Models of primate sociality focus on the costs and benefits of group living and how factors such as rank, feeding competition, alliance formation, and cooperative behavior shape within-group social relationships. We conducted a series of controlled field experiments designed to investigate how resource distribution (one or three of four reward platforms) and amount of food on a reward platform affected foraging strategies and individual feeding success in four groups of wild common marmosets (Callithrix jacchus) living in the Caatinga of northeastern Brazil. At our field site, common marmoset groups are characterized by a single breeding female who can produce twin litters twice per year, strong social cohesion, and cooperative infant care provided principally by several adult male helpers. Read More

Am J Primatol 2019 Mar 26;81(3):e22963. Epub 2019 Feb 26.

Laboratory of Theoretical and Applied Ethology, Department of Biology, Federal Rural University of Pernambuco, Recife, Brazil.

Most species of New World primates have an unusual color vision pattern that can affect an individual's ability to detect food. Whereas males can only be dichromatic, females can be either dichromatic or trichromatic. Trichromats are expected to have an advantage in detecting conspicuous food whereas dichromats should be better at locating cryptic resources. Read More

Am J Primatol 2019 Feb 25;81(2):e22960. Epub 2019 Feb 25.

Department of Science and Mathematics, Texas A&M University San Antonio, San Antonio, Texas.

The gut microbiome is known to play a significant role in human health but its role in aging remains unclear. The objective of this study was to compare the gut microbiome composition between young adult and geriatric non-human primates (marmosets) as a model of human health and disease. Stool samples were collected from geriatric (8+ years) and young adult males (2-5 years). Read More

Am J Primatol 2019 Feb 18;81(2):e22956. Epub 2019 Feb 18.

Department of Pharmacology, Center of Research in Advance Studies, Mexico City, Mexico.

Microglia are cells that protect brain tissue from invading agents and toxic substances, first by releasing pro-inflammatory cytokines, and thereafter by clearing tissue by phagocytosis. Microglia express ferritin, a protein with ferroxidase activity capable of storing iron, a metal that accumulates in brain during aging. Increasing evidence suggests that ferritin plays an important role in inflammation. Read More

Am J Primatol 2019 Mar 18;81(3):e22957. Epub 2019 Feb 18.

Conservation Ecology Program, King Mongkut's University of Technology Thonburi, Bangkok, Thailand.

Primate survival in disturbed forests can be governed by a complex of forest variables. For nocturnal arboreal primates, determining these ecological features is notoriously difficult but is critically important for their conservation. Here we assessed the effects of forest type, food availability, human disturbance, and forest structure on the nocturnal Bengal slow loris (Nycticebus bengalensis) in Sakaerat Biosphere, north-east Thailand, a small disturbed fragment containing dry evergreen, dry dipterocarp, and plantation forests. Read More

Am J Primatol 2019 Mar 18;81(3):e22955. Epub 2019 Feb 18.

Department of Genetics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.

The phylogenetic position of owl monkeys, grouped in the genus Aotus, has been a controversial issue for understanding Neotropical primate evolution. Explanations of the difficult phylogenetic assignment of owl monkeys have been elusive, frequently relying on insufficient data (stochastic error) or scenarios of rapid speciation (adaptive radiation) events. Using a coalescent-based approach, we explored the population-level mechanisms likely explaining these topological discrepancies. Read More

Am J Primatol 2019 Feb 6;81(2):e22912. Epub 2019 Feb 6.

Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, Texas.

The life history of the common marmoset (Callithrix jacchus) points to this species as a premiere nonhuman primate aging model. In order to take advantage of these features, we require an expanded and refined understanding of aging in this species. The papers in this special issue move this field forward substantially by providing exciting new findings about the aging of the common marmoset and the potential this species offers for revealing aging's secrets and improving the lives of aging humans. Read More

Am J Primatol 2019 Mar 1;81(3):e22954. Epub 2019 Feb 1.

School of Natural Sciences and Psychology, Liverpool John Moores University, Liverpool, UK.

Studying the communication systems of primates can provide insights into the evolutionary origins of human language. Some theories propose that language evolved to help meet the demands of managing complex social relationships. Examining the associations between sociality and communication in the great apes can help to identify the specific selection pressures that may have been important for language evolution. Read More

Am J Primatol 2019 Mar 21;81(3):e22950. Epub 2019 Jan 21.

Graduate Group in Animal Behavior, University of California, Davis, California.

