Showing papers on "Primate published in 2014"
TL;DR: It is shown that CR significantly improves age-related and all-cause survival in monkeys on a long-term ~30% restricted diet since young adulthood, and indicates that the benefits of CR on ageing are conserved in primates.
Abstract: Caloric restriction (CR) without malnutrition increases longevity and delays the onset of age-associated disorders in short-lived species, from unicellular organisms to laboratory mice and rats. The value of CR as a tool to understand human ageing relies on translatability of CR's effects in primates. Here we show that CR significantly improves age-related and all-cause survival in monkeys on a long-term ~30% restricted diet since young adulthood. These data contrast with observations in the 2012 NIA intramural study report, where a difference in survival was not detected between control-fed and CR monkeys. A comparison of body weight of control animals from both studies with each other, and against data collected in a multi-centred relational database of primate ageing, suggests that the NIA control monkeys were effectively undergoing CR. Our data indicate that the benefits of CR on ageing are conserved in primates.
603 citations
TL;DR: Comparative analyses of the primate vaginal microbiome using pyrosequencing of the 16S rRNA genes of a phylogenetically broad range of primates indicated that all primates exhibited host-specific vaginal microbiota and that humans were distinct from other primates in both microbiome composition and diversity.
Abstract: Bacterial communities colonizing the reproductive tracts of primates (including humans) impact the health, survival and fitness of the host, and thereby the evolution of the host species. Despite their importance, we currently have a poor understanding of primate microbiomes. The composition and structure of microbial communities vary considerably depending on the host and environmental factors. We conducted comparative analyses of the primate vaginal microbiome using pyrosequencing of the 16S rRNA genes of a phylogenetically broad range of primates to test for factors affecting the diversity of primate vaginal ecosystems. The nine primate species included: humans (Homo sapiens), yellow baboons (Papio cynocephalus), olive baboons (Papio anubis), lemurs (Propithecus diadema), howler monkeys (Alouatta pigra), red colobus (Piliocolobus rufomitratus), vervets (Chlorocebus aethiops), mangabeys (Cercocebus atys) and chimpanzees (Pan troglodytes). Our results indicated that all primates exhibited host-specific vaginal microbiota and that humans were distinct from other primates in both microbiome composition and diversity. In contrast to the gut microbiome, the vaginal microbiome showed limited congruence with host phylogeny, and neither captivity nor diet elicited substantial effects on the vaginal microbiomes of primates. Permutational multivariate analysis of variance and Wilcoxon tests revealed correlations among vaginal microbiota and host species-specific socioecological factors, particularly related to sexuality, including: female promiscuity, baculum length, gestation time, mating group size and neonatal birth weight. The proportion of unclassified taxa observed in nonhuman primate samples increased with phylogenetic distance from humans, indicative of the existence of previously unrecognized microbial taxa. These findings contribute to our understanding of host–microbe variation and coevolution, microbial biogeography, and disease risk, and have important implications for the use of animal models in studies of human sexual and reproductive diseases.
136 citations
TL;DR: Seven juvenile monkeys trained to recognize three distinct sets of shapes developed regions that were selectively responsive to each trained set, indicating that the location of training effects does not depend on function or expertise, but rather on some kind of proto-organization.
Abstract: Primate inferotemporal cortex is subdivided into domains for biologically important categories, like faces, bodies, and scenes, as well as domains for culturally entrained categories, like text or buildings. These domains are in stereotyped locations in most humans and monkeys. To ask what determines the location of such domains, we intensively trained 7 juvenile monkeys to recognize 3 distinct sets of shapes. After training, the monkeys developed regions that were selectively responsive to each trained set. The location of each specialization was similar across monkeys, despite differences in training order. This indicates that the location of training effects does not depend on function or expertise, but rather some kind of proto-organization. We explore the possibility that this proto-organization is retinotopic or shape-based.
134 citations
TL;DR: It is argued that the marmoset monkey provides a good subject for studies of a complex visual system, which will likely allow an important bridge linking experiments in animal models to humans.
Abstract: Humans are diurnal primates with high visual acuity at the center of gaze. Although primates share many similarities in the organization of their visual centers with other mammals, and even other species of vertebrates, their visual pathways also show unique features, particularly with respect to the organization of the cerebral cortex. Therefore, in order to understand some aspects of human visual function, we need to study non-human primate brains. Which species is the most appropriate model? Macaque monkeys, the most widely used non-human primates, are not an optimal choice in many practical respects. For example, much of the macaque cerebral cortex is buried within sulci, and is therefore inaccessible to many imaging techniques, and the postnatal development and lifespan of macaques are prohibitively long for many studies of brain maturation, plasticity, and aging. In these and several other respects the marmoset, a small New World monkey, represents a more appropriate choice. Here we review the visual pathways of the marmoset, highlighting recent work that brings these advantages into focus, and identify where additional work needs to be done to link marmoset brain organization to that of macaques and humans. We will argue that the marmoset monkey provides a good subject for studies of a complex visual system, which will likely allow an important bridge linking experiments in animal models to humans.
134 citations
TL;DR: The results indicate that rhesus macaques map number onto space, suggesting that the association between number and space in human cognition is not purely a result of cultural experience and instead has deep evolutionary roots.
92 citations
TL;DR: It is shown that the New World monkeys, comprising the third of all primate species, have human-like sialic acid biology, and this striking molecular convergence provides a mechanism that could explain the long-standing observation thatNew World monkeys are susceptible to some human diseases that cannot be transmitted to other primates.
