Primate Species Research Articles

Ecological Requirements for Abundance and Dispersion of Brazilian Yellow Fever Vectors in Tropical Areas

In the Americas, wild yellow fever (WYF) is an infectious disease that is highly lethal for some non-human primate species and non-vaccinated people. Specifically, in the Brazilian Atlantic Forest, Haemagogus leucocelaenus and Haemagogus janthinomys mosquitoes act as the major vectors. Despite transmission risk being related to vector densities, little is known about how landscape structure affects vector abundance and movement. To fill these gaps, we used vector abundance data and a model-selection approach to assess how landscape structure affects vector abundance, aiming to identify connecting elements for virus dispersion in the state of São Paulo, Brazil. Our findings show that Hg. leucocelaenus and Hg. janthinomys abundances, in highly degraded and fragmented landscapes, are mainly affected by increases in forest cover at scales of 2.0 and 2.5 km, respectively. Fragmented landscapes provide ecological corridors for vector dispersion, which, along with high vector abundance, promotes the creation of risk areas for WYF virus spread, especially along the border with Minas Gerais state, the upper edges of the Serra do Mar, in the Serra da Cantareira, and in areas of the metropolitan regions of São Paulo and Campinas.

Experimental Inoculation of Pigs with Monkeypox Virus Results in Productive Infection and Transmission to Sentinels

Monkeypox virus (MPXV) is a re-emerging zoonotic poxvirus responsible for producing skin lesions in humans. Endemic in sub-Saharan Africa, the 2022 outbreak with a clade IIb strain has resulted in ongoing sustained transmission of the virus worldwide. MPXV has a relatively wide host range, with infections reported in rodent and non-human primate species. However, the susceptibility of many domestic livestock species remains unknown. Here, we report on a susceptibility/transmission study in domestic pigs that were experimentally inoculated with a 2022 MPXV clade IIb isolate or served as sentinel contact control animals. Several principal-infected and sentinel contact control pigs developed minor lesions near the lips and nose starting at day 12 through 18 days post-challenge (DPC). No virus was isolated or viral DNA was detected from the lesions; however, MPXV antigen was detected by IHC in tissue from a pustule of a principal infected pig. Viral DNA and infectious virus were detected in nasal and oral swabs up to 14 DPC, with peak titers observed at 7 DPC. Viral DNA was also detected in nasal tissues or skin collected from two principal-infected animals at 7 DPC post-mortem. Furthermore, all principal-infected and sentinel control animals enrolled in the study seroconverted. In conclusion, we provide the first evidence that domestic pigs are susceptible to experimental MPXV infection and can transmit the virus to contact animals.

Urbanization does not increase ‘object curiosity’ in vervet monkeys, but semi-urban individuals selectively explore food related anthropogenic items

Abstract Urban environments expose animals to abundant anthropogenic materials and foods that facilitate foraging innovations in species with opportunistic diets and high behavioural flexibility. Neophilia and exploration tendency are believed to be important behavioural traits for animals thriving in urban environments. Vervet monkeys (Chlorocebus pygerythrus) are one of few primate species that have successfully adapted to urban environments, thus making them an ideal species to study these traits. Using a within-species cross-habitat approach, we compared neophilia and exploration of novel objects (jointly referred to as ‘object curiosity’) between semi-urban, wild, and captive monkeys to shed light on the cognitive traits facilitating urban living. To measure ‘object curiosity’, we exposed monkeys to various types of novel stimuli and compared their approaches and explorative behaviour. Our results revealed differences in the number of approaches and explorative behaviour towards novel stimuli between the habitat types considered. Captive vervet monkeys were significantly more explorative than both semi- urban and wild troops, suggesting that positive experiences with humans and lack of predation, rather than exposure to human materials per se, influence object curiosity. Across habitats, juvenile males were the most explorative age-sex class. This is likely due to males being the dispersing sex and juveniles being more motivated to learn about their environment. Additionally, we found that items potentially associated with human food, elicited stronger explorative responses in semi-urban monkeys than non-food related objects, suggesting that their motivation to explore might be driven by “anthrophilia” i.e., their experience of rewarding foraging on similar anthropogenic food sources. We conclude that varying levels of exposure to humans, predation and pre-exposure to human food packaging explain variation in ‘object curiosity’ in our sample of vervet monkeys.

