American Journal of Primatology

The growing field of comparative thanatology aims to shed light on how and why the understanding of death evolved. Observations across different nonhuman primate species have reported care-taking behaviour of dead infants, but also cannibalism. Various hypotheses have been put forward to explain these infant-directed behaviours, ranging from responses to infantile cues to an understanding of death. To aid comparative analyses and test some of these hypotheses, we report behaviours directed at dead infants in a wild population of Guinea baboons (Papio papio) living in the Niokolo-Koba National Park, Senegal. During 12 years of field observations (2014-2025), 67 infants died before reaching 1 year of age. In 4 cases, we could not establish when the infants had died because the field station was closed due to the COVID-19 pandemic. In 22 of the remaining 63 cases, mothers, but occasionally also other group members, carried, protected, groomed, and dragged dead infants. In 6 cases, cannibalism occurred. None of the mothers expressed any signs of emotional distress in response to infant death. We suggest that a concept of death in Guinea need not be invoked to explain the observed behaviours. Instead, selection appears to have favoured post-mortem caretaking behaviours to avoid abandoning an infant that might temporarily be unresponsive. The lack of infant responses to maternal behaviour and the disintegration of the corpse may drive the transition from perceiving the infants as an object that evokes caretaking to one that resembles food, which ultimately facilitates occurrences of cannibalism.

Human development is marked by extended immaturity, necessitating extended care throughout infancy and childhood, facilitating advanced cognitive, social, and cultural skill acquisition. Parallels of extended development are also present in our closest living relatives, bonobos (Pan paniscus) and chimpanzees (Pan troglodytes). The Self-Domestication Hypothesis (SDH) suggests that human uniqueness stems from selection against aggression. Bonobos are also considered self-domesticated, exhibiting lower aggression and greater social tolerance, which are linked to delayed development and prolonged maternal dependence compared to chimpanzees. However, systematic, quantitative comparisons of the two species developmental patterns are limited and conflicting. This study addressed this gap by examining behavioural development in bonobo and chimpanzee infants aged 0-5.5 years living in two populations (Kokolopori community, Kokolopori Bonobo Reserve, DRC, N=21; Ngogo community, Kibale National Park, Uganda, N=22) in their natural environments. We specifically focused on (i) general behaviours (travel, feeding, grooming), and (ii) spatial independence. By systematically comparing developmental data and using consistent methods, we tested whether bonobo development aligns with SDH predictions. Our results showed similar developmental trajectories, with no species differences concerning ventral riding, nipple contact, or grooming. However, we found species differences regarding travel and proximity patterns, with chimpanzees exhibiting prolonged dorsal riding, bonobos travelling independently more often and maintaining greater distances from their mothers. Age, sibling presence, and maternal parity influenced behavioural patterns, but no sex differences were observed. These findings challenge assumptions of slower bonobo maturation, and highlight the importance of systematic, collaborative research on primate behavioural diversity in natural environments.

Object play - seemingly non-functional interactions with objects - can promote the development of foraging skills, tool use, and behavioral innovation. Among Catarrhine monkeys, it was described in macaques and baboons. Wild geladas, although closely related to baboons, have been described as lacking object play (observed only in captivity) linked to their specialized grazing ecology. Here, we provide the first evidence of both social and solitary object play in a wild gelada population (NOMUs=13) at Debre Libanos (Ethiopia) and compare it with object play in sympatric olive baboons (Nindividuals=42). Notably, immature geladas engaged in object play both socially and solitarily, but the latter case was most frequent also with novel objects introduced by researchers. Solitary object play occurred at levels comparable to those of baboons, challenging previous reports of limited object interest in geladas. This finding aligns with the occurrence of object play in phylogenetically related species and with the retention in wild geladas of arboreal behavior and fruit consumption and hand morphology enhancing fine manipulation. Hence, object play in geladas under certain environmental conditions may reflect a biologically rooted capacity and underscores the importance of ecological variability, as distinct behavioral ecotypes can emerge across different populations of the same species.

