I examined the feeding rates and feeding niches of regular partcipating species of avian mixd-species flocks in a western forest of Madagascar in different social situations. The regular species were, Crested Drongo, Common Newtonia, Madagascar Paradise Flycatcher, Rufous Vanga, Blue Vanga, Long-billed Greenbul and Ashy Cuckoo Shrike. All of the species responded differently to mixed-flocking and thus it is suggested that the effects of association varied among species. The changing of feeding sites and/or technique was found in six species, five of which increased feeding rates. When participating in mixed flocks, they tended to use similar height and increased variations of location and/or technique. The interspecific convergence enhancing feeding rate, contrary to that expected from a competition may be explained from a social learning effect. The effect appeared to be greatest in Drongo, which increased feeding efficiency by changing not only foraging habits but also prey menu when foraging with other species. In Drongo, kleptoparasitism also appeared to contribut to increase feeding effisiency in mixed-flocks. Paradise Flycatcher also benefitted much from foraging in mixed flocks by a beating effect. The two species' consistently-following tactics in mixed-flocks is greatly paid through these effects. Although Newtonia and Greenbul often attracted other species as leaders, then, they increased feeding rates through some mutualistic effects. Rufous Vanga was the only species that changed neither feeding habits and feeding efficiency in different social situations. Most individuals of this species foraged in cohesive conspecific breeding groups, and frequently gave alarm calls and even direct attacks against predators. These characteristics of Rufous Vanga suggest that its conspecific groups moved independently of other species and that its association with heterospecifics probably resulted from other species following it to exploit its ability to detect predators.

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Hoarding behaviour of Japanese squirrels (Sciurus lis Temminck) was studied using walnuts (Juglans airanthifolia Carr.) attached radio transmitters. A hundred of walnut seeds were provided on the feeding stands in the walnut forest from September to December of 1992. Squirrels immediately ate 35 walnuts near the feeding stand, and 60 of them were scatter-hoarded. The hoarding site tended to be upper part of the slope than the feeding stand. The distance from the feeding stand to hoarding sites ranged from 1-62m. Thirty-eight of hoarded walnuts were retrieved by squirrels later, but 15 were stolen by wood mice (Apodemus speciosus Temminck). Consequently, 7 of them were left at the hoarded site until May, 1993, when starting the germination. The scatter-hoarding by Japanese squirrels had an important role for seed dispersion of walnuts.

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The relationship between animal-dispersed plants and frugivorous animals was observed in a warm temperate evergreen forest on Yakushima Island from following four viewpoints.
1. Fruiting phenology. Some of the observed consumers were year-round residents, but the most of consumers migrated to Yakushima Island from the main islands of Japan to over winter (from November to March), and their abundance in winter was four times as high as during the rest of the year. In 23 of 27 plant species investigated sapfruit production coincided with their immigration season.
2. Feeding patterns of frugivores. Sapfruits were consumed by birds and Japanese macaques. Birds with small gapes consumed only small fruits (less than 6mm in diameter); while birds with large gapes and Japanese macaques consumed a wide range of fruits (from 4 to 16mm in diameter). The larger animals did not ignore the smaller fruits.
3. The spatial distribution patterns of dispersed seeds, saplings and fruiting trees. As for species whose seeds were dispersed only by gravity, the distributions of seeds and saplings were restricted within the narrow area around fruiting trees. Seeds of sapfruits were dispersed widely by birds and monkeys. The distribution of saplings of these species were concentrated but differ from the area around fruiting trees.
4. Eight-year fluctuations of fruit production. Total numbers of sapfruits or capsules fluctuated in eight years for each species. Fruiting fluctuations of these species were assorted in tree types. The degree of fluctuations of annual fruiting species and biennial fruiting species was smaller than that of nuts previously reported, but there were no significant difference between the degree of mass fruiting species and that of nuts. For every species except two species great fruiting years tended to coincide among individuals within a species. Great fruiting year among inter species showed mild synchronization.

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This paper re-evaluates food-sharing in Pan societies from a sociological perspective, with the purpose of creating a better model of food-sharing in human ancestors.
A chimpanzee begging food from another will never attack the other nor snatch the food away, even if begging is ignored. Thus, when a food possessor allows beggars to take food, it is not forced but rather voluntary behavior worthy to the term food-sharing. A food-possessor tends to share smaller portion of food, indicating consciousness of sharing and conflict in abandoning desire.
Food-sharing suggests the following implications for social evolution. 1) The beginning of intervention by others into the self-maintaining activities of an independent individual. 2) The first form of interaction through the medium of material objects. 3) The voluntary abandonment of desire, made possible through self-consciousness and the capacity to view oneself objectively. 4) The capacity to sence another's desire as one would one's own, a psychological capacity that is the basis of intersubjectivity. 5) A rudimentary form of economics, in which food takes on value and is possessed, although it soon disappears.
In this way, advent of food-sharing in the common ancestor of Pan and Homo was linked to great changes in social structure, relations and recognition. It was a jump comparable to advent of reciprocity and systematic food-sharing.

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Since the study of mithocondrial DNA regarding the origin of modern humans, the fate of the Neandertal has been debated. Currently, two famous models are present such as the Out of Africa model and the Multiregional Evolution model.
This papar reviewed the past and current studies of morphological research on the Neandertal and the new dating of the several sites in Europe and Mddle East. Also, tested the ecological theory of symbiosis hypothesis (mutualism and commensalism) and competition hypothesis (habitat segregation and food segregation). Only Out of Africa model is applicable to both symbiosis hypothesis and competition hypothesis.
The present author favored the competition hypothesis.

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Even today, historical and/or archaeological arguments on the origins of agriculture have been deeply affected by themythical stories of archaic societies. If we wish to change this argument to a scientific one we have to establish ecological approaches on this theme. From the ecological standpoint agriculture and/or cultivation is a kind of symbiotic relationship which are observed between manykinds of creatures. In the ecological sense, the basic models on the origins of agriculture and/or cultivation should be applicable to a wider range of symbiotic relationships which are practiced by many kinds of creatures include humans.

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