Long-term dynamics of wild primate populations across forests with contrasting protection in Tanzania

Anthropogenic activities driving tropical forests' loss imperil global biodiversity and provision of ecosystem services. In this context, systematic monitoring programs evaluating wildlife trends are essential. Non-human primates are relevant conservation targets since they represent vital components of tropical forests by serving as pollinators and seed dispersers. Here, we present primate group counts data collected over 19 years in a primate hotspot in Tanzania. We analyzed data with a hierarchical dynamic model accounting for imperfect detection that estimates local group abundance and temporal rates of change, to assess whether habitat protection explained trends of the arboreal and diurnal Peters' Angola colobus (Colobus angolensis palliatus), Udzungwa red colobus (Piliocolobus gordonorum), and Tanzania Sykes' monkey (Cercopithecus mitis subsp. moloneyi). We targeted populations occurring in two forest blocks with contrasting protection regimes, with one block impacted by targeted poaching of the two Colobus species. We found that these latter species were much less abundant in the more human impacted forest, underwent a rapid decline, and subsequently remained at low abundance and without signs of recovery once this forest was granted greater protection. Instead, Sykes' abundance did not differ between forests, and improved protection was associated with a slight increase in abundance. Age class composition for social groups of both Colobus species differed between forests, indicating altered births and survivorship rates in the impacted forest. Results suggest that targeted hunting can prevent recovery for several years and even after increased habitat protection. Our approach appears valuable to monitor population dynamics over the long term, highlighting species-specific variations in both vulnerability to anthropogenic disturbance and recovery patterns in primate populations.     

Abundance, diversity, and patterns of distribution of primates on the Tapiche River in Amazonian Peru

This work presents data on the relative diversity, abundance, and distribution patterns of primates in a 20 km2 area of the Tapiche River in the Peruvian Amazon. Population data were collected while the study area was both inundated and dry (March to September 1997) using conventional line-transect census techniques. Survey results reflected the presence of 11 primate species, but population parameters on only eight of the species will be presented, including saddleback tamarins (Saguinus fuscicollis), Bolivian squirrel monkeys (Saimiri boliviensis), brown capuchins (Cebus apella), white-fronted capuchins (Cebus albifrons), monk sakis (Pithecia monachus), red titi monkeys (Callicebus cupreus), red uakaris (Cacajao calvus), and red howler monkeys (Alouatta seniculus). Woolly monkeys (Lagothrix lagotricha), night monkeys (Aotus nancymaae), and pygmy marmosets (Callithrix pygmaea) were also seen in the area. The data for the smaller-bodied primates is similar to that reported almost 18 years earlier, but the data for the larger-bodied primates reflect a loss in the number of animals present in the area. Pressure from hunters and the timber industry may account for declining numbers of large-bodied primates, while it appears that natural features peculiar to the conservation area contribute to the patchy pattern of distribution.     

The Fayum primate forest: Did it exist?

The primates have the reputation of being essentially arboreal, forest-adapted animals. Yet there are many genera and species that inhabit an extremely wide array of non-forest habitats. Nevertheless, palaeoprimatologists often tend to depict fossil primate habitats as being more arboreal and more forest-like than is justified by the facts. It is worthwhile, therefore, to reconsider some current interpretations. In this paper, evidence of the Fayum Oligocene primate deposits are reviewed and discussed. The following conclusions emerge:(1) The large number of primate species indicates that the Fayum ecosystem was an optimum or near-optimum habitat for primates. (2) The lithological characteristics point to a sahélien type of climate. (3) The calcified and silicified root systems, having diameters up to 4 cm, suggest a sahélien type of shrub, bushland and/or small-tree vegetation. (4) The large fossilized logs cannot have grown on the spot and apparently represent driftwood from a more humid climatic belt in the south, as is indicated by damage resulting from fluvial transportation and by palaeobotanical data. (5) There may have been some minor patches or strips of medium-height forests and/or wood-lands in the Fayum delta, but there is no evidence of these.Thus the tall forest in which the earliest known African primates are currently supposed to have lived probably never existed. Grounds for this conclusion were presented by Unger 121 years ago, by Beadnell 75 years ago and by Kräusel 41 years ago, but sank into oblivion. The classic image of the primates as arboreal specialists seems to have interfered with seeing the facts. However, more extensive verification of the evidence by means of palaeobotanical research is still required. The fossil material to do so is readily available.     

Spontaneous meningoencephalitis by Staphylococcus aureus in an infant golden‐headed lion tamarin (Leontopithecus chrysomelas)

Non‐human primates are susceptible to many bacteria, some of which bear zoonotic potential. We report the pathologic features of spontaneous fulminating meningoencephalitis by Staphylococcus aureus in a captive infant golden‐headed lion tamarin (Leontopithecus chrysomelas) from Brazil.     

Substrate Size and Primate Forelimb Mechanics: Implications for Understanding the Evolution of Primate Locomotion

International Journal of Primatology - Did the anatomical and locomotor specializations of primates evolve in response to requirements of locomotion and foraging on thin branches? Laboratory...     