Abstract: Human sialic acid biology is unusual and thought to be unique among mammals. Humans lack a functional cytidine monophosphate-N-acetylneuraminic acid hydroxylase (CMAH) protein and cannot synthesize the sugar Neu5Gc, an innate mammalian signal of self. Losing this sugar changed how humans interact with some of our deadliest pathogens: malaria, influenza, and streptococcus among others. We show that the New World monkeys, comprising the third of all primate species, have human-like sialic acid biology. They have lost Neu5Gc because of an independent CMAH inactivation ~30 million years ago (mya) (compared to ~3 mya in hominids). This parallel loss of Neu5Gc opens sialic acid biology to comparative phylogenetic analysis and reveals an unexpected conservation priority. New World monkeys risk infection by human pathogens that can recognize cells in the absence of Neu5Gc. This striking molecular convergence provides a mechanism that could explain the long-standing observation that New World monkeys are susceptible to some human diseases that cannot be transmitted to other primates.
75 citations
TL;DR: Findings are consistent with prior evidence in humans that intranasal administration of OT specifically enhances visual attention to the eye region compared to other informative facial features, thus validating the use of non-human primates to mechanistically explore how OT modulates social information processing and behavior.
Abstract: Human and non-human primates rely on the ability to perceive and interpret facial expressions to guide effective social interactions. The neuropeptide oxytocin (OT) has been shown to have a critical role in the perception of social cues, and in humans to increase the number of saccades to the eye region. To develop a useful primate model for the effects of OT on information processing, we investigated the influence of OT on gaze behavior during face processing in rhesus macaques. Forty-five minutes after a single intranasal dose of either 24IU OT or saline, monkeys completed a free-viewing task during which they viewed pictures of conspecifics displaying one of three facial expressions (neutral, open-mouth threat or bared-teeth) for 5 seconds. The monkey was free to explore the face on the screen while the pattern of eye movements was recorded. OT did not increase overall fixations to the face compared to saline. Rather, when monkeys freely viewed conspecific faces, OT increased fixations to the eye region relative to the mouth region. This effect of OT was particularly pronounced when face position on the screen was manipulated so that the eye region was not the first facial feature seen by the monkeys. Together these findings are consistent with prior evidence in humans that intranasal administration of OT specifically enhances visual attention to the eye region compared to other informative facial features, thus validating the use of non-human primates to mechanistically explore how OT modulates social information processing and behavior.
69 citations
TL;DR: This evolutionary renovation of L/M opsin polymorphism in atelines illustrates a previously unappreciated dynamism of opsin genes in shaping primate colour vision.
Abstract: New World monkeys exhibit prominent colour vision variation due to allelic polymorphism of the long-to-middle wavelength (L/M) opsin gene. The known spectral variation of L/M opsins in primates is broadly determined by amino acid composition at three sites: 180, 277 and 285 (the ‘three-sites’ rule). However, two L/M opsin alleles found in the black-handed spider monkeys (Ateles geoffroyi) are known exceptions, presumably due to novel mutations. The spectral separation of the two L/M photopigments is 1.5 times greater than expected based on the ‘three-sites’ rule. Yet the consequence of this for the visual ecology of the species is unknown, as is the evolutionary mechanism by which spectral shift was achieved. In this study, we first examine L/M opsins of two other Atelinae species, the long-haired spider monkeys (A. belzebuth) and the common woolly monkeys (Lagothrix lagotricha). By a series of site-directed mutagenesis, we show that a mutation Y213D (tyrosine to aspartic acid at site 213) in the ancestral opsin of the two alleles enabled N294K, which occurred in one allele of the ateline ancestor and increased the spectral separation between the two alleles. Second, by modelling the chromaticity of dietary fruits and background leaves in a natural habitat of spider monkeys, we demonstrate that chromatic discrimination of fruit from leaves is significantly enhanced by these mutations. This evolutionary renovation of L/M opsin polymorphism in atelines illustrates a previously unappreciated dynamism of opsin genes in shaping primate colour vision.
67 citations
TL;DR: Findings support the hypothesis that there is a reduced OSA in at least some haplorhines, and this can be linked to diminished posterosuperior dimensions of the nasal fossae, and imply that airflow patterns in the olfactory region differ among primates.
Abstract: The two major groups of primates differ in internal nasal anatomy. Strepsirrhines (e.g., lemurs) have more numerous turbinals and recesses compared with haplorhines (e.g., monkeys). Since detailed quantitative comparisons of nasal surface area (SA) have not been made, we measured mucosa in serially sectioned monkeys (Callithrix jacchus, Cebuella pygmaea). Data were compared with previously published findings on the mouse lemur, Microcebus murinus. The nasal airways were digitally reconstructed using computed tomography scanned heads of Cebuella and Microcebus. In addition, morphometric and functional analyses were carried out using segmented photographs of the histological sections of Cebuella and Microcebus. The SA of the ethmoturbinal complex is about half as large in marmosets compared with Microcebus, and is covered with less olfactory mucosa (18%–24% in marmosets, compared with ∼50% in Microcebus). Whereas the ethmoturbinal complex of Microcebus bears half of the total olfactory mucosa in the nasal airway, most (∼80%) olfactory mucosa is distributed on other surfaces in the marmosets (e.g., nasal septum). A comparison to previously published data suggests all primate species have less olfactory surface area (OSA) compared with other similar-sized mammals, but this is especially true of marmosets. Taken together, these findings support the hypothesis that there is a reduced OSA in at least some haplorhines, and this can be linked to diminished posterosuperior dimensions of the nasal fossae. However, haplorhines may have minimized their olfactory loss by redistributing olfactory mucosa on non-turbinal surfaces. Our findings also imply that airflow patterns in the olfactory region differ among primates. Anat Rec, 297:2093–2104, 2014. © 2014 Wiley Periodicals, Inc.
