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Overdorff, D. J., Erhart, E. M., & Mutschler, T. (2005). Does female dominance facilitate feeding priority in black-and-white ruffed lemurs (Varecia variegata) in southeastern Madagascar? Am. J. Primatol., 66(1), 7–22.
Abstract: Although many Malagasy lemurs are thought to be female dominant and to have female feeding priority, to date the relationship between these behaviors has been rigorously established only in Lemur catta, and other ways that females might achieve feeding priority have not been examined closely. Erhart and Overdorff [International Journal of Primatology 20:927-940, 1999] suggested that one way female primates achieve feeding priority is to initiate and lead groups to food, thereby gaining access to the food first and positively influencing their food intake compared to other group members. Here we describe female dominance patterns and potential measures of feeding priority in two groups of black-and-white ruffed lemurs (Varecia variegata) that were observed over a 15-month period in southeastern Madagascar. We predicted that the females would 1) be consistently dominant to males, 2) lead groups to food sources more often than males, and 3) have higher feeding rates compared to males when they arrived at food sources first. The results were dissimilar between the study groups. During the study, the oldest adult female in group 1 died. There was no evidence for female dominance in this group, and the remaining (likely natal) female did not lead the group more often, nor did she have a higher food intake than males. Group 1 dispersed shortly after the time frame reported here. In contrast, the resident female in group 2 was dominant to group males (based on agonistic interactions), led the group to food sources more often, and experienced a higher food intake when she arrived first at a food source. How these patterns vary over time and are influenced by the number of females in groups, group stability, food quality, and reproductive condition will be examined in future analyses.
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Palagi, E., Antonacci, D., & Norscia, I. (2008). Peacemaking on treetops: first evidence of reconciliation from a wild prosimian (Propithecus verreauxi). Anim. Behav., 76(3), 737–747.
Abstract: Reconciliation is defined as the first postconflict affinitive contact between former opponents. While reconciliation in anthropoid primates has been widely investigated, few studies have focused on postconflict mechanisms in prosimians, and only in captivity. Unlike anthropoids, Malagasy prosimians show female dominance, lack of sexual dimorphism and seasonal breeding. However, they share features with anthropoids such as cohesive societies, female philopatry and individual recognition. Comparing social prosimians with anthropoids is crucial for understanding the evolution of reconciliation dynamics. Here we present the first study on reconciliation in a wild prosimian. We focused on the Propithecus verreauxi (sifaka) of the Berenty forest (southern Madagascar). We examined postconflict behaviour in the light of theoretical expectations based on potential costs and benefits of the individuals involved. Our results indicate that P. verreauxi can evaluate possible risks and benefits of engaging in postconflict reunions. Victims were most likely to interact affinitively with the aggressor after low-intensity aggression. Moreover, only the conflicts occurring outside the feeding context were reconciled. Such results are consonant with the fact that, in P. verreauxi, social dominance is translated more into feeding priority than into a framework of despotic relationships. In agreement with the valuable relationship hypothesis, P. verreauxi were more likely to reconcile with valuable partners: reconciliation preferentially occurred between subordinates and top-ranking individuals, and between animals sharing good relationships (high levels of affinitive behaviours). Over the short term, reconciliation in P. verreauxi seems to have an important role in reducing the probability of further attacks by the aggressor.
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Sebastiani, F., Meiswinkel, R., Gomulski, L. M., Guglielmino, C. R., Mellor, P. S., Malacrida, A. R., et al. (2001). Molecular differentiation of the Old World Culicoides imicola species complex (Diptera, Ceratopogonidae), inferred using random amplified polymorphic DNA markers. Mol Ecol, 10(7), 1773–1786.
Abstract: Samples of seven of the 10 morphological species of midges of the Culicoides imicola complex were considered. The importance of this species complex is connected to its vectorial capacity for African horse sickness virus (AHSV) and bluetongue virus (BTV). Consequently, the risk of transmission may vary dramatically, depending upon the particular cryptic species present in a given area. The species complex is confined to the Old World and our samples were collected in Southern Africa, Madagascar and the Ivory Coast. Genomic DNA of 350 randomly sampled individual midges from 19 populations was amplified using four 20-mer primers by the random amplified polymorphic DNA (RAPD) technique. One hundred and ninety-six interpretable polymorphic bands were obtained. Species-specific RAPD profiles were defined and for five species diagnostic RAPD fragments were identified. A high degree of polymorphism was detected in the species complex, most of which was observed within populations (from 64 to 76%). Principal coordinate analysis (PCO) and cluster analysis provided an estimate of the degree of variation between and within populations and species. There was substantial concordance between the taxonomies derived from morphological and molecular data. The amount and the different distributions of genetic (RAPD) variation among the taxa can be associated to their life histories, i.e. the abundance and distribution of the larval breeding sites and their seasonality.
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