Interactions between organisms and allelochemicals in space have been not well investigated. We employed a 3D-clinorotation device to generate pseudo-microgravity in order to answer this question. If any allelopathy associated biosynthesis, emission, transport and sensing mechanism is found to be gravity dependent, many organisms and ecological systems might exhibit a different behavior under the microgravity experienced in space. The sunflower (Helianthus annuus L.) is known to show strong allelopathic properties against other plant species. The growth of lettuce seedlings, as an index of the allelopathic action, was compared between the 3D-clinostated group and a control group cultivated in normal gravity. The degree of suppression of the lettuce growth by the sunflower plant was found to be less in the experiment group. Sundiversifolide,4,15-dinor-3-hydroxy-1(5)-xanthene-12,8-olide, has been isolated and identified from the exudate of seeds (achenes) of the Taiyo sunflower as a new plant species-specific allelopathic substance (Ohno et al., 2001). The occurrence of this substance was remarkably different under normal gravity vs. the pseudo-microgravity. It was found that sundiversifolide was not a stable compound and it became a non-active substance, which did not have any inhibitory activity on the shoot lengths of lettuce seedlings after adding the extraction from the achenes. These results indicate that the synthesis and release of the allelochemicals are reduced under pseudo-microgravity.

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In gravitropism of Arabidopsis root, the Arabidopsis root proteins induced and/or changed by gravitational stimulation were analyzed using a proteomic method. In this study, it was found that the levels of expression of some proteins related to the cytoskeleton and the calcium signal transmission system had changed during gravitational stimulation. In addition, the β subunit of the E1 component of pyruvate dehydrogenase, fructose bisphosphate aldolase, and 20S proteasome β subunit E1 protein appeared in two different molecular weight types during gravitational stimulation. The transitory changes in molecular weight in these three identified proteins were important findings although their functions in the gravity response in the roots of Arabidopsis seedlings remain uncertain. As far as we know, this is the first study involving the molecular weight shift-change in the same protein during the gravitropism response in plants using proteomic analysis.

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We identified the aspect(s) of growth and development in the life cycle that are affected by hypergravity using an experimental model animal Caenorhabditis elegans. More than 100 G hypergravity decreased the hatching (survival) rate of eggs laid by adult hermaphrodites but had little effect on the brood size. Polar bodies were not excluded in the dead eggs that had been laid under hypergravity. In addition, hypergravity caused abnormal distribution of PAR2 protein that regulates polarization of the anterior-posterior axis. However, when the meiotic divisions following fertilization were allowed to take place at 1 G, after which the gravity was raised to 200 G, the resulting embryos developed normally and grew to adulthood. When adult hermaphrodites cultured at 100 G were transferred to 1 G, the fertilized eggs after the shift developed normally and their hatching rate recovered completely. In addition, at 100 G, the oocytes matured normally, as they showed activation of a MAP kinase MPK1. These results suggest that hypergravity affects a reproductive process, namely, oocyte meiotic division for exclusion of polar bodies and the anterior-posterior polarization, that require meiotic-specific cytoskeletal systems shortly after fertilization, in the C. elegans life cycle.

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What humans turned into humans? This is a fundamental theme of anthropology, and may be ultimate target when we get to know us. However, the theme is also very difficult to explain. Now, only human beings of a kind merely called humans (Homo sapiens sapiens) survive. However, by the time this human is born, there were many processes on the evolution and there was extinction of many kinds of hominids. There are many features which humans have been further acquired from the initial life to the vertebrate in various stages, such as the mammals, the primates, the hominoids and fossil hominids. In other words, they are the stamps which show that it was adapted for the native habitat of the time in each stage. The most fundamental feature that distinguishes an ape and human beings (fossil hominids also including) is bipedal locomotion, and it is supposed that the features peculiar to humans, such as encephalization, use of a tool, and linguistic competence, are progressed after bipedal locomotion is gained. It comes out that the movement style of this bipedal locomotion was acquired in East Africa of 5 million to 8 million years ago, and it is thought under the influence of reduction of the forest by the change of the environment. To move a life place on the ground from a tree must have been a change surprising for the animals. Since not only the problems of the food and habit change, but change arose in the danger of predation or disaster, the family, a social relation, and a locomotion and body structure was further influenced with regards to them. It may be having the big influence which humans comes to live a life by space separate from the earth, like as the change to terrestrially from arboreality in the near future. I want to consider that humans change how in that case, or that it must change.

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Human nature is a product of human brain activity, and human brain is an organ which functions to assess environmental information and to make decision about what to do next. Many aspects of human nature must be the results of evolution through natural selection in which favorable genes were selected under the environmental stress. Now, we live in civilized societies based on highly developed technology, using computers, contemplating about the relativity theory, mastering the calculus etc. However, this was not an environment where our basic human nature evolved. That environment was the one which surrounded our ancestors. Humans lived as hunter-gatherers in most of the time during evolution, and the human brain evolved to solve those problems confronted at those times. The resulting decision-making algorithms were so flexible that we can now deal with novel problems of our time using the same old decision-making algorithm. The evolution of behavior is a very complex process and no one gene is controlling any particular behavior. Genes are indeed involved in producing adaptive behavior but a behavior is produced through many other pathways as well, such as learning. We have evolved a huge brain which is capable of producing culture. Culture is a human creation but at the same time, culture has become our environment to which we have to adapt. Thus gene-culture coevolution has been a very important process in human evolution. After we have acquired language, perhaps we have acquired an almost unlimited cognitive power. Many of our cultural invention is the results of our cognitive activity and these things have become parts of our environment. However, cognition is only a small part of the workings of our brain. Human nature is also under control of emotion. Emotional processes are mostly subconscious and have changed little through evolutionary time. In the future, misfits between our cognitive products and emotional process may create many difficult problems which we have never experiences so far.

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Even though the market size is still small at this moment, applied fields of robots are gradually spreading from the manufacturing industry to the others in recent years. One can now easily expect that applications of robots will expand into the first and the third industrial fields as one of the important components to support our society in the 21st century. There also raises strong anticipations in Japan that robots for the personal use will coexist with humans and provide supports such as the assistance for the housework, care of the aged and the physically handicapped, since Japan is one the fastest aging societies in the world. Consequently, humanoid robots and/or animaloid robots have been treated as subjects of robotics researches in Japan such as a research tool for human/animal science, an entertainment/mental-commit robot or an assistant/agent for humans in the human living environment. Over the last couple of years, some manufactures including famous global companies started to develop prototypes or even to sell mass production robots for the purposes mentioned above, such as SONY, TMSUK, ZMP, TOYOTA, HONDA, Mitsubishi Heavy, etc. Most of those robots have some lifelikeness in their appearances and behaviors. On the other hand, Waseda University, where we belong to, has been one of the leading research sites on humanoid robot research since the late Prof. Ichiro Kato and his colleagues started the WABOT (WAseda roBOT) Projects and developed the historical humanoid robots that are WABOT-1 and WABOT-2 done in the early 70s and 80s respectively. One of the most important aspects of our research philosophy is as follows: By constructing anthropomorphic/humanoid robots that function and behave like a human, we are attempting to develop a design method of a humanoid robot having human friendliness to coexist with humans naturally and symbiotically, as well as to scientifically build not only the physical model of a human but also the mental model of it from the engineering view point. Based upon the philosophy mentioned above, we have been doing researches on humanoid robots, such as the Biped Walking Robots, Emotion Expression Robots, Mastication Robots, Flute Player Robots, Speech Production Robots, etc. We believe that our research philosophy and methodology on humanoid robot design will be applicable to space robot design and also will give important knowledge and views to space sciences.

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