American Journal of Primatology最新文献

{"title":"Route Planning Process by the Endangered Black Lion Tamarin in Different Environmental Contexts","authors":"Felipe Bufalo,&nbsp;Olivier Kaisin,&nbsp;Anne-Sophie de Almeida e Silva,&nbsp;Rodrigo Gonçalves Amaral,&nbsp;Yness Messaoudi,&nbsp;Mirela Alcolea,&nbsp;Eduardo M. Zanette,&nbsp;Gabriel Pavan Sabino,&nbsp;Luca Börger,&nbsp;Laurence Culot","doi":"10.1002/ajp.23702","DOIUrl":"10.1002/ajp.23702","url":null,"abstract":"<div>\u0000 \u0000 <p>Daily, primates take a variety of decisions to establish why, when, and where to move. However, little is known about the factors influencing and shaping primate daily routes. We investigated the decision-making processes linked to route planning in four groups of black lion tamarins (BLT—<i>Leontopithecus chrysopygus</i>). We studied these endangered platyrrhines within four distinct environmental contexts across their natural distribution (i.e., a continuous forest, a 500-ha forest fragment, a 100-ha forest fragment, and a riparian forest). We used the Change Point Test to identify the points of significant direction change (CPs), which can be considered travel goals along BLT daily trajectories and are key components of travel planning. Considering the high importance of fruits and gum in BLT's diet, we predicted that feeding trees would be the main factor shaping their paths (feeding CPs-FCPs). Also, given previous evidence that platyrrhines use landmarks (i.e., characteristic features from the terrain) as nodes in route network systems (i.e., points of intersection connecting habitual route segments), we expected part of CPs to be located close to the intersection points and to be associated with “locomotion” behavior (LCPs). Analyzing 61 daily paths in four forest fragments, our results showed that BLTs planned routes to reach feeding trees, which primarily determined path orientation. As hypothesized, locomotion was the most frequent behavior observed in CPs, but only in the continuous and riparian forests, with LCPs located as close to intersections as FCPs. Interestingly, these two areas presented the most extreme values (i.e., higher and lower values, respectively) in terms of used area, richness of resources and distances traveled between fruit-feeding trees. Our results suggest that BLTs plan daily routes conditional on the environmental context to reach travel goals, likely to maximize route efficiency to reach out of sight feeding trees.</p></div>","PeriodicalId":7662,"journal":{"name":"American Journal of Primatology","volume":"87 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142724768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hepatobiliary Platynosomosis in Black-Tufted Marmosets (Callithrix penicillata): A Lethal Threat for Wildlife and Captive Populations","authors":"Isabel Luana de Macêdo,&nbsp;Davi Emanuel Ribeiro de Sousa,&nbsp;Antonizete dos Reis Souza,&nbsp;Gabriela Rodrigues de Toledo Costa,&nbsp;Marcela Corrêa Scalon,&nbsp;Matheus Almeida Duarte,&nbsp;Giane Regina Paludo,&nbsp;Estevam Guilherme Lux Hoppe,&nbsp;Wilson Junior Oliveira,&nbsp;Pedro Henrique de Oliveira Passos,&nbsp;Alessandro Pecego Martins Romano,&nbsp;Eduardo Mauricio Mendes de Lima,&nbsp;Cristiano Barros de Melo,&nbsp;Márcio Botelho de Castro","doi":"10.1002/ajp.23701","DOIUrl":"10.1002/ajp.23701","url":null,"abstract":"<div>\u0000 \u0000 <p>Helminthic infections, particularly those caused by trematodes, pose a significant health risk to both animals and humans. This study investigates hepatobiliary platynosomosis (HP) caused by <i>Platynosomum illiciens</i> in black-tufted marmosets (<i>Callithrix penicillata</i>) in Central Brazil. Data were retrospectively collected from autopsy records at the Laboratory of Veterinary Pathology and Forensics, University of Brasília, from January 2006 to July 2021. Epidemiological, clinical, and pathological information was analyzed, including comparisons between free-ranging and captive marmosets. A total of 1596 nonhuman primate (NHP) death records were examined, with black-tufted marmosets accounting for 75.6% (1206/1595) of autopsies. HP was identified in 10.8% (131/1206) of these cases. Captive marmosets showed a higher prevalence of HP (49.6%) than free-ranging ones (6.5%). This study revealed a significant seasonal trend, with higher HP prevalence observed during the wet season until the onset of the dry season. Pathological examinations revealed severe liver and bile duct damage in fatal HP cases, including fibrosis, bile duct thickening, and the presence of flukes. Captive marmosets exhibited pronounced clinical signs, such as weight loss and apathy. Morphological and molecular analysis of sampled flukes confirmed <i>P. illiciens</i> infecting the marmosets. These findings underscore the substantial impact of HP on marmoset populations, particularly in captive settings. The high lethality (58% overall; 81.6% in captivity) highlights the need for improved management and preventive measures in captive environments. This study contributes to understanding HP epidemiology, clinical manifestations, and pathological outcomes, underscoring the disease's significance for the health of both free-ranging and captive NHP populations. Our findings also support the need to develop targeted strategies to mitigate the impact of HP on primate species populations.