高齢者介護の進化遺伝学（Evolutionary genetics of elderly caring）
Don't forget who you were at the age of 20! Originally, I intended to conduct this research on elderly care under the guidance of Professor Hirosuke Kawanishi, who had supported me through his Sociology lecture and Social Research Seminar when I was enrolled in the general education course at Chiba University. However, I later learned that he had already passed away, and sadly realized that such a valuable opportunity had been lost. The reports written by my seniors and classmates in his Social...
Since the paper deals with the evolutionary genetics of elderly care, I felt that I had no choice but to submit it to a genetics journal. Therefore, I decided to submit it to the overseas genetics journal to which I had previously submitted a paper. Up until then, I had written the manuscript in Japanese, but I ended up rewriting it in English, struggling with words I had never used before. Nevertheless, I managed to have it accepted, and it became my first paper on elderly care. I would like...
I recall that the society stated in its submission guidelines—or somewhere similar—that it welcomed submissions from a wide range of related fields. I also received an email from the editorial office indicating that they would review my manuscript, so I submitted it and looked forward to the results. Regrettably, to be candid, I think it would be fair to say that my correspondence was effectively ignored. Even during my email exchanges with the editorial office, I had the impression that my...
Deciding where to submit I recall that in 2016, while working part-time at the overnight day-service center and the short-stay facility, I resolved to publish a paper based on the research I had accumulated up to that time. Although I have mentioned this many times before, I was attempting to examine the sociological issue of elderly care from the perspective of evolutionary genetics, as a question that also relates to human nature. Because of this, I did not expect that anyone would understand...
Regarding the evolutionary genetic models employed here, as mentioned in earlier posts, they are derived from the population dynamics model that I studied at Edinburgh and previously applied to analyze fluctuations in genetic variation associated with insecticide resistance. In the present context, I have extended this framework to a human population in decline—such as the Japanese population, which is experiencing both a falling birthrate and population aging. For further details, please see...
Since elderly care involves close interactions between different age groups within families—such as parents and children, or grandparents and parents—and is inevitably tied to age relationships among family members, I thought that the evolutionary genetic models I would use should incorporate the age structure of the population. Therefore, I used the theory of kin selection in age-structured populations, as detailed in a paper authored by the professor who had supervised me at Edinburgh, to...
Evolutionary genetic models of elderly care As mentioned earlier, when considering the phenomenon and behavior of caring for elderly parents, one important question is whether forming a strong bond with one’s parents during infancy—strong enough to motivate caring for them in later life even at substantial personal cost—can be beneficial from an evolutionary genetic perspective. In other words, can such behavior increase in frequency within a population? Then, how should this be...
Thus, from the moment we are born, we begin to form strong emotional bonds with our parents, known as attachment, which draw us close to specific others—especially our parents. Because infants cannot survive without care from others, a genetic tendency to develop secure attachments to caregivers, particularly parents, would likely have increased infant survival in ancient environments where predators roamed. This type of attachment between parents and children is generally thought to persist...
Then where can we find the benefits of the parent–child relationship that outweigh the enormous costs of caring for the elderly? I believe the first thing to consider is the relationship between infants and their parents. This is because, as newborns, we humans are born completely helpless—unable to walk, let alone feed ourselves—and during our infancy and toddler years, we are utterly dependent beings who cannot survive without the help of others, especially our parents. Therefore, when...
Looking at parent–child relationships from an evolutionary genetic perspective I have been exploring this seemingly contradictory gap between Hamilton’s evolutionary theory and the actual human behavior of elderly care, from the standpoint of evolutionary genetics, which I have studied. For example, when a trait that appears to impose a substantial survival cost—such as the ornamental feathers of male peacocks—is maintained within a population, it is assumed that the trait provides some...