To examine the genetic origin of the domestic pig, the distribution of wild boar, and human-mediated translocation of the domestic pig, we collected 223 samples from domestic pigs and wild boars from eight Indonesian islands, sequenced the control region of mitochondrial DNA (mtDNA) from each sample, and compared these sequences with previously determined sequences from East and Southeast Asian domestic pigs and wild boars. Three Sus species (S. scrofa, S. verrucosus, and S. celebensis) were identified on the Indonesian islands. The mtDNA sequences of three Indonesian Sus species were diverse, and they clustered into three lineages with low bootstrap values (an S. scrofa group including East and Southeast Asian domestic pigs and wild boars, a group including indigenous S. scrofa together with S. verrucosus from Sumatra and Java Islands, and an S. celebensis group from Sulawesi Island). The mtDNA haplotypes of S. scrofa wild boars from three (Sumbawa, Flores and New Guinea) islands and domestic pigs from two (Lombok and Timor) islands east of the Wallace Line, and some S. scrofa wild boars from Sumatra and Java Islands were related to Vietnamese pig mtDNA sequences in the East and Southeast Asian domestic pig and wild boar clade, supporting that ancient immigrants likely introduced domestic pigs from the Asian continent to east Indonesian islands. The mtDNA haplotypes of S. celebensis were broadly divided into three groups, which were distributed in the north and southwest areas, central area and southeast area of Sulawesi Island.

Genetic variations and their relationships to individual fitness have been the major topics in studies of ecology and evolution. The concept that a reduction in genetic variations leads to lower fecundity termed “inbreeding depression” has been predominantly supported by studies involving laboratory organisms, but has rarely been tested in wild populations. We therefore examined whether the individual genetic diversity among a population of wild sika deer (Cervus nippon) on Kinkazan Island, northern Japan, affected neonatal weight that is often considered as a fitness-related trait. First, the neonatal weights of fawns born during 1994–2004 were recorded, and 11 microsatellite loci were genotyped to obtain 5 different estimates of an individual's genetic diversity. To test whether the genetic diversities of fawns correlated with their neonatal weights, multivariate analyses using a generalized linear mixed model were performed. The neonatal weights were significantly affected by standardized multilocus heterozygosity and mother's body condition, as well as the interaction of these factors. Interestingly, the model indicated that neonatal weight was positively correlated with the genetic diversities of fawns only when the mothers' body weight exceeded a certain level that varies according to their reproductive history.

We studied the relationships between movement and foraging habits of the Asiatic black bear (Ursus thibetanus) and hard mast production of five tree species in cool temperate forest during 2006–2008. The purpose of this study was to test the hypothesis that low mast production affects sexual differences in bear behavior. We summarized the movement pattern of 13 bears in terms of minimum movement distance and cumulative movement distance of the movement path followed during 24 hour. Masting of Quercus crispula acorns was low in 2006, high in 2007 and moderate in 2008. The dominant food items found in bear scats were hard mast, especially Quercus acorns. The percentage of Quercus acorns in the food items in scats was higher in 2007 than in 2006 and 2008. Movement distance of males and females increased in the low mast year. However, the increase of movement distance of females was larger than that of males. Thus, masting influenced the behavior of females more strongly than males. Our results indicated that low mast production changed the food habits and the size of the home range of bears, especially of females.

Male brown bears (Ursus arctos) generally disperse over longer distances than females, which have conservative habitats around their natal areas. Our previous study indicated that the distributions of mitochondrial DNA (mtDNA) subhaplotypes in females were allopatric in the southern Akan—Shiranuka region of eastern Hokkaido. Dispersal of males from their natal area to another natal area is easily detected from the allopatric distributions of two of the mtDNA subhaplotypes of female bears (HB02a and HB13b). Here, to investigate the effectiveness of gene flow and dispersal of male bears between two natal areas, we assessed the genetic diversity and kinship of 132 brown bears from 1996 and 2008 in this area by analyzing the polymorphisms of mtDNA and microsatellite DNA. Parentage testing revealed that there were 48 potential father—offspring pairs, nine potential mother—offspring pairs, and four potential parent—offspring trios. Among 33 of the 48 father—offspring pairs, the mtDNA subhaplotypes differed between father and offspring, suggesting that these potential fathers moved from one natal area to the other and had reproductive success. The results show that effective dispersal of male bears has maintained the genetic diversity and gene flow between the two natal areas.