</p></div>","PeriodicalId":7662,"journal":{"name":"American Journal of Primatology","volume":"87 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142708951","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantitative Analysis of the Carpal Tunnel and Its Inner Structures in Primates","authors":"Patrícia Rodríguez,&nbsp;Aroa Casado,&nbsp;Neus Ciurana,&nbsp;Marcel García,&nbsp;Francisco Pastor,&nbsp;Josep Maria Potau","doi":"10.1002/ajp.23700","DOIUrl":"10.1002/ajp.23700","url":null,"abstract":"<p>To explore the anatomical factors potentially involved in the high incidence of carpal tunnel syndrome in humans, we have quantified the anatomical variations of the carpal tunnel and its inner structures in humans, non-hominoid primates (monkeys), and hominoid primates (apes). In specimens of six humans, eight monkeys, and three apes, we assessed the size of the carpal tunnel, the tendons of the digit flexor muscles, and the median nerve. We compared the size of the carpal tunnel normalized by the wrist size, and the size of the median nerve and the tendons of the digit flexors normalized by the size of the carpal tunnel. Differences between humans and monkeys were calculated using the <i>T</i> test or Mann–Whitney <i>U</i> test, as appropriate. Data on the apes were not included in the statistical analyses due to the small sample size. The normalized size of the carpal tunnel was similar in all specimens. The normalized size of the tendons of the digit flexors was smaller in humans, while that of the median nerve was significantly larger. The median nerve was also larger in apes than in monkeys. The relatively larger median nerve observed in humans could suggest a greater vulnerability of the nerve to compression, which could predispose humans to carpal tunnel syndrome. However, the tendons of the digit flexor muscles were smaller in humans, and moreover, the proportional size of the median nerve was similar in apes, leading us to suggest that the factors predisposing humans to carpal tunnel syndrome must be sought beyond anatomical features and may be more closely related to functional or personal parameters.</p>","PeriodicalId":7662,"journal":{"name":"American Journal of Primatology","volume":"87 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ajp.23700","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142674910","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Detecting a Stalker: The Effect of Body Posture, Gaze Direction, and Camouflage Pattern on Predator Detection","authors":"Pedro Z. de Moraes,&nbsp;Pedro Diniz,&nbsp;Daniel M. A. Pessoa","doi":"10.1002/ajp.23699","DOIUrl":"10.1002/ajp.23699","url":null,"abstract":"<div>\u0000 \u0000 <p>The success of a predatory attack is related to how much a predator manages to approach a prey without being detected. Some carnivore mammals use environmental objects (e.g., leaves and branches) as visual obstacles during stalking behavior, allowing them to expose only parts of their bodies while approaching and visual monitoring their prey. Here, we investigate the influence of carnivores’ body postures, gaze direction, and camouflage pattern on their detection by prey. To do so, we photographed taxidermized carnivore models (cougar, ocelot, and lesser grison) in their preserved natural habitats and presented these images to human dichromats (i.e., colourblinds) and trichromats (i.e., normal color vision). Our findings highlight the importance of body outline and gaze as search images during predator detection tasks. We also demonstrate that coat and facial color patterns can camouflage predator's body outline and gaze. This is the first behavioral evidence that the facial coloration of natural predators might mask their gaze to potential prey. Furthermore, we observed that carnivore coat color patterns may serve as an additional cue for trichromats, particularly in hidden carnivore detection tasks that proved to be more challenging for dichromats. Our results show possible strategies that evolved between predator and preys, in which prey make use of body outlines, gaze direction, and coat color to improve predator detection, while predators potentially evolved stalking behavior and body/gaze camouflage as counter strategies to cope with the improvements in prey's perception and conceal their presence.