Ethnoprimatology reveals new extended distribution of critically endangered banded langur Presbytis femoralis (Martin, 1838) in Pahang, Malaysia: Insights from indigenous traditional knowledge and molecular analysis.

The banded langur (Presbytis femoralis) is a critically endangered primate, restricted to Johor, Malaysia, with an estimated population size of less than 500 individuals. Traditionally, distribution studies on this highly threatened primate have relied on conventional methods such as DNA identification, live counting, and camera trapping. However, ethnoprimatology offers an alternative approach to data collection, involving the active participation of indigenous and local communities possessing valuable knowledge and experience with local primate species. This study employed an integrated approach incorporating ethnoprimatology by utilizing pooled local expert opinion, local surveys, interviews, and fecal DNA analysis, resulting in a novel distribution range for the banded langur. The combination of expert opinions revealed this species' most optimistic distribution scenario across Johor and Pahang, inhabiting various ecosystems, including lowland forests, peat swamps, and human-modified landscapes. Further interviews and surveys conducted within the Orang Asli community in Tasik Chini and Tasek Bera have provided additional support for the revised distribution, documenting occurrences of banded langur utilization in indigenous practices, such as food consumption, cultural beliefs, medicinal applications, and craftsmanship. Phylogenetic analysis demonstrated genetic differentiation between populations in Johor and Pahang, with the populations in the southern part of Peninsular Malaysia likely serving as ancestral sources for other populations. Consequently, this study not only elucidated the updated distribution of banded langur through DNA records and direct observations but also established the efficacy of ethnoprimatology as a precursory tool for uncovering the present distribution patterns of other primate species in Malaysia.

Climate and anthropogenic activities threaten two langur species irrespective of their range size

AbstractAimIf species fail to track the pace of climate change, areas of suitable habitat and population size are likely to decline, threatening species survivorship. Here, we incorporated multiple measures of environmental change and species‐specific habitat requirements to assess the responses of two closely related primate species to future changes in climate and habitat conversion. Specifically, we tested whether the comparatively wider‐ranging and Endangered François' langur (Trachypithecus francoisi) is better suited to withstand future anthropogenic habitat conversion and climate change than is the more narrowly ranging and critically endangered white‐headed langurs (T. leucocephalus).LocationChina.MethodsWe used species distribution models (SDMs) models and population viability analyses, and calculated dispersal velocity and biotic velocity, to predict the impact of climate and anthropogenic activity on the distribution and survivorship of two closely related primate species.ResultsWe found that: (1) by the year 2050, the area of suitable habitat for both primate species is expected to decline by 45% to 47%; (2) the population size of François' langurs is expected to increase to 4000 individuals (129%) and the population size of white‐headed langurs is expected to increase to 1400 individuals (133%); (3) biotic velocity, defined as the minimum migration rate required by a species to track its preferred climatic conditions, was 2.84 and 1.48 km/year for François' langurs and white‐headed langurs, respectively; and (4) dispersal velocity, defined as the distance a species has spread over a given period, was 0.82 km/year for both langur species.Main ConclusionsWe demonstrate that despite expected population growth, by the year 2050, habitat contraction and insufficient opportunities for dispersal will likely prevent both primate species from tracking and adjusting to changing climate conditions. Moreover, the more widely ranging species, T. francoisi, was not found to have a survival advantage over the more narrowly ranging species (T. leucocephalus) under future conditions of climate change and continued anthropogenic habitat conversion, resulting in a high risk of extinction for both langur species. The modelling approach used here is robust and can be successfully applied to other threatened animal taxa.

