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Science Advances Oct 2023Humans are strategic cooperators; we make decisions on the basis of costs and benefits to maintain high levels of cooperation, and this is thought to have played a key...
Humans are strategic cooperators; we make decisions on the basis of costs and benefits to maintain high levels of cooperation, and this is thought to have played a key role in human evolution. In comparison, monkeys and apes might lack the cognitive capacities necessary to develop flexible forms of cooperation. We show that Guinea baboons () can use direct reciprocity and partner choice to develop and maintain high levels of cooperation in a prosocial choice task. Our findings demonstrate that monkeys have the cognitive capacities to adjust their level of cooperation strategically using a combination of partner choice and partner control strategies. Such capacities were likely present in our common ancestor and would have provided the foundations for the evolution of typically human forms of cooperation.
Topics: Animals; Humans; Papio papio; Hominidae; Cooperative Behavior
PubMed: 37889969
DOI: 10.1126/sciadv.adi5282 -
American Journal of Primatology Jan 2024Milk composition is a fundamental aspect of mammalian reproduction. Differences in milk composition between species may reflect phylogeny, dietary ecology, lactation...
Milk composition is a fundamental aspect of mammalian reproduction. Differences in milk composition between species may reflect phylogeny, dietary ecology, lactation strategy, and infant growth patterns, but may also vary within a species due to maternal body condition. This study presents the first published data on milk macronutrient composition of southern pig-tailed macaques (Macaca nemestrina) and compares the results with data on two other Cercopithecine species. Milk samples were obtained from five dams at 10- and 14-weeks postparturition. Macronutrient composition was determined at the Smithsonian's National Zoo and Conservation Biology Institute using proven methods developed over 30 years. On average (±SEM), the milk contained 83.9 ± 0.4% water, 6.7 ± 0.4% fat, 7.6 ± 0.1% sugar, 1.8 ± 0.1% protein, and 0.22 ± 0.01% mineral content. The Ca:P ratio was 1.8; concentrations of Ca and protein were correlated. Mean gross energy was 1.02 ± 0.03 kcal/g with most of the energy coming from fat (59.6 ± 1.5%), followed by sugar (29.9 ± 1.4%) and protein (10.5 ± 0.5%). The milks at 14 weeks of infant age were higher in energy than the milks at 10 weeks, with an increase in energy from fat (p = 0.005) and decrease in energy from sugar (p = 0.018). The energy from protein did not change (p = 0.272). Compared to captive rhesus macaque (Macaca mulatta) and olive baboon (Papio anubis) milk assayed by identical methods, captive pig-tailed macaque milk was higher in energy, but after accounting for the higher milk energy there was no difference in the proportions of milk energy from protein, fat, and sugar. The captive pig-tailed dams were significantly heavier than reported values for wild pig-tailed macaques, suggesting high body condition. High body condition in captive Cercopithecines appears to result in milk higher in energy, with more energy coming from fat and less from sugar. However, variation in the proportion of milk energy from protein in captive Cercopithecine milks appears relatively constrained.
Topics: Animals; Female; Macaca mulatta; Macaca nemestrina; Milk; Nutrients; Sugars
PubMed: 37876290
DOI: 10.1002/ajp.23570 -
Developmental Psychobiology Nov 2023Among human and nonhuman primates, mutual eye gaze (MEG) and gaze following are believed to be important for social cognition and communicative signaling. The goals of...
Among human and nonhuman primates, mutual eye gaze (MEG) and gaze following are believed to be important for social cognition and communicative signaling. The goals of this study were to examine how early rearing experiences contribute to individual variation in MEG and to examine the potential role of genetic factors underlying this variation. Subjects included 93 female and 23 male baboons (Papio anubis) ranging from 3 to 20 years of age. Within the sample, there were 55 mother-reared (MR) and 61 nursery-reared (NR) baboons. MEG was assessed in four 60-s test sessions. For each session, the duration, frequency, and bout length were recorded. Mean values were then calculated for each individual from the four sessions. A multivariate analysis of covariance revealed an overall significant main effect for rearing. Subsequent univariate analyses revealed significant rearing effects on mean bout length, but not mean duration or mean frequency, with MR baboons having longer bout lengths compared to NR baboons. Furthermore, mean bout length was found to be significantly heritable. These results indicate that rearing experiences, and to a small extent, genetic factors, affect patterns of mutual eye gaze - in particular, bout length. These results differ from previous findings in MR and NR chimpanzees, further suggesting that rearing may impact MEG in a species-specific manner that reflects the function of gaze in different primate species.