In many primates, the acoustic properties of alarm calls can provide information on the level of perceived predatory threat as well as influence the antipredator behavior of nearby conspecifics. The present study examined the harmonics-to-noise ratio (tonality of spectral structure) of alarm calls emitted by white-faced capuchin monkeys (Cebus capucinus) in trees directed at photographic models of a boa constrictor, neotropical rattlesnake, scorpion eater snake, and white snake-shaped control presented on the ground. The average and peak harmonics-to-noise ratios of initial alarm calls by infants, juveniles, and adults and those of nearby second callers were analyzed using PRAAT software. Read More

Am J Primatol 2019 Mar 21;81(3):e22953. Epub 2019 Jan 21.

School of Natural Sciences and Psychology, Liverpool John Moores University, Liverpool, UK.

The reduction in dental size and mandibular robusticity is regarded as a major trend in human evolution, traditionally considered the result of the peculiar extra-oral food processing skills of Homo. The use of stone tools and fire would have allowed our ancestors to chew softer food in smaller bite size, thus relaxing the selective pressures to keep a large dentition and a robust lower jaw. This perspective assumes that differences in dental size and mandibular robusticity in hominins represent functional dissimilarities. Read More

Am J Primatol 2019 Feb 21;81(2):e22952. Epub 2019 Jan 21.

Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, Texas.

The development of the marmoset as a translational model for healthspan and lifespan studies relies on the characterization of health parameters in young and geriatric marmosets. This cross-sectional study examined health phenotypes in marmosets for five domains of interest for human health and aging: mobility, cognition, metabolism, homeostasis, and immune function. Geriatric marmosets were found to have significant executive function impairment when compared to young animals. Read More

Am J Primatol 2019 Jan 21;81(1):e22951. Epub 2019 Jan 21.

Department of Biology, Chemistry and Forensic Science, University of Wolverhampton, City Campus South, Wolverhampton, United Kingdom.

Primate chemical communication remains underappreciated, as primates are considered to rely on other sensory modalities. However, various lines of evidence suggest that olfaction plays an important role in primate societies, including the conspicuous scent-marking behavior of many strepsirrhines and callitrichines. Although lemurs typically show scent-marking, little is known about this behavior in red-ruffed lemurs (Varecia variegata rubra). Read More

Am J Primatol 2019 Jan 8;81(1):e22948. Epub 2019 Jan 8.

California National Primate Research Center, University of California Davis, Davis, California.

Diarrhea with secondary decompensation is the main cause of morbidity and mortality in captive young rhesus macaque (Macaca mulatta) colonies. Approximately 25% of diarrhea cases with secondary decompensation are considered to be idiopathic chronic diarrhea. The purpose of this study was to investigate the suspected but not systematically examined association between rotavirus infection and diarrhea with secondary decompensation among young rhesus macaques at the California National Primate Research Center (CNPRC). Read More

Am J Primatol 2019 Feb 8;81(2):e22949. Epub 2019 Jan 8.

Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, Texas.

Executive control is a higher-level cognitive function that involves a range of different processes that are involved in the planning, coordination, execution, and inhibition of responses. Many of the processes associated with executive control, such as response inhibition and mental flexibility, decline with age. Degeneration of white matter architecture is considered to be the one of the key factors underlying cognitive decline associated with aging. Read More

Am J Primatol 2019 Jan 8;81(1):e22947. Epub 2019 Jan 8.

The University of Texas MD Anderson Cancer Center, Michale E. Keeling Center for Comparative Medicine and Research, Bastrop, Texas.

The National Institutes of Health and the Association of Zoos and Aquariums recommend that captive chimpanzees be housed in multi-male, multi-female, age-diverse groups of no less than seven individuals. These recommendations are rooted in the idea that captive chimpanzee groups should be modeled after free-ranging, wild, fission-fusion chimpanzee societies. However, captive chimpanzees do not face the environmental pressures faced by wild chimpanzees, including food scarcity, inter-group competition, and predation. Read More

Am J Primatol 2019 Jan 3;81(1):e22940. Epub 2019 Jan 3.

Institute of Zoology, Zoological Society of London, London, UK.

We develop a time budget model for the hylobatid family with the aim of assessing the extent to which their contemporary and historical biogeographic distributions might be explained by ecological constraints. The model uses local climate to predict time budgets, and from this the limiting size of social group that animals could manage at a given location. The model predicts maximum group sizes that vary between 3 and 15 within the taxon's current distribution, indicating that the combination of their dietary and locomotor styles with the kinds of habitats they inhabit radically constrain group size. Read More

Am J Primatol 2019 Jan 3;81(1):e22945. Epub 2019 Jan 3.

