Mahale Mountains National Park (mahale + mountain_national_park)

Distribution by Scientific Domains


Selected Abstracts


Leaf Processing by Wild Chimpanzees: Physically Defended Leaves Reveal Complex Manual Skills

ETHOLOGY, Issue 8 2002
Nadia Corp
The manual processing of eight species of leaf was investigated in the M-group chimpanzees of Mahale Mountains National Park, Tanzania. Leaf species varied in the extent to which physical defences made consumption difficult. In all, 96 distinct techniques for leaf processing were identified, but two species with defended leaves (Ficus asperifolia and F. exasperata) required 2.5 as many techniques as did any of the six undefended species. Moreover, chimpanzees made more multiple leaf detachments, and made more subsequent modifications of the leaves, when dealing with the leaves of these two Ficus species, compared with the undefended leaf species. This greater complexity was associated with evidence of flexible, hierarchical organization of the process: iteration of modules consisting of several processing elements, facultative omission of modules, or substitutions of alternative modules. Comparison with data from mountain gorillas is made, and is consistent with similar cognitive architecture in the two species. We consider that, not only is hierarchical organization currently associated with mechanical difficulty in food processing, but that over evolutionary time-scales difficulties in food processing may have selected for cognitive advance. [source]


Relatedness in wild chimpanzees: Influence of paternity, male philopatry, and demographic factors

AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 3 2008
Eiji Inoue
Abstract In chimpanzees (Pan troglodytes), high-ranking males are expected to have high reproductive success and females typically emigrate upon reaching maturity. Although high average relatedness among males in the same social groups has been assumed, previous reports have indicated that relatedness among males is not necessarily significantly higher than that among females. The paternity of 11 offspring and the relatedness of 50 individuals in the M group of chimpanzees at Mahale Mountains National Park, Tanzania, were investigated using DNA analyses. We determined the fathers of 10 offspring. Two different alpha males sired a total of five offspring, whereas the other males had low reproductive success. The proportion of paternal half-sibling pairs among the 10 offspring was 15.6%. The average relatedness among mature males was significantly higher than that among mature females. The existence of an old male and the long tenure of one alpha male may have contributed to this significant difference. The average dyadic relatedness among mature natal individuals was significantly higher than that in natal-immigrant pairs in which the individuals came from different groups. The average relatedness among immigrant females was similar to that in pairs of natal and immigrant females, suggesting that the immigrants came from various groups. Thus, female transfer acts to maintain low average relatedness within the group. A comparison of our results to those from other study sites suggests that although the average relatedness among adult males does not reach the level of half-siblings, under some circumstances it can exceed the relatedness of females. Am J Phys Anthropol, 2008. © 2008 Wiley-Liss, Inc. [source]


Fecal bacterial diversity of human-habituated wild chimpanzees (Pan troglodytes schweinfurthii) at Mahale Mountains National Park, Western Tanzania

AMERICAN JOURNAL OF PRIMATOLOGY, Issue 7 2010
Brian A. Szekely
Abstract Although the intestinal flora of chimpanzees has not been studied, insight into this dynamic environment can be obtained through studies on their feces. We analyzed fecal samples from human-habituated, wild chimpanzees at Mahale Mountains National Park, Tanzania, and compared microbial community profiles to determine if members of the same social group were similar. Between July and December 2007, we collected fresh fecal samples from 12 individuals: four juveniles, four adolescents, and four adults, including three parent,offspring pairs. Each sample was analyzed using Terminal-Restriction Fragment Length Polymorphism of amplified 16S rRNA genes. Twelve different profiles were generated, having between 1 and 15 Terminal-Restriction Fragments (T-RFs). Overall, a total of 23 different T-RFs were produced. Putative assignments of T-RFs corresponded to the phyla Firmicutes (Clostridia, Bacilli, and Lactobacilli), Bacteroidetes, Tenericutes (Mollicutes Class), Actinobacteria, and Proteobacteria, as well as to uncultured or unidentified organisms. Firmicutes and Bacteroidetes phyla and Mollicutes Class were the most commonly assigned in 11, 8, and 8 of the samples, respectively, with this being the first report of Mollicutes in wild chimpanzees. Principal Components Analysis (PCA) revealed clustering of nine samples, and 80.5% of the diversity was accounted for by three samples. Morisita indices of community similarity ranged between 0.00 and 0.89, with dissimiliarity (<0.5) between most samples when compared two at a time. Our findings suggest that, although phylotypes are common among individuals, profiles among members of the same social group are host-specific. We conclude that factors other than social group, such as kinship and age, may influence fecal bacterial profiles of wild chimpanzees, and recommend that additional studies be conducted. Am. J. Primatol. 72:566,574, 2010. © 2010 Wiley-Liss, Inc. [source]