Evolutionarily conserved neural responses to affective touch in monkeys transcend consciousness and change with age

Affective touch-a slow, gentle, and pleasant form of touch-activates a different neural network than which is activated during discriminative touch in humans. Affective touch perception is enabled by specialized low-threshold mechanoreceptors in the skin with unmyelinated fibers called C tactile (CT) afferents. These CT afferents are conserved across mammalian species, including macaque monkeys. However, it is unknown whether the neural representation of affective touch is the same across species and whether affective touch's capacity to activate the hubs of the brain that compute socioaffective information requires conscious perception. Here, we used functional MRI to assess the preferential activation of neural hubs by slow (affective) vs. fast (discriminative) touch in anesthetized rhesus monkeys (Macaca mulatta). The insula, anterior cingulate cortex (ACC), amygdala, and secondary somatosensory cortex were all significantly more active during slow touch relative to fast touch, suggesting homologous activation of the interoceptive-allostatic network across primate species during affective touch. Further, we found that neural responses to affective vs. discriminative touch in the insula and ACC (the primary cortical hubs for interoceptive processing) changed significantly with age. Insula and ACC in younger animals differentiated between slow and fast touch, while activity was comparable between conditions for aged monkeys (equivalent to >70 y in humans). These results, together with prior studies establishing conserved peripheral nervous system mechanisms of affective touch transduction, suggest that neural responses to affective touch are evolutionarily conserved in monkeys, significantly impacted in old age, and do not necessitate conscious experience of touch.

The identification of retro-DNAs in primate genomes as DNA transposons mobilizing via retrotransposition

Background Mobile elements (MEs) constitute a major portion of the genome in primates and other higher eukaryotes, and they play important role in genome evolution and gene function. MEs can be divided into two fundamentally different classes: DNA transposons which transpose in the genome in a “cut-and-paste” style, and retrotransposons which propagate in a “copy-and-paste” fashion via a process involving transcription and reverse-transcription. In primate genomes, DNA transposons are mostly dead, while many retrotransposons are still highly active. We report here the identification of a new type of MEs, which we call “retro-DNAs”, for their combined characteristics of these two fundamentally different ME classes. Methods A comparative computational genomic approach was used to analyze the reference genome sequences of 10 primate species consisting of five apes, four monkeys, and marmoset. Results From our analysis, we identified a total of 1,750 retro-DNAs, representing 748 unique insertion events in the genomes of ten primate species including human. These retro-DNAs contain sequences of DNA transposons but lack the terminal inverted repeats (TIRs), the hallmark of DNA transposons. Instead, they show characteristics of retrotransposons, such as polyA tails, longer target-site duplications (TSDs), and the “TT/AAAA” insertion site motif, suggesting the use of the L1-based target-primed reverse transcription (TPRT) mechanism. At least 40% of these retro-DNAs locate into genic regions, presenting potentials for impacting gene function. More interestingly, some retro-DNAs, as well as their parent sites, show certain levels of expression, suggesting that they have the potential to create more retro-DNA copies in the present primate genomes. Conclusions Although small in number, the identification of these retro-DNAs reveals a new mechanism for propagating DNA transposons in primate genomes without active canonical DNA transposon activity. Our data also suggest that the TPRT machinery may transpose a wider variety of DNA sequences in the genomes.

Resting state networks of awake adolescent and adult squirrel monkeys using ultra-high field (9.4T) functional magnetic resonance imaging.

