The skeletal remains of five adult wild chimpanzees (Pan troglodytes schweinfurthii) stored at the Kansyana Research Camp in the Mahale Mountains National Park, Tanzania, were examined in order to identify the skeletons and to find pathological evidence on the bones. In Mahale, wild chimpanzees have been studied for nearly 40 years without interruption . Reference cards of chimpanzees for personal identification in life are now available at the camp. By contrasting morphological and pathological characteristics of the skeletons with the datum on the reference cards, two formerly unidentified skeletons could both be identified. Furthermore, the cause of death of a female chimpanzee was revealed from the skeletal evidence. Postmortem phenomenon of the body and what kinds of records in life are useful for the purpose of identification of the skeletons are discussed. Lastly, the prospect of such a study as a part of the long-term study of wild primates is discussed.

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Hand grasping is one of the unique characteristics of primates. This study reviews our current understandings on hand shape and grasping from two aspects: changes of hand structure in the fossil record, and the significance of hand grasping in arboreal life.
Plesiadapiformes, the sister group of modern primates, exhibits reduction of the relative lengths of matacarpals and distal phalanges within the manus and possesses a widely divergent hallux.The transformation of nails from claws on the all fingers and the appearance of opposability in the hallux occurred after the acquisition of these morphologies. Early in Euprimate evolution, strepsirhines are characterized by wider inter-digit-ray angles and proportionately shorter metacarpals, while haplorhines have nearly parallel metacarpals associated with the development of mesaxony. The latter is more similar to the ancestral condition of Euprimates based on comparisons with other mammals .
The unique characteristics of primates were explained in ambiguous terms as arboreal adaptations ("arboreal theory") until the 1960′s.Subsequent hypotheses, "visual predation theory" and "angiosperm theory", have attempted to correlate these characteristics with specific arboreal activities. It was proposed that hand grasping ability evolved in the primate ancestor because it was beneficial for stabilizing the body and for accomplishing predation at terminal branches. This explanation is based on hand grasping behavior that is also employed by some extant non-primate mammals that make use of terminal branches. Comparisons with other arboreal mammals which have grasping hands and with mechanical models have shown that longer proximal and middle phalanges and shorter distal phalanges relative to metacarpals are required for grasping narrow branches. The fact that the phalangeal ratio change occurred prior to other structural changes typically advanced as critical features in primate evolution clarifies the importance of these characteristics in acquisition of hand grasping ability, a feature that evolved in Plesiadpiformes approximately 55 million years ago.

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We reported one case of parturition behavior and five other cases of maternal behaviors which were rarely observed in a free-ranging group of Japanese monkeys (Macaca fuscata). An eight-year-old female spent more than 3 hours alone before delivery and almost 2 hours afterwards, without being approached by any other group members. The frequency and duration of constractions gradually increased, and the female frequently touched her vulva and perineal region with the fingers of her hand, as the time for delivery grew near. She started to approach other group members about 2 hours after the delivery.
A nine-year-old female did not hold her first newborn to her ventrum after parturition, but walked bipedally, grasping the newborn with both hands. These inappropriate maternal behaviors disappeared the following day. An 11-year-old female carried her newborn ventrally and her yearling dorsally at the same time. This simultaneous carrying of two offspring was recorded for only the first five days after the birth of the newborn. Two other females allowed their one-year-old offspring to nurse after their newborn infant died within two weeks of the infant's life. Moreover, a 13-year-old multiparous female with a four-week-old newborn adopted a week-old newborn and took care of both in the same manner.

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The present paper reports the death of wild chimpanzees through a flu-like epidemic at Bossou, Guinea, West Africa. The community at Bossou has been studied continuously since 1976. Records from the past 28 years show that the number of chimpanzees in the Bossou community has been relatively stable, at around 20 individuals. In late November 2003, chimpanzees at Bossou began to cough. Within a month, five chimpanzees died: two very old females, one adolescent male, and two infants. The mothers of the two dead infants continued to carry the corpses, which eventually mummified. One mother used a stick to chase flies away from the dead infant's body in addition to using her hands. The transportation of infants' mummified bodies may be yet another example of cultural behavior unique to this community. A 12 year-old young mother, who lost her first offspring in this epidemic, remained with the community for two months following the death of the infant, after which she disappeared, most likely immigrating to a neighboring community. We inspected the year-by-year change of age-sex composition in the Bossou community. This revealed that the proportion of old members gradually increased while many young members immigrated. Such a gradual change in the population in addition to the epidemic suggests that this community is in serious danger. The paper also introduces our conservation efforts to attempt to save this important community: the "Green corridor project" which entails the planting of trees in the surrounding savanna in order to create a passage between Bossou and the Nimba Mountains, 4 km away. This might be a model case of connecting chimpanzee habitats that have become isolated through increasing human activity, a very common problem in West Africa.

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