Topics: Humans; Animals; Male; Female; Papio anubis; Fixation, Ocular; Papio; Primates
PubMed: 37860908
DOI: 10.1002/dev.22420 -
Journal of Medical Primatology Dec 2023Endometriosis is the presence of endometrium-like tissue outside the uterine cavity. An experimental model of endometriosis has been created in the baboon by the...
BACKGROUND
Endometriosis is the presence of endometrium-like tissue outside the uterine cavity. An experimental model of endometriosis has been created in the baboon by the transcervical collection and laparoscopic inoculation of menstrual endometrium. Macaques are the preferred model for pharmaceutical development, but the complex anatomy of the macaque cervix makes the baboon method impractical. In this work, we sought to validate a surgical approach for creating endometriosis in macaques.
METHODS
Menstrual endometrium was collected via laparoscopic intrauterine puncture and transferred to the peritoneal cavity. We repeated this procedure during three menstruations. Endometriotic tissue was identified during laparoscopy, collected, and characterized by immunohistochemistry.
RESULTS
Sham surgery-treated animals (n = 3) failed to develop endometriosis. We identified red, powder burnt, and white lesions in 13/14 of the treated animals; the stroma of the red lesions stained positive for ovarian steroid receptors.
CONCLUSION
This surgical technique can reliably create hormone-responsive endometriosis in macaques for therapeutic studies.
Topics: Female; Animals; Endometriosis; Macaca mulatta; Endometrium; Laparoscopy; Papio
PubMed: 37849073
DOI: 10.1111/jmp.12681 -
Evolutionary Anthropology Dec 2023Chimpanzees regularly hunt and consume prey smaller than themselves. It seems therefore likely that early hominins also consumed small vertebrate meat before they... (Review)
Review
Chimpanzees regularly hunt and consume prey smaller than themselves. It seems therefore likely that early hominins also consumed small vertebrate meat before they started using and producing stone tools. Research has focused on cut marks and large ungulates, but there is a small body of work that has investigated the range of bone modifications produced on small prey by chimpanzee mastication that, by analogy, can be used to identify carnivory in pre-stone tool hominins. Here, we review these works along with behavioral observations and other neo-taphonomic research. Despite some equifinality with bone modifications produced by baboons and the fact that prey species used in experiments seldom are similar to the natural prey of chimpanzees, we suggest that traces of chimpanzee mastication are sufficiently distinct from those of other predators that they can be used to investigate mastication of vertebrate prey by early hominins.
Topics: Animals; Hominidae; Pan troglodytes; Carnivory; Mammals; Vertebrates; Papio
PubMed: 37844154
DOI: 10.1002/evan.22006 -
Animals : An Open Access Journal From... Oct 2023Besides living as a free-ranging primate in the horn of Africa and the Arabian Peninsula, the hamadryas baboon has an important place in zoos and can be found in...
Besides living as a free-ranging primate in the horn of Africa and the Arabian Peninsula, the hamadryas baboon has an important place in zoos and can be found in biomedical research centers worldwide. To be valuable as a non-human primate laboratory model for man, its anatomy should be portrayed in detail, allowing for the correct interpretation and translation of obtained research results. Reviewing the literature on the use of the baboon in biomedical research revealed that very limited anatomical works on this species are available. Anatomical atlases are incomplete, use archaic nomenclature and fail to provide high-definition color photographs. Therefore, the skeletons of two male hamadryas baboons were prepared by manually removing as much soft tissues as possible followed by maceration in warm water to which enzyme-containing washing powder was added. The bones were bleached with hydrogen peroxide and degreased by means of methylene chloride. Photographs of the various bones were taken, and the anatomical structures were identified using the latest version of the Nomina Anatomica Veterinaria. As such, the present article shows 31 annotated multipanel figures. The skeleton of the hamadryas baboon generally parallels the human skeleton, but some remarkable differences have been noticed. If these are taken into consideration when evaluating the results of experiments using the hamadryas baboon, justified conclusions can be drawn.
