Japan is facing a potential future where all its citizens could share the same surname, Sato, by the year 2531 if the country's restrictive marriage laws remain unchanged. Currently, Japan legally mandates that married couples must adopt the same surname, typically the husband's, with same-sex marriages still not recognized.
A recent study led by economist Hiroshi Yoshida from Tohoku University in Sendai highlighted the concerning trend. The most common surnames in Japan, such as Sato, Suzuki, and Takahashi, are becoming increasingly prevalent, with Sato alone being held by 1.8 million individuals out of a population of 125 million.
The 'Think Name Project,' advocating for legal reforms to allow couples to retain their original surnames, commissioned Yoshida's study. However, the projection of a universal surname could be altered by Japan's declining marriage rate, which saw a nearly 6% decrease in 2023, falling below 500,000 marriages for the first time in 90 years.
Yoshida emphasized that the calculation could change significantly if marriage rates continue to plummet. Moreover, Japan is grappling with a rapidly aging population and a declining birth rate, with the proportion of elderly individuals aged 65 and above reaching a record high of 29.1%.
Prime Minister Fumio Kishida has warned about the impending population crisis, as Japan's fertility rate stands at 1.3, well below the 2.1 needed for population stability. The country has experienced a consistent population decline since the 1980s economic boom, with deaths surpassing births for over a decade.
Across East Asia, including China, name diversity is limited, with a significant portion of the population sharing common surnames. In Japan, efforts to preserve surname diversity and address the potential extinction of names are gaining traction, reflecting broader concerns about the country's demographic challenges.
The study also highlighted the Galton-Watson process, a natural phenomenon in patrilineal societies where surnames diminish over generations as women typically adopt their husbands' surnames. Japan's evolving demographic landscape underscores the urgent need for policy reforms to address these complex societal issues.
