Exploiting the skills of others enables individuals to reduce the risks and costs of resource innovation. Social corvids are known to possess sophisticated social and physical cognitive abilities. However, their capacity for imitative learning and its inter-individual transmission pattern remains mostly unexamined. Here we demonstrate the large-billed crows' ability to learn problem-solving techniques by observation and the dominance-dependent pattern in which this technique is transmitted. Crows were allowed to observe one of two box-opening behaviours performed by a dominant or subordinate (...) demonstrator and then tested regarding action and technique. The observers successfully opened the box on their first attempts by using non-matching actions but matching techniques to those observed, suggesting emulation. In the subsequent test sessions, dominant observers (i.e. those dominant to the bird acting as demonstrator) consistently used the learned technique, whereas subordinates (i.e. those subordinate to the bird acting as demonstrator) learned alternative techniques by explorative trial and error. Our findings demonstrate crows' capacity to learn by observing behaviours and the effect of dominance on transmission patterns of behavioural skills. Keywords: social learning; imitation; emulation; affordance; culture; innovation. (shrink)

Exploiting the skills of others enables individuals to reduce the risks and costs of resource innovation. Social corvids are known to possess sophisticated social and physical cognitive abilities. However, their capacity for imitative learning and its inter-individual transmission pattern remains mostly unexamined. Here we demonstrate the large-billed crows' ability to learn problem-solving techniques by observation and the dominance-dependent pattern in which this technique is transmitted. Crows were allowed to observe one of two box-opening behaviours performed by a dominant or subordinate (...) demonstrator and then tested regarding action and technique. The observers successfully opened the box on their first attempts by using non-matching actions but matching techniques to those observed, suggesting emulation. In the subsequent test sessions, dominant observers consistently used the learned technique, whereas subordinates learned alternative techniques by explorative trial and error. Our findings demonstrate crows' capacity to learn by observing behaviours and the effect of dominance on transmission patterns of behavioural skills. Keywords: social learning; imitation; emulation; affordance; culture; innovation. (shrink)

「地獄に落ちても後悔しない」――親鸞が比叡山を捨ててまで求めた、法然の教えとは!? その教えと歩みを探った、著者渾身の一冊。.

日常においてはいつも素通りされている豊かな経験の世界がある―。“自明”であるがゆえに眼を向けられることのないこの経験の世界を現象学は精査し、われわれにとっての「現実」が成立する構造を明るみに出す。創始 者フッサール以来続く哲学的営為の核心にあるものは何か。そしていまだ汲みつくせないその可能性とは。本書は粘り強い思索の手触りとともに、読者を生と世界を見つけなおす新たな思考へと誘う。.

1960年代以後、日本の思想・哲学に大きな影響力をもった廣松渉(1933‐94)。この独自な哲学者の人と思想と時代と影響関係の全体を思想史上に位置づけ、その思考過程を精密に追跡した、気鋭の書。.

Early modern humans developed mental capabilities that were immeasurably greater than those of nonhuman primates. We see this in the rapid innovation in tool making, the development of complex language, and the creation of sophisticated art forms, none of which we find in our closest relatives. While we can readily observe the results of this high-order cognitive capacity, it is difficult to see how it could have developed. We take up the topic of cave art and archeoacoustics, particularly the discovery (...) that cave art is often closely connected to the acoustic properties of the cave chambers in which it is found. Apparently, early modern humans were able to detect the way sound reverberated in these chambers, and they painted artwork on surfaces that were acoustic “hot spots,” i.e., suitable for generating echoes. We argue that cave art is a form of cross-modality information transfer, in which acoustic signals are transformed into symbolic visual representations. This form of information transfer across modalities is an instance of how the symbolic mind of early modern humans was taking shape into concrete, externalized language. We also suggest that the earliest rock art found in Africa may constitute one of the first fossilized proxies for the expression of full-fledged human linguistic behavior. (shrink)