Resting state networks (RSNs) are increasingly forwarded as candidate biomarkers for neuropsychiatric disorders. Such biomarkers may provide objective measures for evaluating novel therapeutic interventions in nonhuman primates often used in translational neuroimaging research. This study aimed to characterize the RSNs of awake squirrel monkeys and compare the characteristics of those networks in adolescent and adult subjects. Twenty-seven squirrel monkeys (n=12 adolescents [6 male/6 female] ∼2.5 years and n=15 adults [7 male/8 female] ∼9.5 years) were gradually acclimated to awake scanning procedures; whole-brain fMRI images were acquired with a 9.4 Tesla scanner. Group level independent component (ICA) analysis (30 ICs) with dual regression was used to detect and compare RSNs. Twenty ICs corresponding to physiologically meaningful networks representing a range of neural functions, including motor, sensory, reward, and cognitive processes were identified in both adolescent and adult monkeys. The reproducibility of these RSNs was evaluated across several ICA model orders. Adults showed a trend for greater connectivity compared to adolescent subjects in two of the networks of interest: (1) in the right occipital region with the OFC network and (2) in the left temporal cortex, bilateral occipital cortex, and cerebellum with the posterior cingulate network. However, when age was entered into the above model, this trend for significance was lost. These results demonstrate that squirrel monkey RSNs are stable and consistent with RSNs previously identified in humans, rodents, and other nonhuman primate species. These data also identify several networks in adolescence that are conserved and others that may change into adulthood.Significance Statement Functional magnetic resonance imaging procedures have revealed important information about how the brain is modified by experimental manipulations, disease states, and aging throughout the lifespan. Preclinical neuroimaging, especially in nonhuman primates, has become a frequently used means to answer targeted questions related to brain resting-state functional connectivity. The present study characterized resting state networks (RSNs) in adult and adolescent squirrel monkeys; twenty RSNs corresponding to networks representing a range of neural functions were identified. The RSNs identified here can be utilized in future studies examining the effects of experimental manipulations on brain connectivity in squirrel monkeys. These data also may be useful for comparative analysis with other primate species to provide an evolutionary perspective for understanding brain function and organization.

Spatial and temporal dynamics of the primate community in a regenerating forest of the Manu Biosphere Reserve, Peru

Introduction: Amazonian forests with varying degrees of anthropogenic disturbance in the process of natural regeneration harbour many sympatric primate species. However, studies on their usage by primates are still lacking. Objective: To comprehensively study the spatial and temporal dynamics within the primate community in a regenerating forest within the Manu Biosphere Reserve. Methods: Two sets of historical data from Crees Foundation for Manu were analyzed, comprising records from January 2011 to February 2023 and corresponding to data obtained through incidental data and Terrestrial In-line Transects in three types of forest with different degrees of historical disturbance. Results: Lagothrix lagothricha and Ateles chamek showed a preference for less disturbed forests; Plecturocebus toppini, for more disturbed forests; and the other species did not show a clear preference. Regarding vertical stratification, A. chamek, L. lagothricha and Alouatta sara showed a preference for the upper stratum, P. toppini, Saimiri boliviensis and Sapajus macrocephalus showed a preference for the middle and upper strata and Leontocebus weddelli and Aotus nigriceps, for the middle stratum. According to the temporal activity of each species, seven species (A. chamek, S. macrocephalus, S. boliviensis, P. toppini, L. lagothricha, L. weddelli, and A. sara) were observed during the day, four were similar. Conclusions: The primate community varies according to disturbance gradient due to the preferences of some species. The recorded primates make a differentiated use of the vertical strata and most of them show diurnal activity.

Twinning in wild, endangered lion-tailed macaques Macaca silenus in the Anamalai Hills of the Western Ghats, India.

Many primate species show various behavioural and ecological adaptations to provisioning, one of which is the unusual occurrence of twins. Here, we report observations on two pairs of surviving twins in lion-tailed macaques Macaca silenus in the Anamalai Hills of the Western Ghats, India. The Puthuthottam population of lion-tailed macaques has historically been restricted to a rainforest fragment measuring 92ha, situated adjacent to human settlements. Over the last 10years, however, several groups from this population have begun to directly interact with the local human communities, visiting settlements at a rate of 0.52 events/day and exploiting various anthropogenic food resources. We followed and opportunistically collected behavioural ad libitum data on two sets of twins for a year, between March 2019 and March 2020. Both of the mothers were primarily terrestrial, although the mother with the younger set of twins also used the tree canopy and other precarious substrates, such as cables. Although two previous cases of twinning have been reported in this population, one in the late 1990s and one between 2000 and 2002, neither of those sets of twins survived beyond a few weeks, with at least one infant in each pair dying of unknown causes. We discuss, but discount, the possibility that one of the infants in either set of twins was an adoptee. Our observations indicate that some lion-tailed macaque twins can survive under free-ranging conditions if they receive adequate care from their biological mother or another female. Our findings also provide further evidence of increased rates of twinning as a consequence of dietary changes in synanthropic non-human primate populations.

Reduction of bitter taste receptor gene family in folivorous colobine primates relative to omnivorous cercopithecine primates.