ABSTRACTAnthropogenic landscapes are rapidly replacing natural nonhuman primate habitats. Yet, the access to anthropogenic resources on primate biology, health, and fitness remain poorly studied. Given their ubiquity across a range of human impacted landscapes, from cities to national parks, savanna monkeys (Chlorocebus spp.) provide an excellent study system in which to test these effects. We compared body condition and reproductive maturation in vervets (Chlorocebus pygerythrus) inhabiting a private farm in !Gariep Dam, with ample access to anthropogenic foods, and wild-foraging vervets in Soetdoring Nature Reserve, South Africa. Overall, vervets in !Gariep show significantly thicker skin folds, and higher BMI and body mass, than those in Soetdoring, suggesting increased fat deposition. Males in !Gariep have larger relative testis volumes at peri-pubescent ages compared to those in Soetdoring, suggesting early reproductive maturation associated with age-specific increases in body mass. Females from !Gariep showed evidence of an earlier onset of reproduction than those in Soetdoring, based on parity status as assessed by nipple length and evidence of lactation. Parity status at sub-adult dental ages was also strongly associated with body mass. These results are consistent with a positive effect of anthropogenic food-enhancement on body fat deposition, potentially linked to an earlier onset of reproductive maturation. Further investigation into primate responses to cultivated resources will inform our understanding of the broader effects of food enhancement on developmental plasticity.Competing Interest StatementThe authors have declared no competing interest.View Full Text

Chimpanzees, amongst other primates, are characterized by the large variability of habitats they can be found in as well as a large behavioral, sometimes cultural diversity. Such observations have launched a decades-long debate on the roots of behavioral diversity, stressing the need to document this behavioral variability in context, such as by connecting closely related populations through localized analyses. This study presents the first comprehensive description of feeding ecology from the Mwera South chimpanzee (Pan troglodytes schweinfurthii) community in the Bugoma Central Forest Reserve, in Uganda, establishing a valuable baseline for this previously unstudied population and providing a comparative perspective on the populations of Western Uganda and Eastern Democratic Republic of Congo. By employing multiple methodological approaches, including direct observation and fecal analysis, we describe dietary composition, seasonal patterns, and environmental influences on feeding behavior. Characterizing the feeding ecology of this previously unstudied population is critical for examining how ecological factors might influence how feeding patterns evolve depending on resource availability or chimpanzee behavior, in particular by favoring analyses at the regional level. In addition, we can better evaluate to what extent behavioral differences between chimpanzee communities stem from ecological constraints and/or cultural transmission pathways. Our findings suggest that the Bugoma chimpanzees seat at the location of a historic cultural junction, opening a large array of questions about historic movements and cultural diffusion in Eastern chimpanzees.

Social tolerance, defined as the probability of individuals maintaining proximity with minimal aggression, is essential for the functioning of social groups. This study investigates social tolerance in wild vervet monkeys (Chlorocebus pygerythrus), with a focus on co-feeding tolerance. Previous research has highlighted that social tolerance varies both between and within species, influenced by stable group-specific and temporally variable factors. However, it remains unclear how these differences manifest in wild primates, particularly among vervet monkeys. To address this, we employed a novel experimental co-feeding paradigm adapted for field conditions, presenting a fake grass carpet with a fixed density of corn and a plot area proportional to group size to measure group-level co-feeding tolerance. The study was conducted with two habituated groups of wild vervet monkeys at the iNkawu Vervet Project in South Africa. Results revealed significant group differences in co-feeding tolerance despite similarities in the groups demographics and environments. The presence of mothers with infants was associated with higher levels of co-feeding tolerance, though this effect differed by group. These findings highlight the need for further research to elucidate the factors driving group-specific social tolerance levels and the mechanisms behind these differences.

Infant corpse carrying is widely observed in chimpanzees and bonobos, yet its underlying mechanisms remain debated. Analysing 83 published cases using Bayesian mixed-effects models, we show that ICC duration varies with infant age at death, cause of death, and site-level interbirth intervals, with longer carrying following disease-related deaths, older infant age, and slower life histories. These results suggest that variation in infant corpse carrying duration is parsimoniously accounted for by the persistence of maternal behavioural systems being modulated by carrying risk, dyadic bond strength, and life-history context rather than by mothers recognising death as an irreversible biological state. Given the close evolutionary relationship of Pan and Homo, this implies that the complex cognitive frameworks required to recognise deaths finality likely emerged in the hominin lineage after divergence from the Pan-Homo last common ancestor.