63 citations
TL;DR: Primate susceptibility was evaluated and it was found that 100% of intracerebrally inoculated and 92% of orally inoculated squirrel monkeys were susceptible, but cynomolgus macaques were not, suggesting possible low risk for humans.
Abstract: Chronic wasting disease is a prion disease of cervids. Assessment of its zoonotic potential is critical. To evaluate primate susceptibility, we tested monkeys from 2 genera. We found that 100% of intracerebrally inoculated and 92% of orally inoculated squirrel monkeys were susceptible, but cynomolgus macaques were not, suggesting possible low risk for humans.
63 citations
TL;DR: It is found that significant overlap in the diet of the Ka'apor capuchin and Sapajus is found, highlighting the urgency to increase knowledge of the ecological needs of C. kaapori and understand synergistic effects of sympatry with competitive species, increasing forest fragmentation, and widespread human impact on C.kaapori sustainability.
Abstract: The Ka'apor capuchin, Cebus kaapori, is perhaps the most endangered primate of the Brazilian Amazon. Endemic to a region with extreme intensification of habitat-degrading activities, it survives in remnant populations in a completely fragmented landscape. Before now, the only data available were isolated observations of feeding, locality records, and information on population densities and group size obtained during census. Here we present the first data on the activity budget, diet, and daily path length of the species, and compare our preliminary results with those for other capuchin monkeys. A group of nine Ka'apor capuchins was monitored over a period of four months during the dry season in the Goianesia do Para municipality, Para, Brazil. We used instantaneous scan sampling (n = 4,647 scans) to construct an activity budget for the monkeys, and we identified the plants in their diet to species level (n = 41 plant taxa), allowing us to compare dietary overlap with other gracile capuchin species, as well as with the robust capuchin (Sapajus spp.), a potential competitor present throughout the range of the Ka'apor capuchin. Like other species of gracile capuchins, C. kaapori was highly frugivorous, with the vast majority of the feeding records of arils and fruit pulp (74%), supplemented by arthropods (13%) and seeds (10%), although diet composition was highly variable across months. The group used a total area of 62.4 ha during the study period, and average daily path length was 2,173 m (±400 m), with the entire home range utilized in every month of the study. We found significant overlap in the diet of the Ka'apor capuchin and Sapajus, highlighting the urgency to increase knowledge of the ecological needs of C. kaapori and understand synergistic effects of sympatry with competitive species, increasing forest fragmentation, and widespread human impact on C. kaapori sustainability. Am. J. Primatol. 76:919–931, 2014. © 2014 Wiley Periodicals, Inc.
TL;DR: This study is the first to describe the detailed daily feeding rhythm in proboscis monkeys (Nasalis larvatus) based on data collected from both riverbank and inland habitats, and finds that the differences in the feeding rhythm among the seasons appeared to reflect the time spent eating fruit and/or the availability of fruit.
Abstract: In non-human primates, the daily feeding rhythm, i.e., temporal fluctuation in feeding activity across the day, has been described but has rarely received much analytical interpretation, though it may play a crucial part in understanding the adaptive significance of primate foraging strategies. This study is the first to describe the detailed daily feeding rhythm in proboscis monkeys (Nasalis larvatus) based on data collected from both riverbank and inland habitats. From May 2005 to May 2006, data on feeding behavior in a group of proboscis monkeys consisting of an alpha-male, six adult females and immatures was collected via continuous focal animal sampling technique in a forest along the Menanggul River, Sabah, Malaysia. In both the male and females, the highest peak of feeding activity was in the late afternoon at 15:00–17:00, i.e., shortly before sleeping. The differences in the feeding rhythm among the seasons appeared to reflect the time spent eating fruit and/or the availability of fruit; clearer feeding peaks were detected when the monkeys spent a relevant amount of time eating fruit, but no clear peak was detected when fruit eating was less frequent. The daily feeding rhythm was not strongly influenced by daily temperature fluctuations. When comparing the daily feeding rhythm of proboscis monkeys to that of other primates, one of the most common temporal patterns detected across primates was a feeding peak in the late afternoon, although it was impossible to demonstrate this statistically because of methodological differences among studies.
TL;DR: Hässler’s (1967) laminar scheme for V1 provides a more consistent representation of neocortical layers across all primates, including humans, and facilitates comparisons of V1 lamination with non-primate species.