PubMed: 37835730
DOI: 10.3390/ani13193124 -
Molecular Imaging and Biology Dec 2023PET imaging using [C]metoclopramide revealed the importance of P-glycoprotein (P-gp, ABCB1) in mediating the brain-to-blood efflux of substrates across the blood-brain...
PURPOSE
PET imaging using [C]metoclopramide revealed the importance of P-glycoprotein (P-gp, ABCB1) in mediating the brain-to-blood efflux of substrates across the blood-brain barrier (BBB). In this work, the elimination rate constant from the brain (k), calculated from dynamic PET images without the need for arterial blood sampling, was evaluated as an outcome parameter for the interpretation of [C]metoclopramide PET data.
PROCEDURES
k parameter was obtained by linear regression of log-transformed brain time-activity curves (TACs). k values (h) obtained under baseline conditions were compared with values obtained after complete P-gp inhibition using tariquidar in rats (n = 4) and baboons (n = 4) or after partial inhibition using cyclosporine A in humans (n = 10). In baboons, the sensitivity of k to measure complete P-gp inhibition was compared with outcome parameters derived from kinetic modeling using a 1-tissue compartment model (1-TCM). Finally, k-maps were generated in each species using PMOD software.
RESULTS
The linear part of the log-transformed brain TACs occurred from 10 to 30 min after radiotracer injection in rats, from 15 to 60 min in baboons, and from 20 to 60 min in humans. P-gp inhibition significantly decreased k values by 39 ± 12% in rats (p < 0.01), by 32 ± 6% in baboons (p < 0.001), and by 37 ± 22% in humans (p < 0.001). In baboons, P-gp inhibition consistently decreased the brain-to-plasma efflux rate constant k (36 ± 9%, p < 0.01) leading to an increase in the total brain volume of distribution (V, 101 ± 12%, p < 0.001). In all studied species, brain k-maps displayed decreased P-gp-mediated efflux across the BBB.
CONCLUSIONS
k of [C]metoclopramide provides a simple outcome parameter to describe P-gp function in the living brain when arterial input function data are unavailable, although less sensitive than V. k-maps represent easy to compute parametric images reflecting the effect of P-gp on [C]metoclopramide elimination from the brain.
Topics: Humans; Rats; Animals; Blood-Brain Barrier; ATP Binding Cassette Transporter, Subfamily B, Member 1; Metoclopramide; Brain; ATP Binding Cassette Transporter, Subfamily B; Positron-Emission Tomography; Papio
PubMed: 37801196
DOI: 10.1007/s11307-023-01864-z -
The American Naturalist Oct 2023AbstractOver the past 50 years, a wealth of testable, often conflicting hypotheses have been generated about the evolution of offspring sex ratio manipulation by...
AbstractOver the past 50 years, a wealth of testable, often conflicting hypotheses have been generated about the evolution of offspring sex ratio manipulation by mothers. Several of these hypotheses have received support in studies of invertebrates and some vertebrate taxa. However, their success in explaining sex ratios in mammalian taxa-especially in primates-has been mixed. Here, we assess the predictions of four different hypotheses about the evolution of biased offspring sex ratios in the baboons of the Amboseli basin in Kenya: the Trivers-Willard, female rank enhancement, local resource competition, and local resource enhancement hypotheses. Using the largest sample size ever analyzed in a primate population ( offspring), we test the predictions of each hypothesis. Overall, we find no support for adaptive biasing of sex ratios. Offspring sex is not consistently related to maternal dominance rank or biased toward the dispersing sex, nor is it predicted by group size, population growth rates, or their interaction with maternal rank. Because our sample size confers power to detect even subtle biases in sex ratio, including modulation by environmental heterogeneity, these results suggest that adaptive biasing of offspring sex does not occur in this population.