Early detection of ovulation and pregnancy in the common marmoset is crucial for reproductive studies, yet hCG kits lack cross-reactivity with marmoset CG, and current methods remain labor-intensive. Here, we developed monoclonal antibodies against marmoset CG and CG{beta}, and established a non-invasive immunochromatographic CG assay. By eliminating invasive blood sampling, this assay supports 3Rs principles and enables practical endocrine monitoring. The assay detected urinary CG surges preceding ovulation, enabling efficient embryo recovery through artificial insemination (75%). Early pregnancy was detected at approximately 17 days post-ovulation. In addition, pregnancy detection in squirrel monkeys suggests conservation of CG features among certain New World primates. Overall, this simple, non-invasive assay provides a practical tool for marmoset research and establishes a foundation for future conservation-oriented reproductive monitoring following appropriate species-specific validation.

The diet of large carnivores is of great interest to conservation managers, as it can reveal the extent of human-carnivore conflict and the impact of carnivores on species of high conservation priority. Metabarcoding of environmental DNA can identify species and is often more reliable in doing so than observational or morphological methods. Metabarcoding is particularly powerful at detecting elusive and rare species and has therefore become a widely applied tool in biodiversity research. Here, we used DNA metabarcoding of fecal samples to determine the diet of spotted hyenas in the Ngorongoro Crater, a protected area in Northern Tanzania surrounded by areas co-inhabited by pastoralists. We assessed which species hyenas preferably consumed over a 24-year period and how frequently they consumed pastoralist livestock and black rhinoceros, a species of high economic value and conservation priority. We further estimated the effects of three key socio-demographic variables - age, social rank, and sex - on the propensity of hyenas to consume livestock. We detected DNA from 20 species in 371 hyena feces. Hyenas preferably consumed blue wildebeest and Grants gazelle. Among the detected species were five domestic species and one wild species that lived in the pastoralist-inhabited areas but not the Crater. This shows that resident Crater hyenas undertake foraging trips to areas surrounding the Crater. DNA of domestic species however was rarely detected (4.1% of 434 detections), and predominantly in feces of old hyenas. This suggests that Crater hyenas rarely consume livestock and that livestock is mostly consumed by hyenas less capable of hunting fleet-footed and powerful wild prey. No DNA of black rhinoceros was detected in any of the samples, suggesting that Crater hyenas do not frequently consume rhinoceros. Our findings suggest that the impact of Crater hyenas on livestock and wildlife of high conservation priority is limited. Our study highlights the potential of DNA metabarcoding to assess the extent of human-carnivore conflict and to guide evidence-based conservation efforts to promote coexistence of carnivores, humans and species of high conservation priority.

Mother-daughter relationships are central to social organization in rhesus macaques, providing the foundation for kin familiarity, affiliative bias, and intergenerational rank inheritance. Understanding how these bonds are structured is therefore important for identifying the processes that contribute to matrilineal cohesion and for anticipating risks of social instability and matriline fragmentation in captive groups. We studied 141 dam-daughter dyads in large, captive groups of rhesus macaques, using generalized linear models to examine associations between demographic variables and affiliative behaviors, and a multivariate clustering approach to characterize how these behaviors combine into distinct relationship types. Our analyses identified eight distinct dam-daughter relationship types defined by combinations of three behavioral domains: grooming, spatial closeness, and agonistic support. Generalized linear models showed that demographic variables had domain-specific effects, with family size, age gaps, and dam age differentially associated with grooming, proximity, and support. These patterns were reflected in the clustering analysis, in which dyads differed not only in overall levels of behavior but also in how behaviors combined within dyads. For example, some dyads exhibited high grooming and support despite low spatial proximity, whereas others showed consistently high expression across all domains. Together, these results demonstrate that dam-daughter bonds are multidimensional and structured through the combination of multiple behavioral domains influenced by demographic and life-history factors. Because these dyads scaffold interactions among close kin, variation in dam-daughter bond structure may influence the development and stability of broader matrilineal relationships. From an applied perspective, considering multiple behavioral domains when assessing social relationships can help identify dyads that may warrant closer monitoring and inform management strategies to support matrilineal cohesion and reduce the risk of social instability in captive groups.