Abstract: Primary visual cortex (V1) is clearly distinguishable from other cortical areas by its distinctive pattern of neocortical lamination across mammalian species. In some mammals, primates in particular, the layers of V1 are further divided into a number of sublayers based on their anatomical and functional characteristics. While these sublayers are easily recognizable across a range of primates, the exact number of divisions in each layer and their relative position within the depth of V1 has been inconsistently reported, largely due to conflicting schemes of nomenclature for the V1 layers. This conflict centers on the definition of layer 4 in primate V1, and the subdivisions of layer 4 that can be consistently identified across primate species. Brodmann’s (1909) laminar scheme for V1 delineates three subdivisions of layer 4 in primates, based on cellular morphology and geniculate inputs in anthropoid monkeys. In contrast, Hassler’s (1967) laminar scheme delineates a single layer 4 and multiple subdivisions of layer 3, based on comparisons of V1 lamination across the primate lineage. In order to clarify laminar divisions in primate visual cortex, we performed NeuN and VGLUT2 immunohistochemistry in V1 of chimpanzees, Old World macaque monkeys, New World squirrel, owl, and marmoset monkeys, prosimian galagos and mouse lemurs, and nonprimate, but highly visual, tree shrews. By comparing the laminar divisions identified by each method across species, we find that Hassler’s (1967) laminar scheme for V1 provides a more consistent representation of neocortical layers across all primates, including humans, and facilitates comparisons of V1 lamination with nonprimate species. These findings, along with many others, support the consistent use of Hassler’s laminar scheme in V1 research.
TL;DR: The results suggest that the disorganized subfield maps and robust binocular suppression of amblyopic V2 neurons are likely to adversely affect the higher stages of cortical processing resulting in position uncertainty and image distortion.
Abstract: Experiencing different quality images in the two eyes soon after birth can cause amblyopia, a developmental vision disorder Amblyopic humans show the reduced capacity for judging the relative position of a visual target in reference to nearby stimulus elements (position uncertainty) and often experience visual image distortion Although abnormal pooling of local stimulus information by neurons beyond striate cortex (V1) is often suggested as a neural basis of these deficits, extrastriate neurons in the amblyopic brain have rarely been studied using microelectrode recording methods The receptive field (RF) of neurons in visual area V2 in normal monkeys is made up of multiple subfields that are thought to reflect V1 inputs and are capable of encoding the spatial relationship between local stimulus features We created primate models of anisometropic amblyopia and analyzed the RF subfield maps for multiple nearby V2 neurons of anesthetized monkeys by using dynamic two-dimensional noise stimuli and reverse correlation methods Unlike in normal monkeys, the subfield maps of V2 neurons in amblyopic monkeys were severely disorganized: subfield maps showed higher heterogeneity within each neuron as well as across nearby neurons Amblyopic V2 neurons exhibited robust binocular suppression and the strength of the suppression was positively correlated with the degree of hereogeneity and the severity of amblyopia in individual monkeys Our results suggest that the disorganized subfield maps and robust binocular suppression of amblyopic V2 neurons are likely to adversely affect the higher stages of cortical processing resulting in position uncertainty and image distortion
01 Sep 2014
TL;DR: Four traditional and four more recent histological markers applied to brain sections of V1 and adjoining secondary visual cortex in macaque monkeys, chimpanzees, and humans in order to compare identifiable layers and sublayers in both cortical areas across these species support the conclusion that the most popular scheme of V 1 lamination misidentifies subl layers of layer 3 as sublayer of layer 4.
Abstract: The layers and sublayers of primary visual cortex, or V1, in primates are easily distinguishable compared to those in other cortical areas, and are especially distinct in anthropoid primates - monkeys, apes, and humans - where they also vary in histological appearance. This variation in primate-specific specialization has led to a longstanding confusion over the identity of layer 4 and its proposed sublayers in V1. As the application of different histological markers relate to the issue of defining and identifying layers and sublayers, we applied four traditional and four more recent histological markers to brain sections of V1 and adjoining secondary visual cortex (V2) in macaque monkeys, chimpanzees, and humans in order to compare identifiable layers and sublayers in both cortical areas across these species. The use of Nissl, neuronal nuclear antigen (NeuN), Gallyas myelin, cytochrome oxidase (CO), acetylcholinesterase (AChE), nonphosphorylated neurofilament H (SMI-32), parvalbumin (PV), and vesicular glutamate transporter 2 (VGLUT2) preparations support the conclusion that the most popular scheme of V1 lamination, that of Brodmann, misidentifies sublayers of layer 3 (3Bβ and 3C) as sublayers of layer 4 (4A and 4B), and that the specialized sublayer of layer 3 in monkeys, 3Bβ, is not present in humans. These differences in interpretation are important as they relate to the proposed functions of layer 4 in primate species, where layer 4 of V1 is a layer that receives and processes information from the visual thalamus, and layer 3 is a layer that transforms and distributes information to other cortical areas.
TL;DR: Investigating the intrinsic connectivity networks in four primate species using resting-state fMRI to evaluate the intra- and inter- hemispheric coherences of spontaneous BOLD fluctuation indicates that this pattern of within-hemisphere connectivity distinguishes humans from nonhuman primates.
Abstract: The human behavioral repertoire greatly exceeds that of nonhuman primates. Anatomical specializations of the human brain include an enlarged neocortex and prefrontal cortex (Semendeferi et al. in Am J Phys Anthropol 114:224–241, 2001), but regional enlargements alone cannot account for these vast functional differences. Hemispheric specialization has long believed to be a major contributing factor to such distinctive human characteristics as motor dominance, attentional control and language. Yet structural cerebral asymmetries, documented in both humans and some nonhuman primate species, are relatively minor compared to behavioral lateralization. Identifying the mechanisms that underlie these functional differences remains a goal of considerable interest. Here, we investigate the intrinsic connectivity networks in four primate species (humans, chimpanzees, baboons, and capuchin monkeys) using resting-state fMRI to evaluate the intra- and inter- hemispheric coherences of spontaneous BOLD fluctuation. All three nonhuman primate species displayed lateralized functional networks that were strikingly similar to those observed in humans. However, only humans had multi-region lateralized networks, which provide fronto-parietal connectivity. Our results indicate that this pattern of within-hemisphere connectivity distinguishes humans from nonhuman primates.