Institut für Ur- und Frühgeschichte und Archäologie des Mittelalters, Eberhard Karls Universität Tübingen, Tuebingen, Germany.

The diversity of great ape diets requires behavioral flexibility. Consequently, the exploration of potentially novel food sources is supposedly beneficial, but simultaneously, apes show high neophobia to prevent harmful and poisonous food intake. Social information, such as presence of group members or observations of non-naïve, experienced individuals have been demonstrated to affect the acceptance of novel food items in primates. Read More

Am J Primatol 2019 Jan 3:e22941. Epub 2019 Jan 3.

Chimp Haven, Keithville, Louisiana.

Am J Primatol 2018 Dec;80(S1):e22942

Am J Primatol 2019 Jan 3;81(1):e22943. Epub 2019 Jan 3.

Department of Anthropology, Stony Brook University, Stony Brook, New York.

Poor maternal condition during gestation is commonly associated with impaired fetal growth in humans and other animals. Although elevated maternal glucocorticoids (GCs) are often implicated as the mechanism of intrauterine growth stunting, the direct contribution of maternal GCs remains unclear because enzymatic conversion of GCs at the placenta may limit the ability of maternal hormones to reach the fetus. Further, because previous studies on gestational stress have often employed synthetic GCs, which cross the placenta unobstructed, it remains unknown whether naturalistic endogenous GC elevations will have similar effects. Read More

Am J Primatol 2019 Feb 26;81(2):e22931. Epub 2018 Dec 26.

Cerebral Microcirculation Section, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland.

Research with non-human primates (NHP) has been essential and effective in increasing our ability to find cures for a large number of diseases that cause human suffering and death. Extending the availability and use of genetic engineering techniques to NHP will allow the creation and study of NHP models of human disease, as well as broaden our understanding of neural circuits in the primate brain. With the recent development of efficient genetic engineering techniques that can be used for NHP, there's increased hope that NHP will significantly accelerate our understanding of the etiology of human neurological and neuropsychiatric disorders. Read More

Am J Primatol 2019 Feb 26;81(2):e22944. Epub 2018 Dec 26.

Division of Pulmonary Allergy and Critical Care, Department of Medicine, Emory University, Atlanta, Georgia.

Recently, the common marmoset has been proposed as a non-human primate model of aging. Their short lifespan coupled with pathologies that are similar to humans make them an ideal model to understand the genetic, metabolic, and environmental factors that influence aging and longevity. However, many of the underlying physiological changes that occur with age in the marmoset are unknown. Read More

Am J Primatol 2018 Dec;80(12):e22936

College of Environmental Science and Engineering, China West Normal University, Nanchong, Sichuan, China.

For non-human primates to optimize their survival chances, sleeping site selection is crucial as they spend much of their time sleeping. We studied sleeping site and tree selection by a group of wild Sichuan snub-nosed monkeys (Rhinopithecus roxellana) in the temperate forests of Baihe Nature Reserve, Sichuan, China, to assess if certain site and tree characteristics were selected. We identified a total of 39 sleeping sites and 111 sleeping trees over a period of 1 year. Read More

Am J Primatol 2018 Dec;80(12):e22932

Department of Anthropology, University of California, Davis, California.

Predation is widely recognized as an important selective pressure on prey animals such as baboons (Papio spp.), which face high leopard (Panthera pardus) predation risk, particularly at night. Baboons regularly sleep on cliff faces and in trees at night, ostensibly to avoid such predators. Read More

Am J Primatol 2018 Dec;80(12):e22933

Department of Animal Physiology, Institute for Zoology, University of Tübingen, Tübingen, Germany.

Diel activity rhythms in mammals are regulated by an endogenous (circadian) timing system which is synchronized by environmental 24-hr periodicities called zeitgebers. Additional direct responses to stochastic environmental factors ensure the fine-tuning to the actual situation and may mask the circadian time course. Following an observational study on behavioral effects of visitor activities in a group of spider monkeys (Ateles geoffroyi) kept free-ranging on a small island of Lake Catemaco, Veracruz, Mexico, we analyzed the effect of weekly varying numbers of visiting tourist boats on the monkeys' diel activity rhythm. Read More

Am J Primatol 2018 Dec;80(12):e22935

Department of Neuroscience, Washington University School of Medicine, Saint Louis, Missouri.

