Publications by authors named "Takakazu Yumoto"

Fruit availability experienced by different primate species is likely to vary due to species-specific fruit use, even within the same habitat and timeframe. Pitheciines, primates of the subfamily Pitheciinae, particularly favor the seeds of unripe fruits. Researchers consider this dietary characteristic an adaptation to increase access to fruit resources.

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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.

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While many tropical countries are experiencing rapid deforestation, some have experienced forest transition (FT) from net deforestation to net reforestation. Numerous studies have identified causative factors of FT, among which forest scarcity has been considered as a prerequisite for FT. In fact, in SE Asia, the Philippines, Thailand and Viet Nam, which experienced FT since 1990, exhibited a lower remaining forest area (30±8%) than the other five countries (68±6%, Cambodia, Indonesia, Laos, Malaysia, and Myanmar) where forest loss continues.

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Free-living animals must make dietary choices in terms of chemical and physical properties, depending on their digestive physiology and availability of food resources. Here we comprehensively evaluated the dietary choices of proboscis monkeys (Nasalis larvatus) consuming young leaves. We analysed the data for leaf toughness and digestibility measured by an in vitro gas production method, in addition to previously reported data on nutrient composition.

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The globalization of food production and distribution has homogenized human dietary patterns irrespective of geography, but it is uncertain how far this homogenization has progressed. This study investigated the carbon and nitrogen isotope ratios in the scalp hair of 1305 contemporary Japanese and found values of -19.4 ± 0.

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Understanding the habitat requirements of great apes is essential for effective conservation strategies. We examined annual habitat use of a bonobo group in the Wamba field site within the Luo Scientific Reserve, Democratic Republic of the Congo. Using satellite imagery, we categorized the group's ranging area into three forest types: (1) primary and old secondary forest (P/OS), (2) young secondary forest and agriculture (YS/Ag), and (3) swamp forest (Sw).

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Despite the widespread use of seed/litter traps in seed dispersal ecology, several problems have arisen when using this method in forests inhabited by semi-terrestrial monkeys. The first issue is the height of the trap relative to the location where macaques spit seeds and/or defecate. For Japanese macaques in the lowland forests of Yakushima Island, southern Japan, 30-50% of the seeds emitted from cheek pouches and faeces will not be caught by seed traps, leading to underestimation of seed fall.

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How has the degradation of Abies veitchii wave-regeneration occurred under the sika deer (Cervus nippon) pressure? We conducted tree census and ground vegetation survey in a 1 ha plot in Mt. Misen (Nara prefecture, Japan). We found 15 tree species (over 50 cm in height).

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Article Synopsis
  • Researchers studied how vegetation changes along environmental gradients in a mountainous zone by surveying 360 plots, focusing on various factors like elevation and light.
  • They found that tree species richness decreases with elevation, while fern and herb species richness increase; different vegetation types thrive at different slope areas.
  • The study concluded that elevation and topography are crucial for defining plant richness, but the impact varies among ferns, herbs, and trees.
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We investigated the genetic structure of Sciadopitys verticillata, an endemic conifer in Japan, using 11 microsatellite markers. Average expected heterozygosity varied from 0.282 to 0.

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We investigated the seedling survival of five evergreen tree species over 3 years inside and outside deer-exclusion fences in a warm temperate evergreen broad-leaved forest on Yakushima Island, Japan. Seedling survival was examined in relation to topography, herbivory by sika deer, and the soil surface environment (i.e.

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Taxonomical classification of higher fungi remains an important challenge and can benefit from the application of molecular analysis. We propose that the ectomycorrhizal (EM) fungal taxa might include a number of cryptic species because there are few morphological characteristics useful for distinguishing among these fungi. Previously, host specificity in most EM fungi was thought to be low, but we suspect that confusion of cryptic species has led to an underestimate of fungal host specificity.

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We have investigated tree distributions in relation to topography between different tree life history stages, from the seed-dispersal stage to the adult stage in a warm temperate evergreen broadleaved forest on Yakushima Island, Japan, to clarify the critical stages in determining adult tree distributions. We conducted a census of all living trees > or =30 cm tall and collected seed falls over three years using 25 seed traps in a 50 m x 50 m quadrat. Four life stages were defined: stage 1, dispersed seed; stage 2, individuals taller than 30 cm and diameter at breast height (DBH) < 1 cm; stage 3, trunks 1 cm < or = DBH < 10 cm; stage 4, trunks with DBH > or = 10 cm.

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Large frugivores are considered to be important seed dispersers for many tropical plant species. Their roles as seed dispersers are not well known in Southeast Asia, where degraded landscapes typically lack these animals. Interactions between 259 (65 families) vertebrate-dispersed fruits and frugivorous animals (including 7 species of bulbul, 1 species of pigeon, 4 species of hornbill, 2 species of squirrel, 3 species of civet, 2 species of gibbon, 1 species of macaque, 2 species of bear, 2 species of deer, and 1 species of elephant) were studied for 3 years in a tropical seasonal forest in Khao Yai National Park, Thailand.

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