TL;DR: Proboscis monkeys might be a model for convergent evolution towards rumination in a non-ungulate taxon because of their exceptional chewing efficiency, as ruminants have among mammals.
Abstract: In mammalian herbivores, faecal particle size indicates chewing efficiency. Proboscis monkeys (Nasalis larvatus) are foregut fermenters in which regurgitation and remastication (i.e. rumination) was observed in the wild, but not with the same consistency as found in ruminants and camelids. To test whether this species has exceptional chewing efficiency among primates, as ruminants have among mammals, we compared faecal particle size in free-ranging specimens with those of 12 other primate species. The discrete mean faecal particle size (dMEAN) increased with body mass (M) as dMEAN (mm) = 0.65 (95 % confidence interval 0.49–0.87) M0.33 (0.23–0.43) in simple-stomached species. At 0.53 ± 0.09 mm, dMEAN of proboscis monkeys was particularly small for their average M (15 kg) and significantly smaller than values of two other foregut fermenting primate species. While we cannot exclude other reasons for the exceptional chewing efficiency in proboscis monkeys, this represents circumstantial evidence for regular use of rumination in this species. Thus, proboscis monkeys might be a model for convergent evolution towards rumination in a non-ungulate taxon.
TL;DR: Orangutans outperformed capuchin monkeys, suggesting that ape species may generally show better delay of gratification and delay maintenance abilities than monkeys, however, more studies are necessary to rule out alternative hypotheses on the distribution ofdelay maintenance abilities across primate species.
Abstract: There is considerable evidence indicating that chimpanzees can delay gratification for extended time intervals, particularly in the accumulation task in which food items accumulate within a participant's reach until the participant begins to consume them. However, there is limited evidence that other ape species might also exhibit this capacity, despite there being a number of similar studies indicating that nonape species (e.g., monkeys and birds) can delay gratification, but not for nearly as long as chimpanzees. To help define the taxonomic distribution of delay of gratification behavior in the order Primates, we tested 6 orangutans in the current experiments and compared their performance with comparable data from a previous study with capuchin monkeys. We varied delay length and visibility of the items that were still available for accumulation to determine the impact of these factors on performance. Species differences on the accumulation task emerged when comparing the current data to data from a previous study. Orangutans outperformed capuchin monkeys, suggesting that ape species may generally show better delay of gratification and delay maintenance abilities than monkeys. However, more studies are necessary to rule out alternative hypotheses on the distribution of delay maintenance abilities across primate species.
01 Jan 2014
TL;DR: This book discusses how ecological conditions affect the abundance and social organization of folivorous monkeys and social conflict management in primates and cetacean societies, and social touch in apes and dolphins.
Abstract: Part 1: Social Ecology.- 1 How ecological conditions affect the abundance and social organization of folivorous monkeys.- 2 Dusky dolphins: Flexibility in foraging and social strategies.- 3 Socioecological flexibility of gorillas and chimpanzees.- 4 You are what you eat: Foraging specializations and their influence on the social organization and behaviour of killer whales.- 5 Japanese macaques: Habitat-driven divergence in social dynamics.- 6 Shark Bay bottlenose dolphins: A case study for defining and measuring sociality.- Part 2: Life History and Social Evolution.- 7 Female coexistence and competition in ringtailed lemurs: A review of a long-term study at Berenty, Madagascar.- 8 Social structure and life history of bottlenose dolphins near Sarasota Bay, Florida: Insights from four decades and five generations.- 9 Life history tactics in monkeys and apes: Focus on female dispersal species.- 10 Social conflict management in primates: Is there a case for dolphins?.- 11 Evolution of small-group territoriality in gibbons.- Part 3: Demography, Genetics, and Issues in Conservation.- 12 Northern muriqui monkeys: Behavior, demography, and conservation.- 13 Indo-Pacific humpback dolphins: A demographic perspective of a threatened species.- 14 Mountain gorillas: A shifting demographic landscape.- 15 Population genetics in the conservation of cetaceans and primates.- 16 Eco-toxicants: A growing global threat.- Part 4: Selected Topics in Comparative Behavior.- 17 Observing and quantifying cetacean behavior in the wild: Current problems, limitations and future directions.- 18 Social network analysis: Applications to primate and cetacean societies.- 19 Social touch in apes and dolphins.- 20 Non-conceptive sexual interactions in monkeys, apes, and toothed whales.- 21 A mix of species: Associations of heterospecifics among primates and dolphins.- BM Index.
01 Jan 2014
TL;DR: High altitude prosimian primates have been studied extensively in the literature as discussed by the authors, with a focus on the effects of altitude on the conservation of lemurs in South East Madagascar.