Case study: Scoliosis in a Bonobo (Pan paniscus)

Differential diagnosis of observed morphological features on an adult male bonobo skeleton was consistent with idiopathic scoliosis. Directional asymmetry was an order of magnitude higher compared with asymptomatic skeletons. This possible case of idiopathic scoliosis contributes to data that suggest a weaker tie between bipedalism and scoliosis than previously hypothesized.     

Preliminary observations on squirrel monkey (Saimiri oerstedi) vocalizations in Costa Rica

This study was an initial attempt to analyze quantitatively vocalizations from the Central American squirrel monkey, Saimiri oerstedi. Vocalizations were recorded in the wild at P. N. Corcovado (S. o. oerstedi). and at P. N. Manuel Antonio (S. o. citrinellus). Additional recordings were made from captive individuals of both subspecies. The acoustic structure of analyzed vocalizations resembled most closely the vocal repertoire of South American Saimiri with the “gothic arch” phenotype, in agreement with the prominent gothic arch facial pattern of S. oerstedi. New structural subtypes of the twitter (“dog-tooth twitter”) and the chuck (“bent-mast chuck”) not previously found in an extensive library of South American Saimiri sound spectrograms were documented. Calls used by older infants when socially separated and when approaching an adult male were essentially identical (sharing typical “isolation peep” structural features) but had significantly different duration and peak frequency. Analysis of recordings from an escaped captive female calling outside her compound over a 3-day period indicated the presence of numerous structural intermediates between typical chuck, twitter, and peep calls.     

Primates as pets in Mexico City: an assessment of the species involved, source of origin, and general aspects of treatment

The large human populations in cities are an important source of demand for wildlife pets, including primates, and not much is known about the primate species involved in terms of their general origin, the length of time they are kept as pets, and some of the maintenance problems encountered with their use as pets. We report the results of a survey conducted in Mexico City among primate pet owners, which was aimed at providing some of the above information. We used an ethnographic approach, and pet owners were treated as informants to gain their trust so that we could enter their homes and learn about the life of their primate pets. We surveyed 179 owners of primate pets, which included 12 primate species. Of these, three were native species (Ateles geoffroyi, Alouatta pigra, and A. palliata). The rest were other neotropical primate species not native to Mexico, and some paleotropical species. Spider monkeys and two species of howler monkeys native to Mexico accounted for 67% and 15%, respectively, of the primate cases investigated. The most expensive primate pets were those imported from abroad, while the least expensive were the Mexican species. About 45% of the native primate pets were obtained by their owners in a large market in Mexico City, and the rest were obtained in southern Mexico. Although they can provide companionship for children and adults, primate pets are subject to a number of hazards, some of which put their lives at risk. The demand by city dwellers for primate pets, along with habitat destruction and fragmentation, exerts a significant pressure on wild populations in southern Mexico.     

LRP5 sequence and polymorphisms in the baboon

Background  LRP5 is known to have an important relationship with bone density and a variety of other biological processes. Mapping to human chromosome 11q13.2, LRP5 shows considerable evolutionary conservation. Orthologs of this gene exist in many species, although comparison of human LRP5 with other non-human primates has not been performed until now.
Methods  We reported the complementary DNA (cDNA) sequence and deduced amino acid sequence for baboon LRP5 , and compared the baboon and human sequences. cDNA sequences for 21 baboons were examined to identify single-nucleotide polymorphisms (SNPs).
Results  Sequences of coding regions in human and baboon LRP5 showed 97– 99% homology. Twenty-five SNPs were identified in the coding region of baboon LRP5 .
Conclusion  The observed degree of coding sequence homology in LRP5 led us to expect that the baboon may serve as a useful model for future research into the role(s) of this gene in primate metabolic diseases.     

Naturally occurring fatal herpes simplex virus 1 infection in a family of white-faced saki monkeys (Pithecia pithecia pithecia)

A family of three white-faced saki monkeys (Pithecia pithecia pithecia) died 48-96 hours after the onset of anorexia, nasal discharge, pyrexia and oral ulceration. One animal also had clonic seizures. Lesions found post-mortem consisted of oral and esophageal ulcers, hepatic and intestinal necrosis, meningoencephalitis and sporadic neuronal necrosis. Intranuclear inclusion bodies and syncytial cells were present in oral lesions and affected areas of liver. Herpes simplex virus 1 (HSV-1) was identified as the etiology of disease by virus isolation, polymerase chain reaction, or in situ hybridization in all three animals. Immunohistochemistry for detection of apoptotic DNA and activated caspase-3 showed significant levels of apoptosis in oral and liver lesions and occasional apoptotic neurons in the brain. These findings demonstrate the vulnerability of white-faced saki monkeys to HSV-1 and provide initial insight into the pathogenesis of fatal HSV-1-induced disease, indicating that apoptosis plays a significant role in cell death.     

