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Intergroup aggression often results in the production of public goods, such as a safe and stable social environment and a home range containing the resources required to survive and reproduce. We investigate temporal variation in intergroup aggression in a growing population of colobus monkeys (Colobus vellerosus) to ask a novel question: "Who stepped-up to produce these public goods when doing so became more difficult?". Both whole-group encounters and male incursions occurred more frequently as the population grew. Males and females were both more likely to participate in whole-group encounters when monopolizable food resources were available, indicating both sexes engaged in food defence. However, only females increasingly did so as the population grew, suggesting that it was females who increasingly produced the public good of home range defence as intergroup competition intensified. Females were also more active in male incursions at high population densities, suggesting they increasingly produced the public good of a safe and stable social environment. This is not to say that males were chronic free-riders when it came to maintaining public goods. Males consistently participated in the majority of intergroup interactions throughout the study period, indicating they may have lacked the capacity to invest more time and effort.
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Agresión , Colobus , Crecimiento Demográfico , Animales , Femenino , Masculino , Colobus/fisiología , Conducta Competitiva/fisiología , Conducta Social , Conducta AnimalRESUMEN
The gut microbiota of group-living animals is strongly influenced by their social interactions, but it is unclear how it responds to social instability. We investigated whether social instability associated with the arrival of new males and challenges to the alpha male position could explain differences in the gut microbiota in adult female Colobus vellerosus at Boabeng-Fiema, Ghana. First, we used a data set collected during May-August 2007 and May 2008-2009 that consisted of (i) 50 fecal samples from adult females in eight social groups for V4 16S rRNA sequencing to determine gut microbiota composition, and (ii) demographic and behavioral data ad libitum to determine male immigration, challenges to the alpha male position, and infant births and deaths. Sørensen and Bray-Curtis beta diversity indices (i.e., between-sample microbiota variation) were predicted by year, alpha male stability, group identity, and age. Next, we used a more detailed behavioral data set collected during focal observations of adult females in one group with a prolonged alpha male takeover and three cases of infant loss, to create 12-month versus 3-month 1-m proximity networks that preceded and overlapped the gut microbiome sampling period in that group. The long versus short-term networks were not correlated, suggesting temporal variation in proximity networks. In this group, beta diversity among the five adult females was predicted by similarity in infant loss status and short-term (rather than yearly) 1-m proximity ties. Although the mechanism driving this association needs to be further investigated in future studies, our findings indicate that alpha male takeovers are associated with gut microbiota variation and highlight the importance of taking demographic and social network dynamics into account.
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Colobus , Heces , Microbioma Gastrointestinal , Animales , Femenino , Masculino , Colobus/microbiología , Colobus/fisiología , Heces/microbiología , ARN Ribosómico 16S/análisis , ARN Ribosómico 16S/genética , Ghana , Conducta SocialRESUMEN
Proposed mechanisms of zoonotic virus spillover often posit that wildlife transmission and amplification precede human outbreaks. Between 2006 and 2012, the palm Raphia farinifera, a rich source of dietary minerals for wildlife, was nearly extirpated from Budongo Forest, Uganda. Since then, chimpanzees, black-and-white colobus, and red duiker were observed feeding on bat guano, a behavior not previously observed. Here we show that guano consumption may be a response to dietary mineral scarcity and may expose wildlife to bat-borne viruses. Videos from 2017-2019 recorded 839 instances of guano consumption by the aforementioned species. Nutritional analysis of the guano revealed high concentrations of sodium, potassium, magnesium and phosphorus. Metagenomic analyses of the guano identified 27 eukaryotic viruses, including a novel betacoronavirus. Our findings illustrate how "upstream" drivers such as socioeconomics and resource extraction can initiate elaborate chains of causation, ultimately increasing virus spillover risk.