Vitamin D adequacy is essential for multiple physiologic processes. With limited exposure to sunlight for vitamin D synthesis, captive primates are supplemented with vitamin D (cholecalciferol). Vitamin D metabolite data from wild primates living indigenously could suggest optimum levels. Read More

Am J Primatol 2018 Dec 4;80(12):e22939. Epub 2018 Dec 4.

California National Primate Research Center, Davis, California.

Early life experiences reorganize the brain and behavior of the developing infant, often with lifelong consequences. There is perhaps no more potent developmental influence than the quality of parental care: it is an experience common to all mammals, and its effects have been observed across species. The effects of parental care can be particularly difficult to abolish, as levels of care are often perpetuated across generations. Read More

Am J Primatol 2018 Dec 29;80(12):e22937. Epub 2018 Nov 29.

Department of Psychology, Oakland University, Rochester, Michigan.

Historically, the empirical study of the role of sperm competition in the evolution of sexual traits has been problematic through an enforced reliance on indirect proxy measures. Recently, however, a procedure was developed that uses paternity data to measure sperm competition level directly in terms of males/conception (i.e. Read More

Am J Primatol 2018 Dec 27;80(12):e22938. Epub 2018 Nov 27.

Department of Anthropology, University of California, Davis, California.

Social instability in primate groups has been used as a model to understand how social stress affects human populations. While it is well established that individual cercopithecines have different temperaments or personalities, little is known about how temperament mediates the experience of social instability in large, naturalistic groups. Here, we report findings from a study tracking a newly formed group of captive rhesus macaques (Macaca mulatta). Read More

Am J Primatol 2018 Nov 26:e22934. Epub 2018 Nov 26.

Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown, Ohio.

The lab and field provide differing approaches to studying primate biology. We outline the challenges and benefits of these approaches and demonstrate how collaboration can help bridge these perspectives to provide complementary insight into primate adaptive pathways. With this aim, our collaboration has made tangible insights into the ecological physiology of several primate species, and also yielded more subtle, intangible professional benefits. Read More

Am J Primatol 2018 Nov;80(11):e22929

Research Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry/Key Laboratory of Forest Ecology and Environment of State Forestry Administration, Haidian, Beijing, China.

Climate change threatens endangered species and challenges current conservation strategies. Effective conservation requires vulnerability assessments for species susceptible to climate change and adaptive strategies to mitigate threats associated with climate. In this paper, we used the Maxent to model the impacts of climate change on habitat suitability of Sichuan golden monkey Rhinopithecus roxellana. Read More

Am J Primatol 2018 Oct 30:e22928. Epub 2018 Oct 30.

Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, Wisconsin.

The northern muriqui (Brachyteles hypoxanthus) is a critically endangered species endemic to the Atlantic Forest of southeastern Brazil. Long-term observational studies of wild muriquis have provided many insights into the behavioral ecology and life history of this species. However, nearly everything that is currently known about the northern muriqui's behavioral endocrinology has come from combining our respective expertise in noninvasive field and laboratory research. Read More

Am J Primatol 2018 Dec 30;80(12):e22930. Epub 2018 Oct 30.

Zoo New England, Franklin Park, Boston, Massachusetts.

Am J Primatol 2018 Nov 23;80(11):e22925. Epub 2018 Oct 23.

Primate Behavioral Ecology Lab, Instituto de Neuroetología, Universidad Veracruzana, Xalapa, México.

The reproductive process of female primates is energetically constrained. However, while there is extensive evidence about factors that influence the maintenance of gestation and lactation, less is known about energetic correlates of cycling and the occurrence of conception in wild primates. We examined how female physical condition affected the occurrence of conception and interbirth intervals (IBI) in female mantled howler monkeys, a species in which females experience long non-conceptive periods. Read More

Am J Primatol 2018 Nov 23;80(11):e22910. Epub 2018 Oct 23.

Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.

Male-female social interactions may vary according to female receptivity, female parity, and male dominance rank. Such variation may be less apparent in species with one-male mating systems than those with multimale mating systems, as within-group male-male competition and female mate choice are absent. Examining variation in male-female interactions in multimale groups in species with a predominantly one-male mating system may help to shed light on plasticity in behavioral patterns and the evolution of mating systems. Read More