The phylogenetic position of the hagfish remains enigmatic. In contrast to molecular data that suggest monophyly of the cyclostomes, several morphological features imply a more ancestral state of this animal compared with the lampreys. To resolve this question requires an understanding of the embryology of the hagfish, especially of the neural crest. The early development of the hagfish has long remained a mystery. We collected a shallow‐water‐dwelling hagfish, Eptatretus burgeri, set up an aquarium tank designed to resemble its habitat, and (...) successfully obtained several embryos. By observing the histology and expression of genes known to play fundamental roles in the neural crest, we found that the hagfish crest develops as delaminating migratory cells, as in other vertebrates. We conclude that the delaminating neural crest is a vertebrate synapomorphy that seems to have appeared from the beginning of their evolutionary history, before the splitting away of the hagfish lineage. BioEssays 30:167–172, 2008. © 2008 Wiley Periodicals, Inc. (shrink)

Many functional glycoproteins are expressed on the lymphocyte cell surface. Some of them carry O-linked oligosaccharides (O-glycans), which are conjugated through serine or threonine residues. During various biological processes, including T-cell activation, a tetrasaccharide on the T-cell surface is dramatically converted to a branched hexasaccharide, called core2 O-glycan. The same structural change in O-glycans is also found on the lymphocytes from patients with immunodeficiency conditions such as Wiskott-Aldrich syndrome and AIDS. Several studies revealing the roles of core2 O-glycans in immune (...) responses show that this is a biologically significant change. In particular, core2 O-glycans expressed on the cell surface reduce cell–cell interactions, thereby regulating immune responses. Furthermore, core2 O-glycan is a key backbone structure in forming selectin ligands. Thus, O-linked oligosaccharides, in particular those containing core2 branches, play vital roles in immune responses and may play dual roles in certain situations. This review will summarize the results obtained from various studies investigating the roles of O-glycans in immunological processes. BioEssays 23:46–53, 2001. © 2001 John Wiley & Sons, Inc. (shrink)

Many functional glycoproteins are expressed on the lymphocyte cell surface. Some of them carry O-linked oligosaccharides (O-glycans), which are conjugated through serine or threonine residues. During various biological processes, including T-cell activation, a tetrasaccharide on the T-cell surface is dramatically converted to a branched hexasaccharide, called core2 O-glycan. The same structural change in O-glycans is also found on the lymphocytes from patients with immunodeficiency conditions such as Wiskott-Aldrich syndrome and AIDS. Several studies revealing the roles of core2 O-glycans in immune (...) responses show that this is a biologically significant change. In particular, core2 O-glycans expressed on the cell surface reduce cell–cell interactions, thereby regulating immune responses. Furthermore, core2 O-glycan is a key backbone structure in forming selectin ligands. Thus, O-linked oligosaccharides, in particular those containing core2 branches, play vital roles in immune responses and may play dual roles in certain situations. This review will summarize the results obtained from various studies investigating the roles of O-glycans in immunological processes. BioEssays 23:46–53, 2001. © 2001 John Wiley & Sons, Inc. (shrink)

「論理」と「合理性」は文化が作る。日・米・仏・イランの思考表現スタイルからその原理を読み解く。.

Pockett has drawn an alternative conclusion from the data of Libet, Alberts, Wright, and Feinstein , and suggested that it takes 80 ms, rather than 500 ms, for the sensation evoked by a stimulus to enter awareness. Here, I suggest that our conscious sensation evolves over time, during the period from 80 to 500 ms after a stimulus, until the sensation is stably localized in space.

Using artificially synthesized stimuli, previous research has shown that cotton-top tamarin monkeys easily learn simple AB grammar sequences, but not the more complex AnBn sequences that require hierarchical structure. Humans have no trouble learning AnBn combinations. A more recent study, using similar artificially created stimuli, showed that there is a neuroanatomical difference in the brain between these two kinds of arrays. While the simpler AB sequences recruit the frontal operculum, the AnBn array recruits the phylogenetically newer Broca’s area. We propose (...) that on close inspection, reported vocal repertoires of Old World Monkeys show that these nonhuman primates are capable of calls that have two items in them, but never more than two. These are simple AB sequences, as predicted by previous research. In addition, we suggest the two-item call cannot be the result of a combinatorial operation that we see in human language, where the recursive operation of Merge allows for a potentially infinite array of structures. In our view, the two-item calls of nonhuman primates result from a dual-compartment frame into which each of the calls can fit without having to be combined by an operation such as Merge. (shrink)

We revisit the EPR problem and make clear what is a correct comprehension of its problem. When one applies the quantum mechanics correctly, it will be shown that there is no paradox. According to these lines of thought, a quantum teleportation scheme without resort to the von Neumann projection postulate is presented.