Primate infants depend on their mothers for nursing, transportation, and survival, but also benefit from other behaviours such as contact, protection, and the mother serving as a model for social learning. During infancy, variation in maternal care ("maternal style") can have profound consequences for infant development and survival. We investigated the link between maternal style and infant growth and survival in wild Guinea baboons (Papio papio). This species lives in a tolerant social system with female-biased dispersal. We used data from N = 80 infants to assess variation in maternal style. The final statistical models comprised data from N = 50 infants for the growth analysis based on Parallel Laser Photogrammetry (PLP) measures of forearm length, and N = 63 infants for the survival analysis. To account for heterogeneity in data, we applied a recently established statistical framework that controls for variation in maternal behaviour with infant age. We found only moderate variation among mothers and no evidence for a link between maternal style and infant growth or survival. Neither infant sex, maternal age, nor NDVI variation, a measure later shown to be a poor indicator of food availability, predicted infant growth or survival. We suspect that, in this population living in a habitat with high carrying capacity, disease and predation have greater effects on infant growth and survival than maternal behaviour. Future studies should consider the interplay between infant behaviour and maternal responses in greater detail to better understand variation in early social development.

West African chimpanzees (Pan troglodytes verus) are critically endangered, therefore knowing their ecological needs is necessary to implement proper conservation measures, especially in the face of climatic change. We report here the consumption of soil by wild chimpanzees living in Comoe National Park, Ivory Coast. We confirmed through camera-trap recording that chimpanzees of all ages and both sexes consumed it for several years at least in one community and more occasionally in a second one, aided by leaf-sponge tools. Our results suggest that these chimpanzees living in a savanna-forest mosaic may need minerals supplement, including sodium or/and clay to aid digestion, mainly during the dry season.

Many primates exhibit female philopatry and live in stable, female-bonded social groups. Permanent group fusions are rarely documented in these populations. We present a case study on a fusion of two social groups from a hybrid population of baboons (Papio cynocephalus x P. anubis) living in the Amboseli basin of Kenya. The fusion occurred following a period of increased human-induced mortality in one of the two social groups. After the fusion, females from the smaller group became the lowest ranking. We compared female behavior in the months following the fusion to the behavior of females in groups that had not fused and also compared pre- and post-fusion fitness outcomes. Following the fusion, the groups activity budget and patterns of agonistic interactions were typical for the study population. Females preferred familiar grooming partners for a short period following the fusion; however, after three months, patterns in female grooming were comparable to other groups, indicating rapid social integration. With the caveat that our sample size was limited, we observed no detectable fitness-related costs of group fusion in terms of birth rates or offspring survival, and adult female mortality was low following the fusion. These results demonstrate the flexibility of female baboons in navigating exposure to novel same-sex conspecifics despite a species-typic pattern of female philopatry. Based on this and previous examples of group fusions, we propose that group fusions may be most likely to occur when groups are too small to retain adult males, defend against predators, or compete with other groups.

While it is well established that apes invent or individually learn new gestures, cases of development and use of novel gestures in monkeys are more rarely described. We report a case of a novel, idiosyncratic gesture in a Barbary macaque (Macaca sylvanus) at La Foret des Singes, Rocamadour, France. One adult male, Jomanix, was observed hand-clapping. To our knowledge, hand-clapping has never been described before in this species. To hand-clap, the male briefly shifted his weight onto his legs, lifted his upper body, and clapped both hands together. We recorded 30 instances of hand-clapping. Twenty-five of these hand-claps occurred in combination with other agonistic signals, such as lunges and open mouth threats. Recipients either responded with counter-aggression (N = 9) or a submissive response (N = 16). In five of the 30 events, the context was unclear. These observations suggest that the gesture constitutes an agonistic signal. According to the staff at La Foret des Singes, the hand-clapping may have been copied from staff members who occasionally hand-clap to shoo the animals away from areas where they were not supposed to be, but that notion remains speculative. In the meantime, another subject from the same group reportedly started to hand-clap, but the subject had passed away before we could document the behaviour. The observations show that Jomanix can flexibly combine a novel gesture with other established communicative signals. The hand-clap is goal-directed and fulfils the criteria for first-order intentional communication. This case, as well as anecdotal reports from a Tonkean macaque (Macaca tonkeana) hand-clapping to get attention, reveals greater flexibility in the gestural communication of this genus than previously assumed but also underscores that social learning of the production of communicative gestures occurs rarely in this taxon.