Abstract: High Altitude Prosimian Primates.- 1. Effects of Altitude on the Conservation Biogeography of Lemurs in South East Madagascar.- 2. Hibernation patterns of dwarf lemurs in the high altitude forests of eastern Madagascar.- 3. Altitudinal Distribution and Ranging Patterns of Pygmy Tarsiers (Tarsius pumilus).- High Altitude Monkeys.- 4. Biogeography and conservation of Andean primates in Peru.- 5. Population density and ecological traits of high land woolly monkeys at Cueva de los Guacharos National Park, Colombia.- 6. Seed Dispersal by Woolly Monkeys in Cueva de los Guacharos National Park (Colombia): An amazonian primate dispersing montane plants.- 7. Distribution and ecology of the most tropical of the high-elevation montane colobines: the ebony langur on Java.- 8. Snow tolerance of Japanese macaques inhabiting high-latitude mountainous forests of Japan.- 9. Seasonal and altitudinal migration of Japanese macaques in the Northern Japan Alps.- 10. Rhinopithecus bieti at Xiaochangdu, Tibet: Adaptations to a marginal environment.- 11. Nutritional implications of the high-elevation lifestyle of Rhinopithecus bieti.- 12. Variation in primate abundance along an elevational gradient in the Udzungwa.- 13. Deriving Conservation Status for a High Altitude Population: Golden Monkeys of Mgahinga Gorilla National Park, Uganda.- High Altitude Apes.- 14. High Altitude Diets: Implications for the Feeding and Nutritional Ecology of Mountain Gorillas.- 15. Preliminary data on the highland Sumatran orangutans (Pongo abelii) of Batang Toru.- 16. Modern Human Biological Adaptations to High-Altitude Environments in the Andean Archaeological Record.-17. High Altitude Primates, Extreme Primates, and Anthropological Primatology (There is More to Human Evolution than Tool Use, Culture, or African Apes).
TL;DR: Comparison of 2010 data with similar data on earlier primate/mammalian mortality events reported for BCI and for Corcovado, Costa Rica indicates that the understanding of the effects of natural disturbances on wild primate populations is not profound.
Abstract: Though the harmful effects anthropogenic disturbances pose to wild primates are well appreciated, comparatively little is known about the effects of natural disturbances. From December 2010 to January 2011, different mortality patterns were observed for two primate species, capuchins and howler monkeys, on Barro Colorado Island (BCI), Panama. Unusually high rainfall in 2010 was associated with census and cadaver data indicating the rapid loss of >70% of the capuchin population in late 2010 to early 2011. In contrast, over this same period, no decline was documented for howler monkeys and cadaver data for howlers was unexceptional. The high mortality experienced by the capuchin population was unexpected and its extent was not fully appreciated until the event was largely over. Explanations proposed for it included effects of hypothermia, disease or a shortage of some essential nutrient(s). Of these, the dietary explanation seems most probable. BCI capuchins depend most heavily on arthropod foods in December, when few higher quality ripe fruits are available. The unprecedented high rainfall in December 2010 is hypothesized to have largely eliminated the arthropod peak expected on BCI each December. A lack of protein-rich arthropods, when coupled with the climatic and nutritional stress capuchins generally experience at this time of year, appears to have precipitated the rapid die-off of most of the island's capuchin population. As howler monkeys obtain dietary protein primarily from leaves, a shortage of edible arthropods would not affect howler numbers. Comparison of our 2010 data with similar data on earlier primate/mammalian mortality events reported for BCI and for Corcovado, Costa Rica indicates that our understanding of the effects of natural disturbances on wild primate populations is not profound. We suggest that more research be devoted to this increasingly timely topic, so important to conservation policy. Am. J. Primatol. © 2013 Wiley Periodicals, Inc.
TL;DR: Comparison of these data with the data from bird studies points toward the existence of different orientation-tuned mechanisms between primate and nonprimate species.
Abstract: A long-standing debate surrounds the issue of whether human and nonhuman animals share the same perceptual mechanisms. In humans, the Zollner illusion occurs when two parallel lines appear to be convergent when oblique crosshatching lines are superimposed. Although one baboon study suggests that they too might perceive this illusion, the results of that study were unclear, whereas two recent studies suggest that birds see this illusion in the opposite direction from humans. It is currently unclear whether these mixed results are an artifact of the experimental design or reflect a peculiarity of birds’ visual system or, instead, a wider phenomenon shared among nonhuman mammals. Here, we trained 6 monkeys to select the narrower of two gaps at the end of two convergent lines. Three different conditions were set up: control (no crosshatches), perpendicular (crosshatches not inducing the illusion), and Zollner (crosshatches inducing the illusion in humans). During training, the degrees of convergence between the two lines ranged from 15° to 12°. Monkeys that reached the training criterion were tested with more difficult discriminations (11°–1°), including probe trials with parallel lines (0°). The results showed that monkeys perceived the Zollner illusion in the same direction as humans. Comparison of these data with the data from bird studies points toward the existence of different orientation-tuned mechanisms between primate and nonprimate species.
TL;DR: The primate gambling task presented here is a useful methodology for disentangling strategies of variance avoidance and reward maximization and suggests that individual differences in strategies for interacting with variance and Reward maximization are present in apes, but not in capuchin monkeys.
Abstract: Humans will, at times, act against their own economic self-interest, for example, in gambling situations. To explore the evolutionary roots of this behavior, we modified a traditional human gambling task, the Iowa Gambling Task (IGT), for use with chimpanzees, capuchin monkeys and humans. We expanded the traditional task to include two additional payoff structures to fully elucidate the ways in which these primate species respond to differing reward distributions versus overall quantities of rewards, a component often missing in the existing literature. We found that while all three species respond as typical humans do in the standard IGT payoff structure, species and individual differences emerge in our new payoff structures. Specifically, when variance avoidance and reward maximization conflicted, roughly equivalent numbers of apes maximized their rewards and avoided variance, indicating that the traditional payoff structure of the IGT is insufficient to disentangle these competing strategies. Capuchin monkeys showed little consistency in their choices. To determine whether this was a true species difference or an effect of task presentation, we replicated the experiment but increased the intertrial interval. In this case, several capuchin monkeys followed a reward maximization strategy, while chimpanzees retained the same strategy they had used previously. This suggests that individual differences in strategies for interacting with variance and reward maximization are present in apes, but not in capuchin monkeys. The primate gambling task presented here is a useful methodology for disentangling strategies of variance avoidance and reward maximization.
