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71.
Yoshi Kawamoto Hiroyuki Takemoto Shoko Higuchi Tetsuya Sakamaki John A. Hart Terese B. Hart Nahoko Tokuyama Gay E. Reinartz Patrick Guislain Jef Dupain Amy K. Cobden Mbangi N. Mulavwa Kumugo Yangozene Serge Darroze Céline Devos Takeshi Furuichi 《PloS one》2013,8(3)
Bonobos (Pan paniscus) inhabit regions south of the Congo River including all areas between its southerly tributaries. To investigate the genetic diversity and evolutionary relationship among bonobo populations, we sequenced mitochondrial DNA from 376 fecal samples collected in seven study populations located within the eastern and western limits of the species’ range. In 136 effective samples from different individuals (range: 7–37 per population), we distinguished 54 haplotypes in six clades (A1, A2, B1, B2, C, D), which included a newly identified clade (D). MtDNA haplotypes were regionally clustered; 83 percent of haplotypes were locality-specific. The distribution of haplotypes across populations and the genetic diversity within populations thus showed highly geographical patterns. Using population distance measures, seven populations were categorized in three clusters: the east, central, and west cohorts. Although further elucidation of historical changes in the geological setting is required, the geographical patterns of genetic diversity seem to be shaped by paleoenvironmental changes during the Pleistocene. The present day riverine barriers appeared to have a weak effect on gene flow among populations, except for the Lomami River, which separates the TL2 population from the others. The central cohort preserves a high genetic diversity, and two unique clades of haplotypes were found in the Wamba/Iyondji populations in the central cohort and in the TL2 population in the eastern cohort respectively. This knowledge may contribute to the planning of bonobo conservation. 相似文献
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Eri Miyazawa Akiko Seguchi Nana Takahashi Ayumi Motai Ei-Ichi Izawa 《Ethology : formerly Zeitschrift fur Tierpsychologie》2020,126(2):195-206
Allogrooming, where an individual grooms another, has been extensively studied in various social animals to understand its role in the evolution of cooperation/prosociality. In existing studies in mammals, allogrooming has been suggested to exhibit not only a hygiene but also a social function. Allopreening, a topic of increasing interest in mammals but recently also in birds, has been studied mostly with mature animals. However, in some species immature individuals also show allopreening and its function remains poorly understood. Crows, Corvus spp., are an ideal model to study this phenomenon, because juveniles form year-round aggregates during their long juvenile stage (e.g., throughout 3–4 years). Here, we investigated the function of allopreening in juvenile groups of wild-caught large-billed crows (C. macrorhynchos). Allopreening frequency and duration for three groups of wild-caught juveniles were analysed to determine whether there was a symmetrical (i.e., reciprocal) or asymmetrical allopreening pattern, and if sex composition of the dyad and/or relative dominance of donor and recipient had an effect. We found that both the frequency and duration of male allopreening correlated with frequency of aggression. Allopreening between both males and females occurred unidirectionally from dominants to subordinates but not in the opposite direction. On the contrary, allopreening between a male and a female was found to be reciprocated, though the absolute frequency and duration were both greater in males than in females. These results suggest that the social function of allopreening in juvenile crows differs depending on the sex composition of the dyad, functioning as a dominance signal for same-sex dyads, and serving a social bonding function for opposite-sex dyads. These findings may reflect the potentially crucial roles of allopreening in within-sex competition and opposite-sex attraction during the 3 year-long juvenile stage affecting future mate choice in lifelong monogamy. 相似文献
75.