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Animales Salvajes , Quirópteros , Conservación de los Recursos Naturales , Animales , Quirópteros/virología , Uganda , Animales Salvajes/virología , Heces/virología , Colobus/virología , Virus/aislamiento & purificación , Virus/genética , Virus/clasificación , Pan troglodytes/virologíaRESUMEN
OBJECTIVES: Despite qualitative observations of wild primates pumping branches before leaping across gaps in the canopy, most studies have suggested that support compliance increases the energetic cost of arboreal leaping, thus limiting leaping performance. In this study, we quantified branch pumping behavior and tree swaying in wild primates to test the hypothesis that these behaviors improve leaping performance. MATERIALS AND METHODS: We recorded wild colobine monkeys crossing gaps in the canopy and quantitatively tracked the kinematics of both the monkey and the compliant support during behavioral sequences. We also empirically measured the compliance of a sample of locomotor supports in the monkeys' natural habitat, allowing us to quantify the resonant properties of substrates used during leaping. RESULTS: Analyses of three recordings show that adult red colobus monkeys (Piliocolobus tephrosceles) use branch compliance to their advantage by actively pumping branches before leaping, augmenting their vertical velocity at take-off. Quantitative modeling of branch resonance periods, based on empirical measurements of support compliance, suggests that monkeys specifically employed branch pumping on relatively thin branches with protracted periods of oscillation. Finally, an additional four recordings show that both red colobus and black and white colobus monkeys (Colobus guereza) utilize tree swaying to cross large gaps, augmenting horizontal velocity at take-off. DISCUSSION: This deliberate branch manipulation to produce a mechanical effect for stronger propulsion is consistent with the framework of instrumental problem-solving. To our knowledge, this is the first study of wild primates which quantitatively shows how compliant branches can be used advantageously to augment locomotor performance.
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Árboles , Animales , Fenómenos Biomecánicos/fisiología , Masculino , Femenino , Árboles/fisiología , Locomoción/fisiología , Colobus/fisiologíaRESUMEN
The recent development of the Red Colobus Conservation Action Plan has spurred momentum to promote site-based conservation of red colobus while forging partnerships among researchers and building local capacity. Communities for Red Colobus (C4RC) is a community-centered conservation organization in The Gambia, West Africa, that aims to protect Temminck's red colobus (Piliocolobus badius temminckii) while advancing opportunities for local people. We highlight the inception and initial development of C4RC with its educational and ranger teams and describe how local and international collaborations have positively impacted the organization through training and mentoring programs. This conservation program has the potential to become sustainable with plans for continued ecological monitoring, reforestation efforts, use of alternative methods of cooking, and the expansion of ecotourism. We hope that the dissemination of project information through Gambian broadcast and social media channels and wider community outreach activities will improve perceptions and conservation of primates and inspire the development of other red colobus initiatives at suitable forest sites based on the C4RC model of community-based conservation.
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Colobinae , Virus de la Inmunodeficiencia de los Simios , Animales , Colobus , África OccidentalRESUMEN
OBJECTIVES: Although a bounding gait is practiced by a diversity of animals, the morphological characteristics, kinematics, and energetics associated with this locomotor form remain poorly understood. This study focuses on the locomotor anatomy of two species of African colobine monkeys (Piliocolobus badius, a leaper, and Colobus polykomos, a leaper-bounder) in an effort to assess if bounding should be considered a unique primate locomotor category or is better viewed as a behavior on a leaping continuum. MATERIALS AND METHODS: A total of 53 femora, 28 humeri, and 45 ossa coxae from the two species provide comparative morphological data. Free-body models of bounding and leaping are presented to characterize loading conditions. Species differences in morphometric traits are evaluated via parametric and nonparametric tests (i.e., analysis of variance, resampling). RESULTS: C. polykomos exhibits traits that align more closely with putative leaping specializations when compared to P. badius (e.g., large femoral head, long femur, low femoral neck angle), while also possessing certain traits that are not (e.g., long femoral neck and reduced relative femoral robusticity). Consequently, C. polykomos likely experiences absolutely greater joint forces at the hip and higher bending at the femoral neck both when it leaps and bounds, given equivalent accelerations in bounding and leaping. DISCUSSION: Bounding is best described as a form of low-acceleration leaping. If bounding has lower acceleration requirements relative to leaping, C. polykomos achieves locomotor competence with less energy, relatively smaller bending moments, and reduced joint forces.
