We observed the muscles of hindlimb, talus, and tarsal joints in the lesser mouse deer (Tragulus javanicus) and greater mouse deer (Tragulus napu) that have conserved the original morphological characters of the musculoskeletal system in the Ruminantia. The proximal trochlea articulating to the distal end of the tibia obviously turned at a medio-proximal direction. Since the proximal parts of the muscle bundles were concentrated in the lateral side of the thigh, the tension of the extensor muscles in the hindlimb is medio-distally conducted. It indicates that the extending power of hindlimb muscles is not parallel with the direction of the trochlea, but crosses the angle of the proximal pulleys in the talus. We suggest that the crossing may enable the animal to stand and run stably and to bear its body weight. We compared the development of the hindlimb muscles in the mouse deer (Tragulus javanicus and Tragulus napu) with that in the Sika deer (Cervus nippon) and Chinese muntjac (Muntiacus reevesi). The dry weight of the muscles in the mouse deer indicated that the mass of the muscles were obviously concentrated in the lateral side of the proximal area and in the cranial side in the distal area in comparison with the two other large-bodied species. We can conclude that the present findings of the hindlimb muscles and talus in the mouse deer indicate the original functional strategy of the locomotion in non-specialized species of the Suborder Ruminantia.

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Fluctuation in the number of Asiatic black bears, Ursus thibetanus, culled in 1993-2004 was analyzed for 25 areas from 23 prefectures in Japan by cluster analysis. The areas were roughly divided into two groups, one consisting of areas west of Toyama, and the other consisting of areas east of Nagano, which was further divided into three clusters. Each cluster was composed of areas (prefectures) that were geographical neighbors except for four areas that were not merged into any clusters. It was likely that the number of culled bears in the residential area was affected by an inter-prefectural factor. These findings kept open the possibility of forecasting the increase of nuisance bears based on hardmast monitoring, although which tree species and how strongly bears depend on them are still unclear. Further monitoring on the number of nuisance bears and hardmast production level is needed.

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The Pallas squirrel, Callosciurus erythraeus, is an introduced species to Japan where a male-biased sex ratio has been reported at the weaning stage in the field. For further examination of their earlier (fetal) sex ratio, a new PCR primer set was designed to amplify a portion of the Sry (sex-determining region Y) gene. This successfully produced sex-specific PCR profiles for known-sex adult samples. Using this technique we could determine the sex of fetal samples dissected out of mothers shot as pests on Izu-Oshima Island, Tokyo, Japan. The fetal sex ratio was significantly male-biased in 2000, but not in other years. The sex ratio tending towards male-bias in this squirrel is discussed from a local resource competition theory.

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To examine the relationship between the annual variation in agricultural crop consumption by bears and the fluctuation in acorn production from 1994-1997, we investigated the diet of Hokkaido brown bears (Ursus arctos yesoensis) in the Tokyo University Forest in central Hokkaido, Japan, using scat content analysis, and estimated Quercus crispula acorn production using seed traps. Scat analyses revealed seasonal changes in the diet of bears; the dominant food items were forbs with small numbers of ants in early summer, crops in late summer, and berries and Q. crispula acorns in autumn. Acorn production fluctuated annually throughout the study and was highest in 1994 and lowest in 1995. From September through November 1995, the frequency of occurrence of acorns was lower, and that of crops was higher, than in the other years. We found a negative correlation between the difference in the same month of the previous year in percent volume of crops in the diet and that in acorn production in September through October, 1994-1997. In years of low acorn production, brown bears used crops as an alternative food source from September through November, although there was no significant difference in August.

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We present the first karyological study on Kloss's mole Euroscaptor klossi from Chiang Rai Province of Thailand. We used differential chromosome staining methods and determined the diploid and fundamental autosomal numbers to be 36 and 54, respectively. Compared with the G- and C-banded karyotypes of the Japanese mountain mole E. mizura, the karyotype of E. klossi involved a reciprocal translocation followed by a pericentric inversion of chromosomes 1 and 16 of the ancestral karyotype of E. mizura. Some minor C-band duplications supplemented the karyological differences between the two species. The karyotype of E. klossi is distinct from that of the Malaysian mole E. micrura malayana examined previously and these species have distinct scenarios in diverging from the ancestral karyotype of the genus Euroscaptor.

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