Yasuda Tetsuya Mishiro Koji Kusunoki Mikio Fujiwara-Tsujii Nao Yasui Hiroe Uechi Nami Fujimura Takako Inokuchi Rika Fujita Kiwamu Kanegae Yasutada Miura Yasushi Kato Ichiro Mitsunaga Takayuki 《Applied Entomology and Zoology》2020,55(2):205-212
Applied Entomology and Zoology - To evaluate the infection risk of Anoplophora malasiaca (Thomson) (Coleoptera: Cerambycidae) in two species of Japanese pine bonsais (Japanese black pine and... 相似文献
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Michio Nakamura Nadia Corp Mariko Fujimoto Shiho Fujita Shunkichi Hanamura Hitoshige Hayaki Kazuhiko Hosaka Michael A. Huffman Agumi Inaba Eiji Inoue Noriko Itoh Nobuyuki Kutsukake Mieko Kiyono-Fuse Takanori Kooriyama Linda F. Marchant Akiko Matsumoto-Oda Takahisa Matsusaka William C. McGrew John C. Mitani Hitonaru Nishie Koshi Norikoshi Tetsuya Sakamaki Masaki Shimada Linda A. Turner James V. Wakibara Koichiro Zamma 《Primates; journal of primatology》2013,54(2):171-182
We have analyzed the ranging patterns of the Mimikire group (M group) of chimpanzees in the Mahale Mountains National Park, Tanzania. During 16 years, the chimpanzees moved over a total area of 25.2 or 27.4 km2, as estimated by the grid-cell or minimum convex polygon (MCP) methods, respectively. Annually, the M group used an average of 18.4 km2, or approximately 70 %, of the total home-range area. The chimpanzees had used 80 % of their total home range after 5 years and 95 % after 11 years. M group chimpanzees were observed more than half of the time in areas that composed only 15 % of their total home range. Thus, they typically moved over limited areas, visiting other parts of their range only occasionally. On average, the chimpanzees used 7.6 km2 (in MCP) per month. Mean monthly range size was smallest at the end of the rainy season and largest at the end of the dry season, but there was much variability from year to year. The chimpanzees used many of the same areas every year when Saba comorensis fruits were abundant between August and January. In contrast, the chimpanzees used several different areas of their range in June. Here range overlap between years was relatively small. Over the 16 years of the study we found that the M group reduced their use of the northern part of their range and increased their frequency of visits to the eastern mountainous side of their home range. Changes in home-range size correlated positively with the number of adult females but not with the number of adult males. This finding does not support a prediction of the male-defended territory model proposed for some East African chimpanzee unit-groups. 相似文献
78.
Takashi Sakudoh Seigo Kuwazaki Tetsuya Iizuka Junko Narukawa Kimiko Yamamoto Keiro Uchino Hideki Sezutsu Yutaka Banno Kozo Tsuchida 《Journal of lipid research》2013,54(2):482-495
Dietary carotenoids are absorbed in the intestine and delivered to various tissues by circulating lipoproteins; however, the mechanism underlying selective delivery of different carotenoid species to individual tissues remains elusive. The products of the Yellow cocoon (C) gene and the Flesh (F) gene of the silkworm Bombyx mori determine the selectivity for transport of lutein and β-carotene, respectively, to the silk gland. We previously showed that the C gene encodes Cameo2, a CD36 family member, which is thought to function as a transmembrane lipoprotein receptor. Here, we elucidated the molecular identity of the F gene product by positional cloning, as SCRB15, a paralog of Cameo2 with 26% amino acid identity. In the F mutant, SCRB15 mRNA structure was severely disrupted, due to a 1.4 kb genomic insertion in a coding exon. Transgenic expression of SCRB15 in the middle silk gland using the binary GAL4-UAS expression system enhanced selective β-carotene uptake by the middle silk gland, while transgenic expression of Cameo2 enhanced selective lutein uptake under the same GAL4 driver. Our findings indicate that divergence of genes in the CD36 family determines the selectivity of carotenoid species uptake by silk gland tissue and that CD36-homologous proteins can discriminate among carotenoid species. 相似文献
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Koji Ueda Keitaro Tawaraya Hideki Murayama Satoru Sato Takashi Nishizawa Tomonobu Toyomasu Tetsuya Murayama Shinpei Shiozawa Hironori Yasuda 《Applied Entomology and Zoology》2013,48(1):79-85
We investigated the effects of symbiotic association between a plant and an arbuscular mycorrhizal fungus (AMF) on the abundance of aboveground foliar-feeding insects that differed in feeding mode and their predator. We examined effects on insect abundance as the result of AMF-related changes in the quality and quantity of plants in the field. The numbers of three insects with different foliar-feeding mode (phloem feeder, chewer, and cell-content feeder) and their generalist predator Orius sauteri Poppius on soybean Glycine max (L.) Merrill with and without the AMF Gigaspora margarita Becker & Hall were compared over time. Symbiotic association between the AMF and the soybean increased shoot biomass, the concentration of phosphorus in the soybean, and the abundance of the phloem feeder Aulacorthum solani Kaltenbach, but did not affect the abundance of generalist chewers. In addition, the effects of the symbiotic association on the abundance of cell-content feeding Thrips spp. and the generalist predator O. sauteri differed between sample dates. These results indicated that the effects of the symbiotic association on the number of foliar-feeding insects depended on feeding mode and the number of predators. 相似文献