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Colobus , Locomoción , Animales , Cercopithecidae/anatomía & histología , Marcha , Extremidad InferiorRESUMEN
Understanding the phylogenetic relationships among hominins and other hominoid species is critical to the study of human origins. However, phylogenetic inferences are dependent on both the character data and taxon sampling used. Previous studies of hominin phylogenetics have used Papio and Colobus as outgroups in their analyses; however, these extant monkeys possess many derived traits that may confound the polarities of morphological changes among living apes and hominins. Here, we consider Victoriapithecus and Ekembo as more suitable outgroups. Both Victoriapithecus and Ekembo are anatomically well known and are widely accepted as morphologically primitive stem cercopithecoid and hominoid taxa, respectively, making them more appropriate for inferring polarity for later-occurring hominoid- and hominin-focused analyses. Craniodental characters for both taxa were scored and then added to a previously published matrix of fossil hominin and extant hominoid taxa, replacing outgroups Papio and Colobus over a series of iterative analyses using both parsimony and Bayesian inference methods. Neither the addition nor replacement of outgroup taxa changed tree topology in any analysis. Importantly, however, bootstrap support values and posterior probabilities for nodes supporting their relationships generally increased compared to previous analyses. These increases were the highest at extant hominoid and basal hominin nodes, recovering the molecular ape phylogeny with considerably higher support and strengthening the inferred relationships among basal hominins. Interestingly, however, the inclusion of both extant and fossil outgroups reduced support for the crown hominid node. Our findings suggest that, in addition to improving character polarity estimation, including fossil outgroups generally strengthens confidence in relationships among extant hominoid and basal hominins.
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Hominidae , Humanos , Animales , Hominidae/anatomía & histología , Filogenia , Fósiles , Teorema de Bayes , Colobus , Papio , Evolución BiológicaRESUMEN
Many anthropogenic-driven changes, such as hunting, have clear and immediate negative impacts on wild primate populations, but others, like climate change, may take generations to become evident. Thus, informed conservation plans will require decades of population monitoring. Here, we expand the duration of monitoring of the diurnal primates at Ngogo in Kibale National Park, Uganda, from 32.9 to 47 years. Over the 3531 censuses that covered 15,340 km, we encountered 2767 primate groups. Correlation analyses using blocks of 25 census walks indicate that encounters with groups of black and white colobus, blue monkeys, and baboons neither increased nor decreased significantly over time, while encounters with groups of redtail monkeys and chimpanzees marginally increased. Encounters with mangabeys and L'Hoesti monkeys increased significantly, while red colobus encounters dramatically decreased. Detailed studies of specific groups at Ngogo document changes in abundances that were not always well represented in the censuses because these groups expanded into areas away from the transect, such as nearby regenerating forest. For example, the chimpanzee population increased steadily over the last 2 + decades but this increase is not revealed by our census data because the chimpanzees expanded, mainly to the west of the transect. This highlights that extrapolating population trends to large areas based on censuses at single locations should be done with extreme caution, as forests change over time and space, and primates adapt to these changes in several ways.
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Pan troglodytes , Parques Recreativos , Animales , Uganda , Dinámica Poblacional , Primates , Colobus , PapioRESUMEN
BACKGROUND: Conductive anaesthesia of the nerves around the head is one of the methods of intraoperative pain relief (under deep anaesthesia but before proceeding with the procedure). Performing this procedure on primates is especially challenging for the veterinarian, due to their cranial anatomy and topography, which has more in common with the human skull than with the skulls of other animals. Knowledge of key bony structures, including cranial foramina, is essential for effective anaesthesia of the cranial nerves. RESULTS: In this study, the differences in the topography of the cranial foramina in eight selected species of primates were examined: Angola colobus (Colobus angolensis), Celebes crested macaque (Macaca nigra), L'Hoest's monkey (Allochrocebus lhoesti), baboon (Papio cynocephalus), buff-bellied capuchin (Sapajus xanthosternos), black-and-white ruffed lemur (Varecia variegata), crowned lemur (Eulemur coronatus), and a ring-tailed lemur (Lemur catta) coming from the Wroclaw Zoological Garden (Poland). The cranial nerves running through the foramina have also been described and their anaesthesia techniques against bone points have been tested to relieve post-operative pain in the area of the head supplied by these nerves. CONCLUSION: The tests carried out show differences in the topography of the cranial foramina, and therefore also differences in the methods of injection, so the results obtained in this study may be useful in veterinary medicine, especially for practising veterinarians.
