The primate cerebral cortex is characterized by regional variation in the structure of pyramidal neurons, with more complex dendritic arbors and greater spine density observed in prefrontal compared with sensory and motor cortices. Although there are several investigations in humans and other primates, virtually nothing is known about regional variation in the morphology of pyramidal neurons in the cerebral cortex of great apes, humans' closest living relatives. The current study uses the rapid Golgi stain to quantify the dendritic structure of layer III pyramidal neurons in 4 areas of the chimpanzee cerebral cortex: Primary somatosensory (area 3b), primary motor (area 4), prestriate visual (area 18), and prefrontal (area 10) cortex. Consistent with previous studies in humans and macaque monkeys, pyramidal neurons in the prefrontal cortex of chimpanzees exhibit greater dendritic complexity than those in other cortical regions, suggesting that prefrontal cortical evolution in primates is characterized by increased potential for integrative connectivity. Compared with chimpanzees, the pyramidal neurons of humans had significantly longer and more branched dendritic arbors in all cortical regions.

Human beings are thought to be unique amongst the primates in their capacity to produce rapid changes in the shape of their vocal tracts during speech production. Acoustically, vocal tracts act as resonance chambers, whose geometry determines the position and bandwidth of the formants. Formants provide the acoustic basis for vowels, which enable speakers to refer to external events and to produce other kinds of meaningful communication. Formantbased referential communication is also present in non-human primates, most prominently in Diana monkey alarm calls. Previous work has suggested that the acoustic structure of these calls is the product of a non-uniform vocal tract capable of some degree of articulation. In this study we test this hypothesis by providing morphological measurements of the vocal tract of three adult Diana monkeys, using both radiography and dissection. We use these data to generate a vocal tract computational model capable of simulating the formant structures produced by wild individuals. The model performed best when it combined a non-uniform vocal tract consisting of three different tubes with a number of articulatory manoeuvres. We discuss the implications of these findings for evolutionary theories of human and nonhuman vocal production.

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The threat of disease transmission from domestic animals to wildlife has become recognized as an increasing concern within the wildlife community in recent years. Domestic dogs pose a significant risk as reservoirs for infectious diseases, especially for wild canids. As part of a multifaceted ecologic study of maned wolves and other canids in the large, remote Noël Kempff Mercado National Park (NKMNP) in northeastern Bolivia, 40 domestic dogs in two villages and at two smaller settlements bordering the national park were sampled for exposure to canine diseases. High levels of exposure were found to canine distemper virus and canine parvovirus, both of which are known to cause mortality in maned wolves and other carnivores. Moderate to high levels of exposure were found to rabies virus, Ehrlichia canis, and Toxoplasma gondii, as well as significant levels of infection with Dirofilaria immitis. This study reports evidence of exposure to several diseases in the domestic dogs bordering the park. Contact between wild carnivores and dogs has been documented in the sampled villages, therefore dogs likely pose a substantial risk to the carnivores within and near NKMNP. Further measures should be undertaken to decrease the risk of spillover infection from domestic animals into the wild species of this region.

Frog virus 3 (FV3) and FV3-like viruses are members of the genus Ranavirus (family Iridoviridae) and are becoming recognized as significant pathogens of eastern box turtles (Terrapene carolina carolina) in North America. In July 2011, 5 turtles from a group of 27 in Maryland, USA, presented dead or lethargic with what was later diagnosed as fibrinonecrotic stomatitis and cloacitis. The presence of FV3-like virus and herpesvirus was detected by polymerase chain reaction (PCR) in the tested index cases. The remaining 22 animals were isolated, segregated by severity of clinical signs, and treated with nutritional support, fluid therapy, ambient temperature management, antibiotics, and antiviral therapy. Oral swabs were tested serially for FV3-like virus by quantitative real-time PCR (qPCR) and tested at day 0 for herpesvirus and Mycoplasma sp. by conventional PCR. With oral swabs, 77% of the 22 turtles were FV3-like virus positive; however, qPCR on tissues taken during necropsy revealed the true prevalence was 86%. FV3-like virus prevalence and the median number of viral copies being shed significantly declined during the outbreak. The prevalence of herpesvirus and Mycoplasma sp. by PCR of oral swabs at day 0 was 55% and 68%, respectively. The 58% survival rate was higher than previously reported in captive eastern box turtles for a ranavirus epizootic. All surviving turtles brumated normally and emerged the following year with no clinical signs during subsequent monitoring. The immediate initiation of treatment and intensive supportive care were considered the most important contributing factors to the successful outcome in this outbreak.