How do we study the evolution of the mind:The evolving methods （GAO Jie／2024）

第13 期 特定助教 （野生動物研究センター）　GAO Jie

　In this article, I would like to introduce several common and cutting-edge methods in the research of animal cognition with a bit of touch in the history of this field. I will include my own research as examples and discuss my current project in the end.

　There are many facets of the study of the evolution of the mind. This field is also called comparative cognition, because the fundamental logic behind it is to compare different species, link them with phylogenetic and environmental factors, and try to rebuild the evolutionary path of certain cognitive abilities. Before a more systematic research system was built in this field, many early studies have paved the way for the standardized methodology in the later phase. Many people are familiar with Pavlov’s dog experiment. He used a bell sound with feeding behavior, and later, the dog could produce saliva upon hearing the bell sound without seeing any food. This is called conditioning, a crucial technique used commonly in almost all animal related activities, including animal training, farming, and of course, animal experimental studies.

　In the last century, many researchers started to focus on non-human great apes, because they are the closest related to humans. How unique human languages are had also became a heated topic. Among the stories and anecdotes of many famous language project apes, such as Kanzi the bonobo, Koko the gorilla, Washoe the chimpanzee, and Ai the chimpanzee, one episode impressed my mind until now from the moment I read it. It’s chimpanzee Gua. Researcher Winthrop Niles Kellogg and his wife raised Gua at their home, with their infant son Donald. At first, they hoped Gua could learn to speak human languages in this foster environment, because it’s similar to a developing human baby’s environment where they could learn to speak. However, they found that instead of Gua learning to speak human languages, their son Donald started to “speak” like a chimpanzee, i.e., making chimpanzee vocalizations. This very engaging study strongly showed how good humans are at mimicking, and chimpanzees, on the other hand, are probably not, at least compared with humans.

　Some people may fantasize this kind of closeness with wild animals, but we gradually came to realize that it is not right to put wild animals together with humans. There are considerations in terms of safety, hygiene, and the effect on the development of the animals: they are supposed to be with their own social partners instead of humans （and perhaps, also the effect of the development of humans, like little Donald. Animals became experimental participants, and researchers are not supposed to live with them: we need to study them in a distance, using controlled scientific methods. With this study field growing and the development of various technology, fixed studying paradigms have been developed, and so are novel, cutting-edge ones.