Bitter taste perception is important in preventing animals from ingesting potentially toxic compounds. Whole-genome assembly (WGA) data have revealed that bitter taste receptor genes (TAS2Rs) comprise a multigene family with dozens of intact and disrupted genes in primates. However, publicly available WGA data are often incomplete, especially for multigene families. In this study, we employed a targeted capture (TC) approach specifically probing TAS2Rs for ten species of cercopithecid primates with diverse diets, including eight omnivorous cercopithecine species and two folivorous colobine species. We designed RNA probes for all TAS2Rs that we modeled to be intact in the common ancestor of cercopithecids ("ancestral-cercopithecid TAS2R gene set"). The TC was followed by short-read and high-depth massive-parallel sequencing. TC retrieved more intact TAS2R genes than found in WGA databases. We confirmed a large number of gene "births" at the common ancestor of cercopithecids and found that the colobine common ancestor and the cercopithecine common ancestor had contrasting trajectories: four gene "deaths" and three gene births, respectively. The number of intact TAS2R genes was markedly reduced in colobines (25-28 detected via TC and 20-26 detected via WGA analysis) as compared with cercopithecines (27-36 via TC and 19-30 via WGA). Birth or death events occurred at almost every phylogenetic-tree branch, making the composition of intact genes variable among species. These results show that evolutionary change in intact TAS2R genes is a complex process, refute a simple general prediction that herbivory favors more TAS2R genes, and have implications for understanding dietary adaptations and the evolution of detoxification abilities.

Working and impacting local communities as establishing the start of a conservation initiative: American Society of Primatology conservation committee webinar.

Nonhuman primate species currently face human-induced pressures and will continue to face them in the modern landscape. These pressures require conservation projects in primate habitat countries to aid in protection, preservation, and conservation. Though there are several examples of primate conservation projects, starting up an initiative can be a daunting task. The American Society of Primatology (ASP) Conservation Committee hosted a video webinar presenting on the first steps of developing, running and continuing a primate conservation program. Dr. Christopher Shaffer, Rahayu Oktaviani, and Dr. Jill Pruetz presented their early program experiences establishing wild primate conservation projects to educate primatologists around the world. The running themes of the presentations included establishing community, working locally, impacting locally and preparing for the future.

Variation in neophilia in seven primate species.

Neophilia is a measure of individuals' attraction to novelty and is thought to provide important fitness benefits related to the acquisition of information and the ability to solve novel problems. Although neophilia is thought to vary across individuals and species, few studies have made direct comparisons to assess the factors that predict this variation. Here we operationalized neophilia as the probability of interacting with novel objects and compared the response to familiar and novel objects in 53 captive individuals belonging to seven different primate species: chimpanzees (Pan troglodytes), bonobos (Pan paniscus), Sumatran orangutans (Pongo abelii), gorillas (Gorilla gorilla), long-tailed macaques (Macaca fascicularis), tufted capuchin monkeys (Sapajus apella), and Geoffroy's spider monkeys (Ateles geoffroyi). Our results showed that individuals were overall more likely to interact with novel than familiar objects. Moreover, we found no evidence that neophilia varied across individuals depending on their sex, age, and dominance rank. However, macaques were overall less likely to interact with objects (regardless of their novelty), as compared to bonobos, orangutans, gorillas, and capuchin monkeys. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

What makes the ephemeral reward task so difficult?

The ephemeral reward task involves providing subjects with a choice between two distinctive stimuli, A and B, each containing an identical reward. If A is chosen, the reward associated with A is obtained and the trial is over. If B is chosen, the reward associated with B is obtained but A remains, and the reward associated with A can be obtained as well. Thus, the reward-maximizing solution is to choose B first. Although cleaner fish (wrasse) and parrots easily acquire the optimal response by choosing B, paradoxically, several nonhuman primate species, as well as rats and pigeons, do not. It appears that some species do not associate their choice and reward with the second reward. Surprisingly, research in an operant context with pigeons and rats suggests that inserting a delay between the choice and reward facilitates optimal choice. It is suggested that impulsivity may be, in part, responsible for the difficulty of the task. In an attempt to better understand this task, we trained human subjects on an operant version of this task, with and without a brief delay between choice and reward and found that many subjects failed to learn to choose optimally, independent of the delay. Furthermore, performance on this task was not correlated with a task thought to measure impulsivity, the Balloon Analog Risk Task or with the Abbreviated Impulsivity Survey. We concluded that, for humans, the task is confusing because there is no incorrect response, only good and better, and better is not easily discriminated. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

The establishment of a collaborative surveillance program with indigenous hunters to characterize primate health in Southern Guyana.