</p></div>","PeriodicalId":7662,"journal":{"name":"American Journal of Primatology","volume":"87 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142646705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Teeth Baring as a Model to Understand Complex Facial Signals in a Tolerant Macaque Species","authors":"Federico Fantoni,&nbsp;Veronica Maglieri,&nbsp;Nicolò Giusti,&nbsp;Chiara Scopa,&nbsp;Virginia Pallante,&nbsp;Antonio Lorenzo Loprete,&nbsp;Elisabetta Palagi","doi":"10.1002/ajp.23697","DOIUrl":"10.1002/ajp.23697","url":null,"abstract":"<p>Facial communication regulates many aspects of social life in human and nonhuman primates. Empirically identifying distinct facial expressions and their underlying functions can help illuminate the evolution of species' communicative complexity. We focused on bared-teeth faces (BTFs), a highly versatile facial expression in the tolerant macaque <i>Macaca tonkeana</i>. By employing a diverse array of techniques (MaqFACS, unsupervised cluster analysis, Levenshtein distance, NetFACS), we quantitatively discriminated two distinct BTFs: bared-teeth (BT) and open mouth bared-teeth (OMBT), and evaluated their distribution across peaceful, playful, and agonistic contexts. Neither BT nor OMBT were context-specific, although BT frequently occurred during peaceful interactions and with low levels of stereotypy. OMBT was highly stereotyped during play, a context involving strong unpredictability. The presence of tongue-protrusion during OMBT was exclusive to peaceful contexts whereas the presence of glabella-lowering during BT and OMBT was specific to agonistic contexts. Hence, BT and OMBT per se are not context-specific, but their contextual relevance hinges on the inclusion of specific key elements. Moving forward, concurrent analyses of stereotypy and specificity should extend beyond our study to encompass other primate and non-primate species, facilitating direct comparisons and revealing how communicative and social complexity coevolve.</p>","PeriodicalId":7662,"journal":{"name":"American Journal of Primatology","volume":"87 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ajp.23697","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142643244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stable Isotopes Analysis of Black Lion Tamarins Reveals Increasing Arthropod Consumption When Fruit Productivity Decreases in Forest Fragments","authors":"Amazone Raskin,&nbsp;Olivier Kaisin,&nbsp;Loïc N. Michel,&nbsp;Benjamin Lejeune,&nbsp;Gilles Lepoint,&nbsp;Rodrigo Gonçalves Amaral,&nbsp;Gabriel Pavan Sabino,&nbsp;Márcio Silva Araújo,&nbsp;Gabriela Cabral Rezende,&nbsp;Fany Brotcorne,&nbsp;Laurence Culot","doi":"10.1002/ajp.23698","DOIUrl":"10.1002/ajp.23698","url":null,"abstract":"<div>\u0000 \u0000 <p>Given the cryptic and elusive nature of prey consumption, quantifying its contribution to the diet of free-ranging primates using behavioral methods is challenging. In this context, the use of carbon and nitrogen-stable isotopes represents a promising alternative approach. Here, we used stable isotope analysis to estimate the proportion of arthropods and fruits in the diet of black lion tamarins (<i>Leontopithecus chrysopygus</i>), an endangered primate endemic to the Brazilian Atlantic Forest. To do so, we ran stable isotope mixing models using isotopic data from hair samples of black lion tamarins living in six forest fragments showing different levels of habitat quality. Furthermore, we ran linear mixed models to assess the influence of habitat quality—fruit productivity (estimated by tree total basal area) and arthropod biomass – and individual characteristics (sex and body mass) on tamarins' δ¹⁵N values (a proxy for trophic position). Our results revealed that arthropods contributed more to black lion tamarins' diet than reported in previous behavioral studies, suggesting that behavioral observations may considerably underestimate the importance of arthropodivory in the diet of arboreal primates. The degree of arthropodivory and frugivory was similar within groups, in line with the strong group cohesion and synchronization of feeding behaviors of this species and supporting the role of site-specific habitat characteristics on dietary choice. Arthropod consumption was higher in areas with lower fruit productivity and did not increase when arthropod biomass increased, suggesting that fruits represent a limiting but preferred resource for this species. These results demonstrate the dietary plasticity of black lion tamarins in areas of lower forest quality, where they manage to compensate low fruit productivity by shifting to a diet richer in arthropods. Considering that this species occurs within a highly fragmented landscape, preserving and protecting small forest patches remains crucial for the conservation of this species.