Organ and gestational age effects of maternal nutrient restriction on global methylation in fetal baboons

Background  A sub-optimal intrauterine environment alters the trajectory of fetal development with profound effects on life-time health. Altered methylation, a proposed epigenetic mechanism responsible for these changes, has been studied in non-primate species but not nonhuman primates. We tested the hypotheses that global methylation in fetal baboon demonstrates organ specificity, gestational age specificity, and changes with maternal nutritional status.
Methods  We measured global DNA methylation in fetuses of control fed (CTR) and nutrient restricted mothers fed 70% of controls (MNR) for brain, kidney, liver and heart at 0.5 and 0.9 gestation (G).
Results  We observed organ and gestation specific changes that were modified by maternal diet. Methylation in CTR fetuses was highest in frontal cortex and lowest in liver. MNR decreased methylation in 0.5G kidney and increased methylation in 0.9G kidney and frontal cortex.
Conclusion  These results demonstrate a potential epigenetic mechanism whereby reduced maternal nutrition has long-term programming effects on fetal organ development.     

What Do Primates Hear? A Meta-analysis of All Known Nonhuman Primate Behavioral Audiograms

Research on the hearing abilities of nonhuman primates dates back >70 yr and there are audiograms —graphs showing hearing sensitivity over a range of frequencies— for 29 different species including representatives from almost every major group. However, the methods used to obtain the audiograms have been nearly as varied as the number of species tested. I sought to determine the degree to which one can directly compare the audiograms by examining several factors that could have a significant impact on the results: the behavioral conditioning procedure employed to train and test the subjects, the type of transducer used to deliver the test tones, the procedure used to calibrate the amplitude of the test tones, the acoustic enclosure used to minimize ambient noise, and the method used to determine the final threshold values. Audiograms produced using speakers cannot be compared directly with those produced using headphones, and in some cases the calibration procedure and testing chamber may also limit the potential for interspecific comparisons. Based on the findings, I provide 2 lists of optimal primate audiograms: 1 for speaker-derived audiograms and the other for headphone-derived audiograms. I measured a set of audiometric variables on each of the optimal audiograms, and phylogenetic comparisons of the data show that superfamilies of primates display unique patterns of hearing sensitivity, particularly at frequencies in the lower range. Lastly, I discuss the implications for behavioralists investigating primate vocalizations in the field.     

Built to last: The structure,function, and evolution of primate dental enamel

The teeth of every primate, living and extinct, are covered by a hard, durable layer of enamel. This is not unique: Almost all mammals have enamel-covered teeth. In addition, all of the variations in enamel structure that occur in primates are also found in other groups of mammals. Nevertheless, the very complexity of enamel and the variation we see in it on the teeth of living and fossil primates raise questions about its evolutionary significance. Is the complex structure of primate enamel adaptive? What, if anything, does enamel structure tell us about primate phylogeny? To answer these questions, we need to look more closely at the characteristics of prismatic enamel in primates and at the distribution of those characteristics, both in relation to our knowledge of primate dental function and feeding ecology and from a phylogenetic perspective.     

Understanding primate‐human interaction: Socioeconomic correlates of local awareness and attitude toward the endangered golden langur Trachypithecus geei (Khajuria, 1956) in Bhutan

Despite the golden langur's (Trachypithecus geei) endangered and totally protected status, local awareness and attitude toward this species is poorly understood. We investigated local awareness and attitude in Bhutan by interviewing 1,143 households in the districts of Dagana, Sarpang, Trongsa, Tsirang, and Zhemgang, and analyzing data through a conditional inference tree analysis. Most respondents were not aware of the golden langur's nationally protected (53%; n = 604) and globally endangered status (64%; n = 730), but their location of residence (inside/outside a protected area; p < .001) and education level (p < .001) significantly influenced awareness. The majority of respondents (87%; n = 999) liked the golden langur but the attitude was significantly influenced primarily by whether or not they experienced crop damage by golden langurs (p < .001), and subsequently by location of residence (p < .001), local belief (p < .01), gender (p < .05), and personal encounter with a golden langur (p < .001). Socioeconomic variables like age, education level, and annual income did not influence attitude. We recommend environmental education and awareness campaigns outside protected areas, and intensifying existing programs inside protected areas to forge harmonious human‐golden langur coexistence.     

Congenital bronchiolo-alveolar airway malformation in a cynomolgus macaque (Macaca fascicularis)

Pulmonary congenital anomalies in animals are rare. Previously reported malformations include accessory lung formation, pulmonary hypoplasia, pulmonary agenesis, and various forms of hamartoma. Congenital bronchiolo-alveolar airway malformation, a new entity, is described in a 1-day-old male cynomolgus macaque. This neonate experienced breathing difficulties shortly after birth and died while therapy was being administered. Grossly, the right lung was markedly increased in size, firm, and pink. Histopathologically, sections of right lung showed irregular bronchiole-like and alveolus-like structures. There was marked widening of alveolar septae by loosely arranged mesenchymal cells and many centrally located capillaries. Alveoli were lined by cuboidal epithelial cells. There were scattered islands of immature cartilage. A grossly enlarged lung containing bronchiole-like and alveolus-like structures, immature cartilage islands, and many capillaries within alveolar septae on histopathologic examination, is inconsistent with previously described congenital pulmonary anomalies in animals and humans.