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Anestesia , Cebidae , Lemur , Lemuridae , Humanos , Animales , Cercopithecidae , Colobus , Osteología , Primates , Macaca , Cráneo , Nervios Craneales , Anestesia/veterinariaRESUMEN
This study provides ultrasonographic fetal growth charts for the Eastern black-and-white colobus monkey (Colobus guereza). Throughout three consecutive gestations (-162 to -2 days to parturition) in a single dam, we opportunistically obtained ultrasonographic measurements for the following parameters: biparietal diameter, head circumference, humerus length, femur length, tibia length, radius length, thoracic width, kidney length, and crown-rump length. Biparietal diameter was the most consistently measured parameter. First detection of fetuses occurred between 96 and 162 days before parturition. This report demonstrates that voluntary transabdominal ultrasound can be well-tolerated in the colobus monkey using operant conditioning. These findings may be useful to assess fetal development and predict parturition dates in the absence of a known conception date in this species.
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Animales de Zoológico , Colobus , Embarazo , Femenino , Animales , Feto , Parto , Ultrasonografía Prenatal/veterinaria , Edad GestacionalRESUMEN
This study investigates aspects of molar form in three African colobine species: Colobus polykomos, Colobus angolensis, and Piliocolobus badius. Our samples of C. polykomos and P. badius are from the Taï Forest, Ivory Coast; our sample of C. angolensis is from Diani, Kenya. To the extent that protective layers surrounding seeds are hard, we predicted that molar features related to hard-object feeding would be more pronounced in Colobus than they are Piliocolobus, as seed-eating generally occurs at higher frequencies in species of the former. We further predicted that among the colobines we studied, these features would be most pronounced in Taï Forest C. polykomos, which feeds on Pentaclethra macrophylla seeds encased within hard and tough seed pods. We compared overall enamel thickness, enamel thickness distribution, absolute crown strength, cusp tip geometry, and flare among molar samples. Sample sizes per species and molar type varied per comparison. We predicted differences in all variables except overall enamel thickness, which we expected would be invariant among colobines as a result of selection for thin enamel in these folivorous species. Of the variables we examined, only molar flare differed significantly between Colobus and Piliocolobus. Our findings suggest that molar flare, an ancient feature of cercopithecoid molars, was retained in Colobus but not in Piliocolobus, perhaps as a result of differences in the seed-eating proclivities of the two genera. Contrary to predictions, none of the aspects of molar form we investigated tracked current dietary differences in seed-eating between the two Colobus species. Finally, we explored the possibility that molar flare and absolute crown strength, when analyzed together, might afford greater differentiation among these colobine species. A multivariate t test of molar flare and absolute crown strength differentiated C. polykomos and P. badius, possibly reflecting known niche divergence between these two sympatric Taï Forest species.
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Colobinae , Colobus , Animales , Côte d'Ivoire , Dieta , Diente MolarRESUMEN
Across zoo's accredited by the Association of Zoos and Aquariums (AZA), species are typically managed as a single population to retain 90% of the founding members' gene diversity. Often, little is known about the specific geographic origins of the founders or how representative the ex situ population's genetic diversity is of the wild population. This study uses mitochondrial DNA (mtDNA) sequencing to investigate haplotype diversity and geographic female founder origin of the AZA-managed Angolan colobus (Colobus angolensis) monkey population. We obtained fecal samples from individuals closely related to founder animals at five zoos and found four haplotypes among 23 individuals. Analyzed together with wild C. angolensis haplotypes, we found two haplotypes identical to those found in Tanzanian populations: one haplotype, possessed by 13 individuals (descended from three founders), matched an East Usambara Mountains haplotype, while the other, possessed by seven individuals (from four founders), matched a haplotype found in both the South Pare Mountains and Rufiji River. Two haplotypes were not detected in wild populations but were closely related to haplotypes found in the Rufiji River (one individual descended from one founder) and Shimoni, Kenya (two individuals descended from one founder) populations, suggesting nearby origins. Thus, the AZA-managed population of Angolan colobus likely originated from several localities, but all have mtDNA lineages associated with the subspecies C. a. palliatus, a Vulnerable subspecies. Examining founders' mtDNA haplotypes may be a useful addition to the zoo population management toolkit to help improve breeding recommendations by identifying individuals with rare haplotypes and revealing likely kinship among founders.