</p></div>","PeriodicalId":7662,"journal":{"name":"American Journal of Primatology","volume":"87 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142612278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Effect of Sampling Schedule on Assessment of Dietary Measures: Evidence From Blue Monkeys (Cercopithecus mitis stuhlmanni)","authors":"Amanda Johnston,&nbsp;Marina Cords","doi":"10.1002/ajp.23696","DOIUrl":"10.1002/ajp.23696","url":null,"abstract":"<div>\u0000 \u0000 <p>Accurately assessing primate diets is important in studies of behavioral ecology and evolution. While previous research has compared sampling methods (scan, focal), we examined how sampling schedule influences accuracy of dietary measures. We define sampling schedule as the combined distribution (random vs. consecutive) and frequency of sampling days within a given month. Under field conditions, time may be required to locate a study group, and we therefore also subtracted 1, 2, or 3 h from the beginning of all non-consecutive days in each sampling schedule to mimic observation time lost to search. From a dense (near daily) 5-year record of feeding behavior derived from focal animal follows of adult females in five wild blue monkey (<i>Cercopithecus mitis</i>) groups, we created data subsets matching various sampling schedules, and compared monthly dietary measures calculated from each subset to those based on the full data set. These measures included (1) the proportion of observation time feeding on fruit, (2) diet composition (three top-ranked food items), (3) species richness of plant diet, (4) Shannon–Wiener diversity index based on plant species, and (5) Holmes–Pitelka index expressing dietary overlap with the previous month. We used generalized linear mixed models to assess how frequency and sampling type (a combination of distribution and hours lost) relate to a subset's deviation from the full data set, where a smaller deviation (or higher chance of matching, for diet composition) implies greater accuracy. For all dietary measures, increasing observation frequency increased accuracy. The response to distribution varied among measures, but sampling types generally differed more at lower frequencies. Deviation varied widely within and between dietary measures, and some sampling schedules resulted in values with large percentage differences from the “full” data. Accordingly, when designing and comparing studies, researchers should consider how sampling schedules may influence the accuracy of the dietary measures of interest.</p></div>","PeriodicalId":7662,"journal":{"name":"American Journal of Primatology","volume":"87 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142612289","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"And Baby Makes Three: Postpartum Changes in Male–Female Affiliative Interactions in White-Faced Capuchins","authors":"Katharine M. Jack,&nbsp;Nelle K. Kulick,&nbsp;Valérie A.M. Schoof,&nbsp;Eva C. Wikberg,&nbsp;Shoji Kawamura,&nbsp;Linda M. Fedigan","doi":"10.1002/ajp.23691","DOIUrl":"10.1002/ajp.23691","url":null,"abstract":"<p>In group-living primates, male investment in infants is highly variable. Previous research on polygynandrous primates found that male care of infants, whether direct or indirect, may be a means to increase offspring survival, increase social status, invest in future mating opportunities, and/or invest in future social or coalition partners, any of which may increase fitness outcomes. Relationships between male white-faced capuchins (<i>Cebus imitator</i>) and infants are highly variable, ranging from neutral to highly affiliative during periods of group stability to lethal during times of instability. We used genetic paternity analysis and behavioral observations to investigate the impact of paternity status, female dominance rank, male dominance rank, and infant sex on changes in rates of affiliation (contact and proximity) between capuchin males and females following the birth of an infant (<i>n</i> = 92 dyads). We used generalized linear mixed models and an information theory approach to select models for averaging. We found that overall rates of male-female affiliation increased following the birth of an infant (contact change: +1.09 ± 2.55%; proximity change: +1.16 ± 3.08%). Infant sex was the only significant explanatory variable; dyads that included males and females who gave birth to male infants experienced a significant increase in their time in contact and proximity in comparison to dyads with females who gave birth to female infants (contact change: <i>p</i> &lt; 0.05 in 2/3 models; proximity change: <i>p</i> &lt; 0.001 in 3/3 models). These findings add to previous data indicating that male capuchins do not recognize their offspring or have the motivation to preferentially invest in their care. We suggest that the observed sex bias may be a form of sex-specific socialization connected to the importance of forming long-term cooperative male bonds that are maintained via male parallel dispersal in this species.