Acquisition of linguistic and cognitive skills in chimpanzees and the social transfer across generations

本研究旨在阐明黑猩猩在实验室和野外的语言和认知功能，重点研究获得技能的机制和个体之间的社会迁移，特别是世代之间的迁移。我们研究了工具的使用，特别是石器在野外的使用，并探索了在实验室中展示的以下认知技能：理解人类言语和手势符号，获得人工语言的视觉符号，数字的理解和使用，包括生物运动主题的视觉信息处理，视觉搜索范式中提取特征的机制，自然概念的建立，符号的理解和使用，视频图像的连续识别等。实验室工作和实地工作的目的是阐明在每个个人层面上已获得的认知技能的社会传播。如何从一个…转移知识和技能比其他人更有个性吗？在非洲的实地工作侧重于工具的使用，特别是石器的使用，以及基于纵向研究的发展进程。结果表明，在3.5岁至5岁的年龄段内，儿童掌握这项技能有一段“关键期”。幼年黑猩猩花了9到10年的时间才达到成年黑猩猩的精致水平。以下几点可以为模范技能向学徒的社会传递提供重要的代际传递依据，如：“学徒仔细而长期的观察”，“学徒模仿的强烈动机”，“模范对学徒的社会容忍度”，“模范不积极传授，但表现出良好的模范行为”等。对黑猩猩进行面对面模仿的研究表明，黑猩猩很难在没有物体的情况下模仿简单的运动模式。这与模仿涉及物体的动作相对容易这一事实形成对比。对黑猩猩模型学徒实验的研究发现，学徒黑猩猩在第一次尝试之前和自己失败后立即去观察模型黑猩猩的情况有两次。为了进一步研究认知技能在母婴间的垂直传递，我们对三只黑猩猩进行了人工授精。除了上述对黑猩猩的研究外，我们还对猩猩、长臂猿和猕猴进行了比较研究。研究结果已发表在包括《自然》在内的主要期刊上。较少

The present study aimed to clarify the linguistic and cognitive functions in chimpanzees both in the laboratory and in the wild, focusing on the mechanism of acquiring the skills and the social transfer among individuals especially across generations. We studied the tool use, especially stone-tool use in the wild, and also explored the following cognitive skills shown in the laboratory : Comprehension of human speech and gestural signs, acquisition of visual symbols for the artificial language, comprehension and use of number, visual information processing including the topics of biological motion, the mechanism of extracting features in visual search paradigm, establishment of natural concepts, comprehension and use of tokens, serial recognition of video images, and so forth. The laboratory works and the field works aimed to clarify the social propagation of the cognitive skills that have been acquired in each individual level. How the knowledge and skills can be transferred from one … More individual to the others? The field work in Africa focused on the tool use especially stone-tool use and the developmental process based on the longitudinal study. It proved that there was a "critical period" at the age of 3.5 to 5 years old for the acquisition of the skills. It took 9 to 10 years for the young chimpanzees to reach to the refined level of the adults. The following points may provide important basis for the social transmission of the skills from the model to the apprentice across generation ; "careful and long-term observation by the apprentice", "the strong motivation to imitate by the apprentice", "social tolerance of the model toward the apprentice", "No active teaching by the model but showing the good model behavior", etc. The laboratory works proved the following points. The study of imitation in a face to face situation revealed that the imitation of simple motor pattern without objects was difficult for the chimpanzees. This contrasted the fact that the imitation of the action involving the objects was relatively easier. The study of chimpanzee model-apprentice experiments revealed that an apprentice chimpanzee went to observe the model chimpanzee in the following two occasions, before doing the first attempt and right after his/her own failure. For the future study of the vertical transmission of the cognitive skills between the mothers and the infants, we carried out the artificial insemination to have three chimpanzees pregnant. In addition to the above described studies on chimpanzees, we did the comparative studies on orangutans, gibbons, and macaques. The results have been published in the leading journals including "Nature". Less