The consumption of primates is integral to the traditional subsistence strategies of many Indigenous communities throughout Amazonia. Understanding the overall health of primates harvested for food in the region is critical to Indigenous food security and thus, these communities are highly invested in long-term primate population health. Here, we describe the establishment of a surveillance comanagement program among the Waiwai, an Indigenous community in the Konashen Amerindian Protected Area (KAPA). To assess primate health in the KAPA, hunters performed field necropsies on primates harvested for food and tissues collected from these individuals were analyzed using histopathology. From 2015 to 2019, hunters conducted 127 necropsies across seven species of primates. Of this sample, 82 primates (between 2015 and 2017) were submitted for histopathological screening. Our histopathology data revealed that KAPA primates had little evidence of underlying disease. Of the tissue abnormalities observed, the majority were either due to diet (e.g., hepatocellular pigment), degenerative changes resulting from aging (e.g., interstitial nephritis, myocyte lipofusion), or nonspecific responses to antigenic stimulation (renal and splenic lymphoid hyperplasia). In our sample, 7.32% of individuals had abnormalities that were consistent with a viral etiology, including myocarditis and hepatitis. Internal parasites were observed in 53.66% of individuals and is consistent with what would be expected from a free-ranging primate population. This study represents the importance of baseline data for long-term monitoring of primate populations hunted for food. More broadly, this research begins to close a critical gap in zoonotic disease risk related to primate harvesting in Amazonia, while also demonstrating the benefits of partnering with Indigenous hunters and leveraging hunting practices in disease surveillance and primate population health assessment.

Surviving at the highest and coldest: Nutritional and chemical components of fallback foods for Yunnan snub-nosed monkeys.

Fallback foods (FBF), categorized into staple and filler types, are suboptimal food sources chosen by animals in response to a scarcity of preferred food items during specific periods. Using lichens as FBF by Yunnan snub-nosed monkeys (Rhinopithecus bieti) represents a distinctive ecological adaptation and evolutionary development within nonhuman primates. This study delves into the annual dietary choices of the species to address issues, elucidate the nutritional value, and understand the ecological significance of lichens for this primate species, which resides at the highest altitudes and experiences the coldest weather among global primates. The findings reveal that the lichens consumed by the monkeys serve as the staple FBF, with Bryoria spp. and Usnea longissima being the primary dietary species. The former is the preferred choice, providing higher digestible fiber (neutral detergent fiber) levels but lower tannin, fat, ADF, and energy levels. During the dry season, lichens dominate as the monkeys' primary food and nutritional resources. In the wet season, they act as a fundamental food selection rather than an ideal dietary choice, substituting nutrients from fruits, seeds, and leaves. Compared to other Asian colobine counterparts, this species exhibits the highest lichen consumption but the lowest proportions of leaves, flowers, and seeds. This study provides valuable evidence and information for developing or amending conservation strategies and guidelines for the dietary management of captive breeding of monkeys, one of the world's critically endangered primate species.

Comparative kinetics of humans and non-human primates during vertical climbing.

