Vocal activity of lesser galagos (Galago spp.) at zoos.

Almost nothing is known about the natural vocal behavior of lesser galagos living in zoos. This is perhaps because they are usually kept in nocturnal exhibits separated from the visitors by a transparent and acoustically insulating glass barrier. The aim of the present study was therefore to fill this gap in knowledge of the vocal behavior of lesser galagos from zoos. This knowledge might be beneficial because the vocalizations of these small primates can be used for species determination. We performed a 10-day-long acoustic monitoring of vocal activity in each of seven various groups of Galago senegalensis and G. moholi living at four zoos. We quantitatively evaluated the occurrence of four loud vocalization types present in both species, including the most species-specific advertisement call. We found that qualitative as well as quantitative differences exist in the vocal behavior of the studied groups. We confirmed that the observed vocalization types can be collected from lesser galagos living at zoos, and the success can be increased by selecting larger and more diverse groups. We found two distinct patterns of diel vocal activity in the most vocally active groups. G. senegalensis groups were most vocally active at the beginning and at the end of their activity period, whereas one G. moholi group showed an opposite pattern. The latter is surprising, as it is generally accepted that lesser galagos emit advertisement calls especially at dawn and dusk, i.e., at the beginning and at the end of their diel activity.

Characterizing cryptic species: A morphometric analysis of craniodental characters in the dwarf galago genus Galagoides.

OBJECTIVES: The true dwarf galagos of the genus Galagoides, G. demidoff and G. thomasi, are difficult to distinguish morphologically at a specific or subspecific level, and most taxonomic designations are based primarily on geographic localities. We used morphometrics to investigate the morphological diversity of the genus. MATERIALS AND METHODS: We conducted statistical analyses of 12 linear measurements on 290 Galagoides skulls housed in museums worldwide, and assembled body weights for 71 wild caught specimens. We examined sexual dimorphism and specific and subspecific distinctiveness using MANOVA, ANOVA, principle components analysis and canonical variate analysis. RESULTS: We distinguished skulls identified as Galagoides demidoff and G. thomasi with ∼70% reliability, and demonstrated consistently different patterns of static allometry in craniodental variables. Variables supporting specific distinction included M1 width, palate width at P2 , palate (snout) length, length of premaxillary tube, width across mastoids, and total skull length. The type specimens of G. orinus and G. rondoensis were significantly different from G. demidoff and G. thomasi, but grouped with them in a CVA including G. zanzibaricus and G. granti, although molecular studies indicate that their true affiliation is with the latter species. Subspecies within G. demidoff could not be distinguished using craniodental morphometrics. DISCUSSION: Galagoides demidoff and G. thomasi can be distinguished relatively reliably, and are broadly sympatric across western and central Africa. Neither species showed evidence of sexual dimorphism in craniodental size or shape. Size variation has a greater influence on skull morphology in G. demidoff than it has on G. thomasi. Am J Phys Anthropol 158:288-299, 2015. © 2015 Wiley Periodicals, Inc.

Northern lesser galagos (Galago senegalensis) increase the production of loud calls before and at dawn.

Functional explanations for loud calling in nocturnal primates include territorial or sexual advertisement, maintenance of cohesiveness, and group coordination. It is generally accepted that loud calls of lesser galagos (genus Galago) are used for territorial advertisement and long-distance spacing. Field studies suggest that they are uttered at dusk and dawn, when the animals leave and reunite at their sleeping sites. However, empirical validation of these inferences is lacking. We conducted 16-night-long acoustic monitoring of a northern lesser galago (G. senegalensis) population in Senegal and quantified the occurrence of loud calls throughout the night. We hypothesized that significantly more of these calls would be emitted at dusk and dawn if they were used for territorial advertisement and long-distance spacing. This hypothesis was only partially supported, as we found an asymmetrical distribution of loud calls, which significantly increased only before and at dawn. The finding that the relatively early increase in vocal activity was not directly related to approaching and entering sleeping sites suggests that the northern lesser galagos' loud calls differ in function from reassembly calls described for other species of nocturnal primates. Furthermore, the early onset cannot be explained by changes in the intensity of sunlight, moonlight or starlight, which suggests that a different stimulus, most likely internal, elicits early-morning calling behavior in northern lesser galagos.

Remarkable ancient divergences amongst neglected lorisiform primates.

Lorisiform primates (Primates: Strepsirrhini: Lorisiformes) represent almost 10% of the living primate species and are widely distributed in sub-Saharan Africa and South/South-East Asia; however, their taxonomy, evolutionary history, and biogeography are still poorly understood. In this study we report the largest molecular phylogeny in terms of the number of represented taxa. We sequenced the complete mitochondrial cytochrome b gene for 86 lorisiform specimens, including ∼80% of all the species currently recognized. Our results support the monophyly of the Galagidae, but a common ancestry of the Lorisinae and Perodicticinae (family Lorisidae) was not recovered. These three lineages have early origins, with the Galagidae and the Lorisinae diverging in the Oligocene at about 30 Mya and the Perodicticinae emerging in the early Miocene. Our mitochondrial phylogeny agrees with recent studies based on nuclear data, and supports Euoticus as the oldest galagid lineage and the polyphyletic status of Galagoides. Moreover, we have elucidated phylogenetic relationships for several species never included before in a molecular phylogeny. The results obtained in this study suggest that lorisiform diversity remains substantially underestimated and that previously unnoticed cryptic diversity might be present within many lineages, thus urgently requiring a comprehensive taxonomic revision of this primate group.