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Animales de Zoológico , Colobus , Humanos , Femenino , Animales , Colobus/genética , Animales de Zoológico/genética , ADN Mitocondrial/genética , Haplotipos , Variación GenéticaRESUMEN
Almost one-quarter of primate species are reported to be involved in vehicle collisions. To mitigate these collisions, canopy bridges are used though their effectiveness is not broadly substantiated. We studied bridge impact on 23 years of vehicle collisions (2000-2022: N = 765) with colobus (Colobus angolensis palliatus), Sykes' (Cercopithecus mitis albogularis), and vervet (Chlorocebus pygerythrus hilgerti) monkeys in Diani, Kenya. Along a 9 km road, collisions did not decrease over the study duration, although bridges increased from 8 to 30. Using the kernel density estimation plus (KDE+) method, collisions appeared highly concentrated at some locations. These concentrations, called hotspots, represent hazardous road segments, though the hotspots for all three species overlapped for only 3% of the road length. We then inspected the collision hotspots over time, using the spatiotemporal extension of the KDE+ method. We compared hotspot presence in the 3 years before and after bridge installation to determine if bridges mitigated these hotspots. Hotspots disappeared for ~60% of bridges postinstallation, suggesting that bridges effectively reduce some collisions. However, of the bridges installed in locations that were not hotspots, 13% had hotspots emerge. Surprisingly, regardless of preinstallation hotspot occurrence, almost one-fifth of bridges had postinstallation hotspots. To understand the extent to which bridges mitigate collisions, other factors need consideration, including species attributes and crossing behavior, and road features and vehicle volume. We used the novel analytical method because it best suited our data set, given the challenges of determining the bridge impact zone and the low collision frequency.
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Colobus , Primates , Animales , Chlorocebus aethiops , Haplorrinos , Análisis Espacio-Temporal , Análisis Espacial , Accidentes de TránsitoRESUMEN
Rare behaviors are often missing from published papers, hampering phylogenetic analyses. Here, we report, for the first time, masturbation and same-sex sexual behavior (SSB) in both male and female black-and-white colobus monkeys. We recorded these behaviors during 32 months of observation (1573 h of focal animal sampling) on Colobus vellerosus collected at the Boabeng-Fiema Monkey Sanctuary in Ghana. Males were observed masturbating and involved in SSB more than females. Subadult males were the age-sex class that engaged in both of these behaviors most often and a third of all SSB observed in young males occurred when they were forming an all-male band (AMB), which are temporally transient social groups in this species. Our data support that masturbation in males may be a sexual outlet for individuals that do not have a current sexual partner, while in females it may function in mate attraction by advertising receptivity. SSB may occur as an evolutionary byproduct but given the temporal clustering of observed events in males prior to AMB formation, our data best support the hypothesis that these behaviors facilitate male-male bonding (i.e., act as social glue). Within AMB's, males engage in coalitionary behavior to take over social groups containing females and strong bonds are important for success and later access to females, which could have selected for SSB in C. vellerosus.
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Colobus , Conducta Social , Animales , Masculino , Femenino , Humanos , Filogenia , Conducta Sexual , GhanaRESUMEN
Analysis of glucocorticoid profiles serves as a valuable, multi-faceted tool for insight into the behavior and physiology of wild populations. Recently, the measurement of fecal glucocorticoid metabolites (FCMs) has exploded in popularity due to its compatibility with noninvasive techniques and remote environments A critical first step is to perform a biological validation to ensure that the assay accurately reflect changes in FCM levels. We use an enzyme immunoassay (EIA) to perform a biological validation on samples collected from two males and six females in a wild population of Colobus vellerosus in response to three naturally occurring potential stressors. We also describe the FCM response pattern in the week following parturition in three females and examine the influence of sex, reproductive state, and time of day on the concentrations of baseline samples collected daily from 13 adult individuals over a period of four months. We validated the assay: FCM levels increase in response to natural stressors with a two-day lag. In the two days surrounding parturition, FMC levels increased. Baseline concentrations were affected by collection time and female reproductive state, with lactating females having lower concentrations than pregnant or cycling females. Thus, we successfully carried out the first validation and characterization of FCMs in a wild African colobine. This will serve as an essential foundation for future studies of C. vellerosus and similar wild primates whose objective is to investigate the role glucocorticoids play in responses to social and ecological challenges.
