Distribution and recent expansion of alien macaque species is known in Izu-ohshima Island, offshore the Kantou District, Japan. Using excremental samples, we examined molecular variations in a partial sequence (202 bp) of mitochondrial DNA (mtDNA) non-coding region. Results of sequencing for 24 samples suggested that the exotic species is the Taiwan macaque (Macaca cyclopis) and that there are at least two distinct types of mtDNA in the island. The two types were distributed ubiquitously, one in east and the other in north and west. This distribution pattern may result from differential expansion of two maternal lineages from a zoological park in northeast, one to the south and the other to the north/west. Application and availability of molecular genetic markers for the monitoring of the alien species are discussed.

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One of the primary objectives in the captive management of chimpanzees is to preserve to the greatest extent possible the genetic diversity that still exists in wild gene pools. Furthermore, it is desirable to prevent the occurrence of intersubspecific hybrids. It is possible to sort chimpanzees into their three subspecies (Pan troglodytes verus, P. t. troglodytes, P. t. schweinfurthii) by investigating mitochondrial DNA sequences. Thus, in order to obtain the basic data necessary to establish a future-breeding protocol, we have decided to evaluate the subspecies of all captive chimpanzees living in Japan. At present, a total of 373 animals including 193 known captive-born, 152 known wild-born, and 28 known captive-born from foreign countries have been raised in Japan. Data on the location of capture of most of these apes is unknown. The 249 chimpanzee samples used in the present study were obtained from 43 zoos in Japan. DNA samples from 180 chimpanzees were extracted from follicle-shed hairs: 67 were from blood samples and 2 were from tissues. We used PCR amplification and direct sequencing of the mitochondrial D-loop region. We compared these sequences with chimpanzees of known geographic origin. Finally, the subspecies of 332 chimpanzees that belonged to 217 maternal lineages were identified. The findings clarified that 230 individuals (61.7%) were P. t. verus. Additionally, four chimpanzees were P. t. troglodytes and 15 were P. t. schweinfurthii. The present findings have also confirmed the existence of another previously unrecognized subspecies of chimpanzee in Nigeria (Pan troglodytes vellerosus). Four of the captive chimpanzees we examined are referable to this subspecies. Examination of the registration book of pedigree and DNA data indicated that 56 chimpanzees born in Japan were actually hybrids of these three subspecies. Molecular data must be carefully examined and reconciled in order to establish a viable breeding plan for chimpanzees in Japan.

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Influences of affinity and lengths of separation on greeting behaviors were examined in a group of captive chimpanzees. According to Nishida et al. (1999), the greeting behaviors were defined as affiliative interactions, such as embrace, kiss, inspect genitals, in this study. The most important factor which enhances the frequency of greeting behaviors among females was being separated, and the second one was high score of the proximity index while the influence of lengths of separation was not detected. These findings supported Nishida’s (1970) hypothesis that “the greeting behaviors of chimpanzees had the function of continuing social bond among group members who did not always range together”.

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The Saguinus oedipus group often has the sagittal crest in cranium, whereas the Amazonian tamarins possess no crest. This suggests that the former may be more developed than the latter in cranial dimensions related to the temporalis muscle. I choosed bizygomatic breadth (left zygion-right zygion), braincase breadth (left euryon-right euryon) and postorbital breadth (left frontosteion-right frontosteion) for the cranial dimensions, and S. geoffroyi and S. mystax for representatives of the S. oedipus group and Amazonian tamarins, respectively. I also measured maximum cranial length (prosthion - opisthocranion) for an indicator of the cranial size. S. geoffroyi has wider bizygomatic breadth relative to maximum cranial length than S. mystax, whereas the differences between the tamarins are insignificant in the postorbital breadth and braincase breadth. Thus, expansion of the zygomatic arch provides a space for enlargement of the temporalis muscles in S. geoffroyi, although males of Cebus apella, which have convergent temporal lines, obtain the larger space by deepening anterior part of the temporal fossa.

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