Pollination of hemiparasites (Loranthaceae) by spider hunters (Nectariniidae) in the canopy of a Bornean tropical rain forest

We observed pollination process of three hemiparasites, Loranthaceae, Amylotheca duthieana (King) Danser, Trithecanthera sparsa Barlow and T. xiphostachys Tiegh. Flowers of these three species were cylindrical with different corolla lengths. Flowers of A. duthieana, T. sparsa and T. xiphostachys were reddish orange, yellow, and pink in color, respectively. Flowers lacked odor, nectar guides, and landing places for visitors. Long-billed spider hunters (Arachnothera robusta) were main visitors to flowers of all three species, although little spider hunters (Arachnothera longirostra) foraged on A. duthieana and T. sparsa in much less frequency. Aggressive behavior of the long-billed spider hunter might have modified the other nectarivorous birds' foraging pattern. Long-billed spider hunters visited A. duthieana flowers only in the early morning, but visited T . sparsa flowers rather constantly from the morning to noon. Flowers of T. xiphostachys were visited by them at most only two times a day. Diurnal patterns of nectar production and nectar level in the corolla fit well to the above visit patterns to these three species. The utilization of pollinators by three species of mistletoes may be partitioned along a diurnal dimension.ArticleSelbyana. 18(1): 51-60(1997)journal articl

PHENOLOGY OF FRUITS CONSUMED BY A SYMPATRIC POPULATION OF GORILLAS AND CHIMPANZEES IN KAHUZIBIEGA NATIONAL PARK, DEMOCRATIC REPUBLIC OF CONGO

Monthly fl uctuations in the abundance of fruits eaten by a sympatric population of gorillas (Gorilla beringei gaueri) and chimpanzees (Pan troglodytes schweinfurthii) were estimated by a transect system and a fruit trail system in the montane forest of Kahuzi-Biega National Park, Democratic Republic of Congo. Fruit species eaten by gorillas and chimpanzees and their preferences were defi ned mainly by fecal analysis. Data were collected for 80 months from 1994 to 2002, with a period of forced inactivity due to the civil war in 1997. A belt transect 5, 000 m long and 20 m wide was set up in the study area to pass through most of the vegetation types in which gorillas and chimpanzees range, and 2, 033 trees, including shrubs and strangling fi gs, above 10 cm in diameter at breast height (DBH) of 49 species from 29 families were identifi ed. Of these, fruits of 21 (6) species and 25 (12) species were eaten (preferred) by gorillas and chimpanzees, respectively. The fruit species preferred by gorillas were also preferred by chimpanzees. Monthly fruit index calculated from total basal area per ha and the proportion of the number of trees in fruit for each species shows a larger fl uctuation in the abundance of fruits eaten by chimpanzees than that by gorillas. Unlike the phenology of fruits in the lowland tropical forests, monthly fl uctuation in ripe fruit abundance negatively correlated with rainfall in some years. This tendency was more distinct for fruits preferred by gorillas in the primary forest. Fruit species preferred only by chimpanzees showed a distinct intra-specifi c synchrony in fruiting, while fruit species preferred by gorillas and chimpanzees did not. These differences in fruiting patterns may infl uence the foraging patterns of gorillas and chimpanzees. Gorillas tended to travel widely in a cohesive group and to increase their consumption of fruits in the primary forest during the dry season. By contrast, chimpanzees tended to continuously visit particular fruiting trees individually in a small home range throughout the entire year. Some tree species that have large basal areas and that bear fruits for a long period may be able to support the survival and sympatry of gorillas and chimpanzees

The diet and feeding behavior of the black-and-white colobus (Colobus guereza) in the Kalinzu Forest, Uganda