TL;DR: Data on the expression of proteins indispensable for peripheral heterochromatin maintenance in rod cells support the view that the primate ancestors were nocturnal and transition to diurnality occurred independently in several primate and related groups: Tupaia, diurnal lemurs, and, at least partially independently, in Simiiformes (monkeys and apes) and Tarsiiforme.
Abstract: Diurnality, associated with enhanced visual acuity and color vision, is typical of most modern Primates. However, it remains a matter of debate when and how many times primates re-acquired diurnality or returned to nocturnality. We analyzed the features specific to nocturnal and diurnal vision that were recently found in the nuclei of mammalian rod photoreceptor cells in 11 species representing various groups of the Primates and related tree shrew and colugo. In particular, heterochromatin in rod nuclei of nocturnal mammals is clustered in the center of rod nuclei (inverted architecture), whereas rods of diurnal mammals retain rods with peripheral heterochromatin (conventional architecture). Rod nuclei of the nocturnal owl monkey have a state transitional to the inverted one. Surprisingly, rod nuclei of the tarsier have a conventional nuclear architecture typical for diurnal mammals, strongly implying that recent Tarsiiformes returned to nocturnality from the diurnal state. Diurnal lemurs retain inverted rod nuclei typical of nocturnal mammals, which conforms to the notion that the ancestors of all Lemuroidea were nocturnal. Data on the expression of proteins indispensable for peripheral heterochromatin maintenance (and, respectively, conventional or inverted nuclear organization) in rod cells support the view that the primate ancestors were nocturnal and transition to diurnality occurred independently in several primate and related groups: Tupaia, diurnal lemurs, and, at least partially independently, in Simiiformes (monkeys and apes) and Tarsiiformes.
TL;DR: It is proposed that alternate spinal afferents, in addition to the few spared primary axon afferentS in the dorsal columns, likely have a major role in the reactivation pattern and return of function in lesion and control monkeys.
Abstract: Lesions of the dorsal columns at a mid-cervical level render the hand representation of the contralateral primary somatosensory cortex (area 3b) unresponsive. Over weeks of recovery, most of this cortex becomes responsive to touch on the hand. Determining functional properties of neurons within the hand representation is critical to understanding the neural basis of this adaptive plasticity. Here, we recorded neural activity across the hand representation of area 3b with a 100-electrode array and compared results from owl monkeys and squirrel monkeys 5–10 weeks after lesions with controls. Even after extensive lesions, performance on reach-to-grasp tasks returned to prelesion levels, and hand touches activated territories mainly within expected cortical locations. However, some digit representations were abnormal, such that receptive fields of presumably reactivated neurons were larger and more often involved discontinuous parts of the hand compared with controls. Hand stimulation evoked similar neuronal firing rates in lesion and control monkeys. By assessing the same monkeys with multiple measures, we determined that properties of neurons in area 3b were highly correlated with both the lesion severity and the impairment of hand use. We propose that the reactivation of neurons with near-normal response properties and the recovery of near-normal somatotopy likely supported the recovery of hand use. Given the near-completeness of the more extensive dorsal column lesions we studied, we suggest that alternate spinal afferents, in addition to the few spared primary axon afferents in the dorsal columns, likely have a major role in the reactivation pattern and return of function.
TL;DR: The results indicate that monkeys’ viewing preferences, as assessed by a visual preference task, are modulated by several factors, species and dominance being the most influential.
Abstract: Humans, great apes and old world monkeys show selective attention to faces depending on conspeci- ficity, familiarity, and social status supporting the view that primates share similar face processing mechanisms. Although many studies have been done on face scanning strategy in monkeys and humans, the mechanisms influ- encing viewing preference have received little attention. To determine how face categories influence viewing prefer- ence in humans and rhesus macaques (Macaca mulatta), we performed two eye-tracking experiments using a visual preference task whereby pairs of faces from different species were presented simultaneously. The results indi- cated that viewing time was significantly influenced by the pairing of the face categories. Humans showed a strong bias towards an own-race face in an Asian-Caucasian condition. Rhesus macaques directed more attention towards non-human primate faces when they were paired with human faces, regardless of the species. When rhesus faces were paired with faces from Barbary macaques (Macaca sylvanus) or chimpanzees (Pan troglodytes), the novel species' faces attracted more attention. These results indicate that monkeys' viewing preferences, as assessed by a visual preference task, are modulated by several factors, species and dominance being the most influential.
01 Jan 2014
TL;DR: In this article, the authors focus on the middle temporal area (MT), the most extensively studied extrastriate area in primates, and discuss similarities and differences between marmosets and macaques.
