| Co-Investigator(Kenkyū-buntansha) |
GOTO Shunji Kyoto University, Primate Research Institute, Instructor, 霊長類研究所, 助手 (90093343)
ENOMOTO Tomoo Tokai University, Fac. of Medicine, Associate Professor, 医学部, 助教授 (80056316)
|
|---|
| Budget Amount *help |
¥6,700,000 (Direct Cost: ¥6,700,000)
Fiscal Year 2001: ¥3,100,000 (Direct Cost: ¥3,100,000)
Fiscal Year 2000: ¥3,600,000 (Direct Cost: ¥3,600,000)
|
|---|
| Research Abstract |
The narrow hybrid zone between Macaca tonkeana and M. hecki was found at the isthmus of northern peninsula of Sulawesi. These two species have been presumably contacted and reproduced hybrids for these several hundred years, but monkeys with phenotypicaly intermediate forms can be seen only in the narrow area at the border of these two species. Aiming at elusidating the mechanisms to keep morphological differences between two species despite of possible gene changes, continuous observation of wild hybrid groups was stated focusing on their reproduction, longevity, infant mortality and some other related demographical indexes. Two wild groups were habituated and observed during the period. In the groups most monkeys were suffered skin diseases and also some malformations were recognized. In a year seven births were confirmed in twenty adult females (birth ratio, 35%). Among them two were lost (infant mortality, 29%). Further, three adult females were lost in a year. It is still difficult to conclude, but lower birth ratio, higher infant mortality and higher disappearance ratio of adult females are inferred since the population of another Sulawesi macaque species, M. maurus, that have been continuously observed by us more than ten years indicated better reproduction and longevities. It is presumed that one adult female was dead as the result of long prolaspe of her anus after giving birth. The same case had been also found in 1991 at the same location. It is suggestive that malformation or bad developmental adjustment influence on their longevity. Some juveniles were lost during the period. The loss of juvenile monkeys more than 1 year of age are usually rare. It is, thus, possible that the hybrid sink occur in the hybrid zone between these two species. On the other hand, close inspection of wild M. hecki was done at Tambu, about 100km north of the area.
|