Climbing represents a critical behavior in the context of primate evolution. However, anatomically modern human populations are considered ill-suited for climbing. This adaptation can be attributed to the evolution of striding bipedalism, redirecting anatomical traits away from efficient climbing. Although prior studies have speculated on the kinetic consequences of this anatomical reorganization, there is a lack of data on the force profiles of human climbers. This study utilized high-speed videography and force plate analysis to assess single limb forces during climbing from 44 human participants of varying climbing experience and compared these data with climbing data from eight species of non-human primates (anthropoids and strepsirrhines). Contrary to expectations, experience level had no significant effect on the magnitude of single limb forces in humans. Experienced climbers did, however, demonstrate a predictable relationship between center of mass position and peak normal forces, suggesting a better ability to modulate forces during climbing. Humans exhibited significantly higher peak propulsive forces in the hindlimb compared with the forelimb and greater hindlimb dominance overall compared with non-human primates. All species sampled demonstrated exclusively tensile forelimbs and predominantly compressive hindlimbs. Strepsirrhines exhibited a pull-push transition in normal forces, while anthropoid primates, including humans, did not. Climbing force profiles are remarkably stereotyped across humans, reflecting the universal mechanical demands of this form of locomotion. Extreme functional differentiation between forelimbs and hindlimbs in humans may help to explain the evolution of bipedalism in ancestrally climbing hominoids.

Historical changes in the distribution of the Sichuan golden snub-nosed monkey (Rhinopithecus roxellana) in Sichuan Province, China.

The Sichuan golden snub-nosed monkey (Rhinopithecus roxellana) is a rare and endangered primate species endemic to China. Conducting research on the population distribution changes of the Sichuan golden snub-nosed monkey holds paramount importance for its conservation. Our study represented a comprehensive investigation into the population distribution of the Sichuan snub-nosed monkey by integrating data acquired from field surveys, protected areas, and historical records and using Geographic Information Systems (GIS) to explore changes in distribution across various time periods, including the historical (the Mid-to-Late Pleistocene), recent (1980-2000), and current (2001-2023). The research findings demonstrate a significant shift in the distribution range of the Sichuan golden snub-nosed monkey compared to historical time frames. Notably, between 1980 and 2000, there was a sharp decline in distribution area. Analyses revealed that the southernmost distribution county for the Sichuan golden snub-nosed monkey in Sichuan Province has shifted northward from Huili to Kangding. Furthermore, distribution changes in Sichuan Province are not solely characterized by a reduction in habitat area but also by a decrease in vertical distribution zones. Regions in the northeastern part of Sichuan with elevations below 1000 m, such as Guang'an City, Bazhong City, Dazhou City, and Nanchong City, no longer support the presence of the Sichuan golden snub-nosed monkey. At present, the distribution range is confined to elevations between 1000 and 4000 m in the two major mountain ranges of Qionglai and Minshan. A holistic approach is required to safeguard this species. The establishment of movement corridors can play a critical role in enhancing the overall connectivity of current distribution areas. Additionally, we propose implementing a hierarchical approach to protect current habitats. Spatially differentiated conservation measures should be implemented to prioritize the protection of key habitats while simultaneously monitoring anthropogenic activities in non-key habitats to prevent further fragmentation and isolation of the monkey's distribution areas.

Supplemental Material for Variation in Neophilia in Seven Primate Species

Supplemental Material for Variation in Neophilia in Seven Primate Species

Sex Differences in Sexual Motivation in Humans and Other Mammals: The Role of Conscious and Unconscious Processes.

In self-report questionnaires, men report higher scores than women on variables such as desire for sex, frequency of sexual thoughts, number of sex partners, etc. Based on this, men are considered to have a higher level of sexual motivation than women. However, retrospective self-reports may be unsuitable for estimations of the inherent level of sexual motivation. We review data on automatic (unconsciously controlled) responses and measures of implicit motivation during exposure to sexual stimuli. These responses and measures are inaccessible to willful manipulations and make it possible to determine whether the sex difference in answers to questionnaires is replicated when volitional response manipulations are unlikely. We complement the human data with observations from some rodent and non-human primate species. The attentional resources allotted to stimuli with sexual relevance as well as genital responses to such stimuli are similar in men and women. Measures of implicit motivation also fail to detect any sex difference. Finally, the frequency of masturbation is superior in female infants before the age at which social expectations begin to determine behavior. Neither in rodents nor in non-human primates is there any clear-cut evidence for sex differences in motivation. It seems that males and females are similar with regard to the intensity of sexual motivation. The responses to questionnaires may be affected by social learning of sexual scripts and/or the inferior quality of sexual experiences in women, among other things.