Abstract: Although macaque monkeys have been dominant models in visual neuroscience, recent scientific advances suggest that marmosets provide a valuable alternative in the context of many types of experiments. Here we focus on the middle temporal area (MT), the most extensively studied extrastriate area in primates, and discuss similarities and differences between marmosets and macaques. The basic response properties of MT cells are similar in these species, including direction selectivity, speed tuning, and receptive field centre-surround organization. However, there are differences associated with spatial processing: receptive fields are larger in the marmoset than in the macaque, and MT neurons have preferences for lower spatial frequencies. Comparative analysis of anatomical connections show neural projections from several higher-order association areas to marmoset MT, which seem to be absent or reduced in the macaque. This suggests that cognitive processes could influence the activity of marmoset MT cells more directly. Despite a relative reduction in visual acuity, the present knowledge about the anatomy and physiology of MT in the marmoset suggests that simple low-level visual tasks, which are standard in the literature, are well within the capabilities of marmosets, opening the way for comparative studies of perception and cognition in primate brains of different sizes.
01 Jan 2014
TL;DR: Given differences in the positional repertoire of adult and immature golden snub‐nosed monkeys, it is argued that studies of ontogenetic patterns of positional behavior should emphasize what it takes to survive at each life stage rather than whatIt takes to match an adult repertoire.
Abstract: Body mass plays an important role in primate positional behavior and in sexually dimorphic arboreal primatespeciesmayinfluencehowimmatureandadult individuals travelthroughtheforestcanopyand access food resources. In this study, we examined age‐ and sex‐based patterns of positional behavior and substrate utilization in wild golden snub‐nosed monkeys (Rhinopithecus roxellana), an endangered species of Asian colobine. Our results indicated that among all age and sex classes, sitting was the most common feeding and resting posture and during travel, quadrupedal walking was the dominant locomotor behavior. Despite the fact that adult male R. roxellana are reported to exhibit a body mass nearlytwotimesthatofadultfemales,wefoundnosignificantsexdifferencesinthepositionalrepertoire during feeding and traveling. In addition, we found that while infants and juveniles used similar posturalandlocomotorbehaviorsastheiradultcounterparts,youngergoldensnub‐nosedmonkeysmore frequently engaged in risky or escape‐oriented behaviors such as climbing, running, leaping, and forelimb suspension. With increasing age, the use of quadrupedal walking and dropping (downward in‐ air displacement of body mass that does not require hindlimb propulsion) increased and the use of leaping, suspensory postures, and bridging decreased. Finally, given differences in the positional repertoire of adult and immature golden snub‐nosed monkeys, we argue that studies of ontogenetic patterns of positional behavior should emphasize what it takes to survive at each life stage rather than what it takes to match an adult repertoire. Am. J. Primatol. © 2014 Wiley Periodicals, Inc.
TL;DR: In monkeys with long-term unilateral lesions of the dorsal columns at cervical levels, tactile stimulation of the chin showed BOLD activation in the deafferented hand region of contralesional area 3b in the post-central gyrus.
Abstract: Somatosensory cortex of adult primates undergoes topographic reorganization following spinal cord or peripheral nerve injuries. Electrophysiological studies in monkeys show that after chronic lesions of dorsal columns of the spinal cord at cervical levels, there is an expansion of face representation into the deafferented hand region of area 3b of cortex. However, these techniques can sample only a limited portion of the brain. In order to help understand mechanisms of brain reorganization use of noninvasive tools in non-human primate experimental model is important. Use of blood oxygen level dependent-functional magnetic resonance imaging (BOLD-fMRI) to study brain reorganization in non-human primates has been extremely limited. Here, we show that in monkeys with long-term unilateral lesions of the dorsal columns at cervical levels, tactile stimulation of the chin showed BOLD activation in the deafferented hand region of contralesional area 3b in the post-central gyrus. In a monkey with a partial lesion of the dorsal columns, stimulations of both hand and chin activated the partially deafferented hand region. We also show that the somatotopic organization in the non-deafferented ipsilesional somatosensory cortex remained normal.
TL;DR: It is shown that the neonatal marmoset ovary has an extremely immature histological appearance compared with the human ovary, and contains numerous oogonia expressing the pluripotency factors OCT4A, SALL4, and LIN28A (LIN28).
Abstract: Oogonia are characterized by diploidy and mitotic proliferation. Human and mouse oogonia express several factors such as OCT4, which are characteristic of pluripotent cells. In human, almost all oogonia enter meiosis between weeks 9 and 22 of prenatal development or undergo mitotic arrest and subsequent elimination from the ovary. As a consequence, neonatal human ovaries generally lack oogonia. The same was found in neonatal ovaries of the rhesus monkey, a representative of the old world monkeys (Catarrhini). By contrast, proliferating oogonia were found in adult prosimians (now called Strepsirrhini), which is a group of 'lower' primates. The common marmoset monkey (Callithrix jacchus) belongs to the new world monkeys (Platyrrhini) and is increasingly used in reproductive biology and stem cell research. However, ovarian development in the marmoset monkey has not been widely investigated. Herein, we show that the neonatal marmoset ovary has an extremely immature histological appearance compared with the human ovary. It contains numerous oogonia expressing the pluripotency factors OCT4A, SALL4, and LIN28A (LIN28). The pluripotency factor-positive germ cells also express the proliferation marker MKI67 (Ki-67), which has previously been shown in the human ovary to be restricted to premeiotic germ cells. Together, the data demonstrate the primitiveness of the neonatal marmoset ovary compared with human. This study may introduce the marmoset monkey as a non-human primate model to experimentally study the aspects of primate primitive gonad development, follicle assembly, and germ cell biology in vivo.