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Colobus , Glucocorticoides , Animales , Embarazo , Masculino , Femenino , Glucocorticoides/metabolismo , Colobus/metabolismo , Lactancia , Reproducción , Parto , HecesRESUMEN
In tropical forests, anthropogenic activities are major drivers of the destruction and degradation of natural habitats, causing severe biodiversity loss. African colobine monkeys (Colobinae) are mainly folivore and strictly arboreal primates that require large forests to subsist, being among the most vulnerable of all nonhuman primates. The Western red colobus Piliocolobus badius and the King colobus Colobus polykomos inhabit highly fragmented West African forests, including the Cantanhez Forests National Park (CFNP) in Guinea-Bissau. Both species are also found in the largest and best-preserved West African forest-the Taï National Park (TNP) in Ivory Coast. Colobine monkeys are hunted for bushmeat in both protected areas, but these exhibit contrasting levels of forest fragmentation, thus offering an excellent opportunity to investigate the importance of well-preserved forests for the maintenance of evolutionary potential in these arboreal primates. We estimated genetic diversity, population structure, and demographic history by using microsatellite loci and mitochondrial DNA. We then compared the genetic patterns of the colobines from TNP with the ones previously obtained for CFNP and found contrasting genetic patterns. Contrary to the colobines from CFNP that showed very low genetic diversity and a strong population decline, the populations in TNP still maintain high levels of genetic diversity and we found no clear signal of population decrease in Western red colobus and a limited decrease in King colobus. These results suggest larger and historically more stable populations in TNP compared to CFNP. We cannot exclude the possibility that the demographic effects resulting from the recent increase of bushmeat hunting are not yet detectable in TNP using genetic data. Nevertheless, the fact that the TNP colobus populations are highly genetically diverse and maintain large effective population sizes suggests that well-preserved forests are crucial for the maintenance of populations, species, and probably for the evolutionary potential in colobines.
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Colobinae , Colobus , Animales , Colobus/genética , Colobinae/genética , Bosques , Evolución Biológica , ÁrbolesRESUMEN
Habitat destruction and over-hunting are increasingly threatening the arboreal primates of Central Africa. To establish effective conservation strategies, accurate assessments of primate density, abundance, and spatial distribution are required. To date, the method of choice for primate density estimation is line transect distance sampling. However, primates fleeing human observers violate methodological assumptions, biasing the accuracy of resulting estimates. In this study, we used line transect distance sampling to study five primate species along 378 km of transects in Salonga National Park, Democratic Republic of the Congo. We tested the effect of different levels of survey-inherent disturbance (i.e., cutting) on the number of observed (i) primate groups, and (ii) individuals within groups, by counting groups at three different time lags after disturbance of the transect, (i) a minimum of 3 h, (ii) 24 h, (iii) a minimum of 3 days. We found that survey-inherent disturbance led to underestimated densities, affecting both the number of encountered groups and of observed individuals. However, the response varied between species due to species-specific ecological and behavioral features. Piliocolobus tholloni and Colobus angolenis resumed an unaltered behavior only 24 h after disturbance, while Lophocebus aterrimus, Cercopithecus ascanius, and Cercopithecus wolfi required a minimum of 10 days. To minimize bias in density estimates, future surveys using line transect distance sampling should be designed considering survey-inherent disturbance. We recommend evaluating the factors driving primate response, including habitat type, niche occupation, and hunting pressure, peculiar to the survey-specific area and primate community under study.
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Colobinae , Ecología , Ecosistema , Animales , Colobus , Densidad de Población , Árboles , Ecología/métodosRESUMEN
A 14-year-old female black and white colobus monkey (Colobus guereza) presented in labor with fetal arms visible protruding from the vulva. Manual manipulation for assisted delivery of the fetus was unsuccessful. Radiographs identified a large fetal skull and hysterotomy was required with ovariohysterectomy elected to follow. The fetus was confirmed to be deceased during hysterotomy, but the dam recovered from the procedure uneventfully. The detailed description of the anesthesia and surgical procedure in this case may aid other clinicians when presented with similar dystocia cases in this species.