Understanding the distribution of paternity within social groups is critical for testing hypotheses about the evolution of behavior and morphology in primates, but assembling the requisite comparative data is a challenging task. We compiled genetic paternity data from 52 species of wild nonhuman primates along with information about socioecological, morphological, and life history traits that are relevant to understanding what proportion of offspring are sired by primary males (i.e., alpha males in multi-male groups and resident males in single male groups). Our dataset, which currently contains information about 11 primate families and >3,000 individual paternities, is presented as a publicly accessible, living database designed to be updated as new data become available. Using Bayesian regression models, we investigated the role that phylogeny, group composition, and seasonality play in determining primary males paternity share, and assessed the relative share of paternities obtained by non-primary residents versus extra-group males. First, we found that phylogeny has a detectable but relatively modest influence on primary males paternity share. Species-level differences explained roughly 35-40% of variation in primary males paternity share, and of that interspecific variation, [~]50-70% was attributable to shared phylogenetic history. Second, group composition strongly predicted paternity share outcomes. Primary males in single-male/multi-female groups obtained the highest share of paternity ([~]80%), while those in multi-male groups had the lowest ([~]60%), though there was substantial variation within each category. Pair-living animals showed a striking split: males in cohesive pairs sired [~]90% of offspring, while those in dispersed pairs sired only [~]55%. Contrary to expectations, reproductive seasonality did not predict primary males paternity share in any group type. Finally, when primary males in multi-male groups lost paternities, [~]75% of losses were to other resident males. Overall, [~]5-15% of offspring in these groups were sired by extra-group males. Our results largely confirm earlier findings based on smaller datasets, but also show that the relationship between social organization and paternity is more complicated than simple categorical predictions suggest. We discuss the gap between the data that would ideally be available for testing these hypotheses versus what currently exists, with hopes that our living database can help close this gap over time.

Chimpanzee pant-hoots are frequently produced long-distance vocalisations that serve a number of social functions, such as to indicate coordinate travelling, food discovery, or social status. Calling often triggers replies by others, offering potential for some form of group-level decision-making through vocal exchanges. However, despite important physiological and social differences between male and female chimpanzees, pant-hoot research has traditionally focused on males, with very little known about female use. To address this gap, we collected all-occurrence behavioural data from wild adult female and male Eastern chimpanzees (Pan troglodytes schweinfurthii) in two communities in the Budongo Forest Reserve, Uganda. We show that females pant-hooted regularly, but less frequently than males and, when they did so, mostly in response to others. Response pant- hoots were more common than initiating pant-hoots in both sexes (females: 90.1%; males: 69.5%), and male and female chimpanzees responded to pant-hoots heard at a similar rate (females: 14.1%, males excluding alpha: 15.8%). Both sexes were more likely to respond to pant-hoots from within their own party, but this effect was stronger for females. The likelihood of male chimpanzees pant-hooting in response was inhibited in larger party sizes, while females response pant-hoots were not. Finally, female response pant-hoots were less common during periods of maximal oestrous as compared to other stages of their reproductive cycle. Overall, our findings demonstrate that response pant-hoots are subject to social factors, such as within-sex social competition and between-sex reproductive strategies, which affect male and female chimpanzees in different ways, a further demonstration of the high degree of audience awareness in this primate species. HighlightsO_LIChimpanzees use pant-hoots in both sex-specific and sex-non-specific ways C_LIO_LIIndividual and social factors impact likelihood of pant-hoot production C_LIO_LIOur findings suggest pant-hoots are important flexible elements of vocal behaviour for male and female chimpanzees. C_LI

For nonhuman primates living in anthropogenic areas, predation by larger predators is relatively rare. However, smaller predators such as free-ranging as well as domesticated dogs can shape the socioecology of urban nonhuman primates, directly by attacking and predating upon them, or indirectly by modifying their activity patterns. Here, we describe 3 (2 potentially lethal) cases of dog attacks on adult rhesus macaques inhabiting an anthropogenic landscape in Northern India, and the circumstances surrounding these incidents. We discuss the importance of considering the presence of dogs while studying nonhuman primate populations across the anthropogenic gradient and its implications for understanding how human presence can directly and indirectly affect predator-prey relationship in these areas, as well as its potential role in modifying group social dynamics as well as in transmission of zoonotic agents.