One of the goals for primate feeding ecology is to understand the factors that affect inter- and intra-specific variations. Therefore, a detailed description of basic feeding ecology in as many populations as possible is necessary and warrants further understanding. The black-and-white colobus (Colobus guereza) or guereza is widely distributed in Africa and is one of the well-studied colobines in terms of their feeding; they demonstrate considerable variation in their diets in response to local conditions. We studied the diet of a group of guerezas in the Kalinzu Forest, Uganda, for over 30 consecutive months using behavioral observation (4308 h in total), phenology, and vegetation surveys. A total of 31 plant species were consumed by the study group. This study group was predominantly folivorous; the majority of their feeding time was involved in feeding on young leaves (87%). However, during certain times of the year, fruits and seeds accounted for 45% of monthly feeding time. Young leaves of Celtis durandii were by far the most important food, which constituted 58% of the total feeding records. There was a significant increase in the consumption of fruits and flowers once young leaf availability was low, but their consumption of fruits did not significantly increase even when fruit availability was high. Their monthly dietary diversity increased as the number of available plants with young leaves declined, suggesting that much of the dietary diversity in the study group may be attributable to the young leaf portion of their diet. Our findings may help contribute to a better understanding of the dietary adaptations and feeding ecology of guerezas in response to local environmental conditions

「島」の未来像

Islands have been blessed by their unique biota, culture, and language, depending on affluent ecosystem services and subsistence economy. Island life was one of the good examples of a sustainable way of life. But globalization destroyed its subsistence economy and made their lives unsustainable. Trans-disciplinary research is needed to restore and reconstruct island lives as well as ecosystems, in order to utilize the rich biodiversity and cultural diversity of islands for green development as ecotourism, sustainable forestry and fishery, and handicrafts. Local knowledge of islands is a treasure box for future sustainable lives with “low environmental loads and high quality of live”

Strontium isotope evidence of migration and diet in relation to ritual tooth ablation: a case study from the Inariyama Jomon site, Japan

Ritual tooth ablation was extensively practiced among Jomon (Japanese Neolithic) societies in their final phase (ca. 3000-2300 BP). This tradition includes two different tooth ablation patterns, type 4I and type 2C, referring to extraction of the mandibular incisors and canines, respectively. However, the reason for this difference is unclear. Previous carbon and nitrogen stable isotope analysis of human remains from the Inariyama shell mound revealed that type 4I individuals were more dependent on terrestrial resources and type 2C individuals on marine resources. To test this hypothesis, we performed strontium (Sr) isotope (87Sr/86Sr) analyses on the same skeletal remains and on modern plants around the site. Because Sr isotope ratios of plants differ according to the local geology and seawater has a consistent Sr isotope ratio, the Sr isotope ratios of tooth enamel can reveal both migration and diet. Comparing Sr isotope ratios in plants and seawater with those of tooth enamel, we identified four possible immigrants. Type 4I locals had significantly higher Sr isotope ratios than type 2C locals. The ratios of the type 4I and type 2C locals were close to those of terrestrial plants and seawater, respectively, suggesting that type 4I locals had incorporated much Sr from terrestrial resources and type 2C locals from marine resources. These results support the hypothesis that ritual tooth ablation reflects dietary differences throughout an individual’s life, and they suggest possible occupational differentiation among the Jomon people

Carbon and nitrogen stable isotope analysis on the diet of Jomon populations from two coastal regions of Japan

We report on a stable isotope paleodietary reconstruction of Jomon populations in Japan during the Middle to Final Jomon period (ca. 5000–2300 years BP), focusing on dietary differences within and among populations and between regions. Carbon and nitrogen isotope analysis was performed on human and faunal bone collagen from six coastal sites along the Inland Sea in the Sanyo (Ota, Funamoto, and Tsukumo) region and along Mikawa Bay and the Pacific Ocean in the Tokai (Kawaji, Yoshigo, and Inariyama) region. We found that carbon and nitrogen isotope ratios were positively correlated, indicating that the Jomon people consumed a mixed diet of marine (shellfish and marine fish) and terrestrial (C3 plants and terrestrial mammals) protein. In the Ota samples (n = 25, during the Middle Jomon period, 5000–4000 years BP), sex was one of the main reasons for the intra-population dietary variation. Ota males consumed greater amounts of marine food, while Ota females consumed greater amounts of terrestrial food; these dissimilar diets may have been related to the sexual division of labor. Significant inter-population dietary differences were found, which may have been related to differences in age or site location. Notably, the two coastal regions showed clear isotopic differences. Nitrogen isotope ratios of individuals from the Sanyo region were significantly higher than ratios of individuals from the Tokai region. The individuals in the Sanyo region might have consumed a diet high in aquatic foods, particularly high trophic level marine fish, whereas the individuals in the Tokai region might have consumed a lot of marine shellfish. Another possible reason for the regional isotopic difference might have been different baseline of nitrogen isotope ratios of the marine ecosystems