</p>","PeriodicalId":7662,"journal":{"name":"American Journal of Primatology","volume":"87 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ajp.23691","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142602786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improving Reproductive Success in Captive Marmosets Through Active Female Choice","authors":"Taylor M. Drazan,&nbsp;Sean P. Bradley,&nbsp;Aikeen M. Jones,&nbsp;Krystal H. Allen-Worthington,&nbsp;Yogita Chudasama","doi":"10.1002/ajp.23689","DOIUrl":"10.1002/ajp.23689","url":null,"abstract":"<p>The recent upsurge in the use of common marmosets (<i>Callithrix jacchus</i>) as a desirable model for high-priority biomedical research has challenged local and global suppliers struggling to provide sufficient numbers of marmosets for large-scale projects. In laboratories, random male-female pairings are often unsuccessful, with intervals of several months before attempting alternate pairings. Here we address this challenge through a behavioral task that promotes self-directed female selection of potential mates to increase the efficiency of breeding in captive marmosets. We created a partner preference test in which nulliparous females (<i>n</i> = 12) had the opportunity to select between two eligible males (<i>n</i> = 23) at a time, in a forced choice test. In this test, both males and females displayed sexual solicitations. However, the females displayed a clear preference for one male by directing affiliative behaviors toward him including proceptive tongue-flicking, approach, and grooming. Her preference remained consistent across three consecutive test sessions. This method resulted in a 2.5-fold improvement in breeding success within 90 days compared to random pairings. This cost-effective and straightforward pairing practice can be used to enhance breeding efficiency in both small and large marmoset colonies.</p>","PeriodicalId":7662,"journal":{"name":"American Journal of Primatology","volume":"87 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ajp.23689","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142602789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Revisiting Linear Enamel Hypoplasia in Cayo Santiago Rhesus Macaques (Macaca mulatta): How a Stress Marker Relates to Environment and Maternal Lineage in a Rare Rhesus Colony With Known Life History.","authors":"Debbie Guatelli-Steinberg, Julianna Watson, Liya Samuel, Emma Showalter, Finn Lerner, Emilie Dixon, Terry B Kensler, George Francis, Elizabeth Maldonado, Luci A P Kohn, Martin Q Zhao, Qian Wang","doi":"10.1002/ajp.23692","DOIUrl":"https://doi.org/10.1002/ajp.23692","url":null,"abstract":"<p><p>Linear enamel hypoplasias (LEHs) are development defects appearing as lines or grooves on enamel surfaces. Forming when physiological stressors disrupt developing teeth, LEHs provide retrospective insight into stress experienced in early development. Here, LEHs in Cayo Santiago rhesus macaques (Macaca mulatta) were observed with respect to decade of birth, whether an individual was transferred from the free-ranging colony to the captive facility during probable crown formation periods, and matriline of birth. It was hypothesized that later decades would exhibit higher prevalence than earlier decades as climatic conditions in Puerto Rico worsened over time. Transfer was expected to affect LEH formation because the process of transfer, and subsequent restriction to captivity, is thought to be stressful. Matriline membership was hypothesized to relate to LEH formation because there is some evidence of a genetic influence on susceptibility to form LEH and because offspring of matrilines of different dominance ranks are known to experience different levels of aggression. Lower third premolars with minimal enamel surface wear were scored for LEH using a digital microscope, while a follow-up analysis of the two matrilines with the most extreme differences in LEH frequency was conducted using enamel surface profiles. Results were: (1) individuals born during the 1990s had significantly greater LEH prevalence than those born in the 1960s, (2) transferred individuals exhibited weak evidence of greater LEH prevalence than nontransferred comparison groups, and (3) matrilines did not differ in LEH expression in the initial or follow-up analysis. Although sample sizes were small for some comparisons, these results suggest that not all decades saw an equal prevalence of LEH, that there might be a small effect of transfer from free-ranging to captive conditions on LEH prevalence that is difficult to detect, and that the matriline into which an individual is born is not related to LEH expression.</p>","PeriodicalId":7662,"journal":{"name":"American Journal of Primatology","volume":" ","pages":"e23692"},"PeriodicalIF":2.0,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142602791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}