Topics: Animals; Female; Papio; Papio cynocephalus; Sex Ratio; Primates; Mammals
PubMed: 37792922
DOI: 10.1086/725886 -
American Journal of Biological... Jan 2024This brief communication documents the prevalence of maxillary central incisor talon cusps in Cayo Santiago rhesus monkeys (Macaca mulatta) and assesses whether talon...
OBJECTIVES
This brief communication documents the prevalence of maxillary central incisor talon cusps in Cayo Santiago rhesus monkeys (Macaca mulatta) and assesses whether talon cusp presence occurs at equivalent frequencies across matrilines.
MATERIALS AND METHODS
The data on cusp presence vs. absence were analyzed by logistic regression in 170 monkeys (82 females, 78 males) from seven different matrilines. Sample sizes per matriline ranged from 10 to 42. Observations of talon cusps were blind with respect to matriline and sex.
RESULTS
Talon cusps were present in 9.4% of the sample. By matriline, cusp frequencies ranged from 0%-Matrilines 073 and 106%-to 19.1% in Matriline 076. The frequency of the talon cusp in Matriline 076 was significantly greater than the frequency of the cusp in the remainder of the sample. There was no statistically significant difference in the frequency of the talon cusp by sex.
CONCLUSIONS
This study suggests that the talon cusp in rhesus monkeys, as in humans and baboons, is a rare trait. Elevated prevalence of the talon cusp in Matriline 076 suggests the possibility of a genetic influence on talon cusp expression.
Topics: Male; Female; Animals; Humans; Macaca mulatta; Tooth, Supernumerary; Incisor; Prevalence; Papio
PubMed: 37787449
DOI: 10.1002/ajpa.24855 -
BMJ Open Quality Sep 2023In low-to-middle-income countries (LMIC), the orthogeriatric model of care is still in its early stages of development. This study describes the initial results of the...
INTRODUCTION
In low-to-middle-income countries (LMIC), the orthogeriatric model of care is still in its early stages of development. This study describes the initial results of the first online fragility hip fracture database to be setup in the Philippines using a modified minimum common dataset to generate outcomes data based on current hospital practices.
METHODS
A multicentre prospective cohort study among 12 Philippine hospitals was conducted from June 2020 to February 2021. Thirty-day mortality, morbidity and mobility were measured. Significant factors associated with mortality were determined.
RESULTS
158 elderly patients with fragility hip fractures were included in the study. Nine patients (5.7%) were confirmed or suspected to have COVID-19 infection. Median time of injury to admission was at least 3 days (IQR: 1.0-13.7). Overall, 80% of patients underwent surgical intervention with a median time from admission to surgery of at least 5 days (IQR: 2.5-13.6). Thirty-day mortality and morbidity rates for acute fragility fractures were 3.7%. Factors significantly associated with early mortality were poor prefracture mobility, COVID-19 infection, radiograph of the abnormal chest and conservative treatment. Non-surgical patients had no functional mobility or were wheelchair users and had a significantly higher morbidity rate than surgically treated patients (13.6% vs 1.8%; p=0.031).
CONCLUSION
Despite treatment delays unique to an LMIC, short-term outcomes remain favourable for non-COVID-19 fragility hip fracture patients treated with surgery. Prompt admission and multidisciplinary care for elderly hip fracture patients while maintaining protective measures for COVID-19 infection control are recommended. The quality of data collected illustrates how this online database can provide a framework for a sustainable audit or registry as well as provide a platform for the introduction of orthogeriatric concepts at a multiregional scale.
Topics: Humans; Aged; Prospective Studies; Pandemics; COVID-19; Hip Fractures; Hospitalization
PubMed: 37783523
DOI: 10.1136/bmjoq-2023-002299