Primate extractive foraging requires years of dedicated learning. Throughout this period, learners peer at conspecifics engaging in the behaviour ("models"), interacting with the model and their tools, and sometimes stealing the freshly extracted resource. This also corresponds to an extended period of tolerance from the models. Yet the long-term effect of variation in experiences during this period on the technological efficiency of individuals is unknown for primate tool use, and no research has assessed the role of both the learner and the model(s) in generating individual differences. Using >680 hours of video spanning 25 years, we assessed whether experiences during the stone tool use social learning period ("early learning period"; ages 0-5) predicted the post-early learning period (ages 6+) technological efficiency in wild chimpanzees in Bossou, Guinea. We found that learners varied in how frequently they peered at the models whole nut-cracking bouts, how many learning opportunities their mothers presented, and the amount of tolerance and intolerance they experienced from all selected models. Learners who experienced more intolerance became less efficient tool users, whereas learners who were exposed to more social learning opportunities and tolerance became more efficient. Peering at the whole nut-cracking bout decreased subsequent efficiency, hinting at learners acquiring less efficient cultural components of the behaviour. Our findings highlight the role of social learning in the acquisition of stone tool use and support the view that social learning opportunities within a tolerant environment are key in explaining the emergence and maintenance of complex forms of primate technology. Significance StatementThe capacity and inclination to learn from others, along with social learning opportunities provided by tolerant groupmates, are thought to have enabled the evolution of technology in primates, including hominins. The influence of the learning period on long-term individual variation in technological efficiency remains unknown for non-human primates but has significant implications for cultural transmission and evolution. We provide longitudinal support for the hypothesis that exposure to social learning opportunities during development predicts subsequent technological efficiency. Moreover, we show that low amounts of intolerance, not just general tolerance, is key in the ontogeny of technological efficiency. Finally, we find aspects of behavioural acquisition relating to accurate transmission of cultural traits rather than to learning to use tools efficiently.

Allostatic load refers to the wear and tear of the organism associated with the repeated activation of mechanisms that allow for homeostasis. Although allostasis (i.e., maintaining stability through change) is achieved through the orchestration of multiple systems, assessments of allostatic load in wildlife have usually relied on the measurement of single or few physiological mediators. In the present study, we aimed at constructing an allostatic load index (ALI) for male mantled howler monkeys (Alouatta palliata) based on seven physiological mediators (C-peptide, triiodothyronine, glucocorticoids, testosterone, amount of activity, foraging effort, and participation in agonistic interactions). We then examined if variation in this ALI was associated with social, ecological, and abiotic challenges. For five years, we studied ten adult males belonging to two groups. We assessed physiological mediators via behavioral observations (3,364 hours of samplings), and both urine (1,500 assayed samples) and fecal (1,500 assayed samples) sampling. We calculated an ALI based on mediator specific risk scores. Seasonality, encounters with extragroup males, mating, and centrality were positively related with male allostatic load, though only the first two had significant effects on ALI. ALI reflected the physiological and behavioral responses of males to social, ecological, and abiotic challenges. It remains for future research to determine if the observed trends correspond to normal fluctuations in mechanisms that allow male mantled howler monkeys to cope with their environment.

Mammalian mothers provide behavioral and physiological signals that offspring use to calibrate development in relation to maternal resources and environmental cues. Infants respond selectively as they prioritize certain developmental systems over others, creating developmental tradeoffs between competing biological systems. Here, we investigate the influence of maternal capital ("investment capacity") on the growth and development of their infants in wild olive baboons (Papio anubis) from Laikipia, Kenya. We posit that maternal capital is influenced by a mothers own early life experiences (e.g., drought, maternal loss) and her current life experiences (e.g., dominance rank, food availability), and is signaled to offspring via maternal effort (i.e., nursing and carrying time) and glucocorticoids. We used behavioral data on 40 infants (43% female) in the first year of life to quantify maternal effort, infant play, and infant independence (i.e., frequency of infant departures from mother). We matched these behavioral data with maternal fecal glucocorticoid measures from lactating mothers, and infant growth measures assessed via photogrammetry. Signals of low maternal capital predicted lower rates of infant play, less behavioral independence, and slower growth. There was a negative relationship between the rate of social contact play and growth rate, indicating a developmental tradeoff. Males were more sensitive than females to some of the maternal signals measured in our study. These results add to a growing body of evidence demonstrating that maternal behavioral and physiological signals shape infant development.