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Colobus , Distocia , Femenino , Animales , Distocia/cirugía , Distocia/veterinariaRESUMEN
BACKGROUND: Modern human brains and skull shapes differ from other hominids. Brain growth disorders as micro- (ASPM, MCPH1) and macrocephaly (NFIX, GLI3) have been highlighted as relevant for the evolution in humans due to the impact in early brain development. Genes associated with macrocephaly have been reported to cause this change, for example NSD1 which causes Sotos syndrome. RESULTS: In this study we performed a systematic literature review, located the reported variants associated to Sotos syndrome along the gene domains, compared the sequences with close primates, calculated their similarity, Ka/Ks ratios, nucleotide diversity and selection, and analyzed the sequence and structural conservation with distant primates. We aimed to understand if NSD1 in humans differs from other primates since the evolution of NSD1 has not been analyzed in primates, nor if the localization of the mutations is limited to humans. Our study found that most variations causing Sotos syndrome are in exon 19, 22 and 10. In the primate comparison we did not detect Ka/Ks ratios > 1, but a high nucleotide diversity with non-synonymous variations in exons 10, 5, 9, 11 and 23, and sites under episodic selection in exon 5 and 23, and human, macaque/colobus/tarsier/galago and tarsier/lemur/colobus. Most of the domains are conserved in distant primates with a particular progressive development from a simple PWWP1 in O. garnetti to a complex structure in Human. CONCLUSION: NSD1 is a chromatin modifier that suggests that the selection could influence brain development during modern human evolution and is not present in other primates; however, nowadays the nucleotide diversity is associated with Sotos syndrome.
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Hominidae , Megalencefalia , Síndrome de Sotos , Tarsiidae , Humanos , Animales , Síndrome de Sotos/genética , Histona Metiltransferasas/genética , N-Metiltransferasa de Histona-Lisina/genética , Tarsiidae/genética , Colobus/genética , Proteínas Nucleares/genética , Mutación , Exones/genética , Hominidae/genética , Megalencefalia/genética , Nucleótidos , Proteínas del Citoesqueleto/genética , Proteínas de Ciclo Celular/genéticaRESUMEN
Habitat loss and fragmentation affect the diversity and distribution of primates in a human-modified landscape. Ethiopia has a high diversity of primates, but increasing human pressure has negatively impacted their distribution and abundance across the country, primarily due to deforestation. To date, the diversity and distribution of primate species are poorly known in northwestern Ethiopia. From October 2020 until September 2021, we assessed the diversity and distribution of primate species in 26 forest patches in the Awi Zone, Northwestern Ethiopia using line transect surveys, and we examined the potential conservation threats to the survival of these taxa. Across transects, we encountered 459 groups of four primate taxa: olive baboons (Papio anubis), grivet monkeys (Chlorocebus aethiops), Boutourlini's blue monkeys (Cercopithecus mitis boutourlinii), and black-and-white colobus monkeys (Colobus guereza spp. guereza). The latter two are endemic to Ethiopia. We observed black-and-white colobus monkeys in all surveyed forest patches, while we observed Boutourlini's blue monkeys in 18 patches. Black-and-white colobus monkeys were the most frequently observed (n = 325 sighting; relative encounter frequency = 70.8%), while grivet monkeys (Chlorocebus aethiops) were the least (n = 34 sighting; relative encounter frequency = 7.4%) in the region. Similarly, the relative encounter frequency of olive baboons was 9.2% (n = 42 sighting). The overall mean group size for each species was: Boutourlini's blue monkeys (26.1 individuals), black-and-white colobus monkeys (8.8 individuals), grivet monkeys (34.1 individuals), and olive baboons (41.4 individuals). We identified agricultural expansions, exotic tree plantations, deforestations, firewood collections, livestock grazing, and killings over their crop-feeding behaviors as the main threats to primates and their habitats in the region. This study provides crucial information on an area likely to support primate species that we know very little about. Assigning protected connecting forest patches should be an urgent priority for the conservation of the primates in this region.