On April 23, 2021, the third lecture in the Academic Frontier series was held online. The lecturer was Kunihiro Ota (太田邦史), a professor at the University of Tokyo’s Graduate School of Arts and Sciences, specializing in molecular biology and genetics. The lecture was titled “What Will Life and Humankind on Earth Be Like in Thirty Years’ Time?” It was intended to reflect upon our past, present, and future in terms of evolution and biodiversity.
We all know that humankind has had a tremendous impact historically on the planet’s environment, but Ota argues that we should comprehend the seriousness of this from the viewpoint of biodiversity. Though the decline in biodiversity has several causes, one of the most important is the domestication of animals and plants. To see it in terms of numbers, the total vertebrate mass (weight) on the ground is now 32 percent human, 67 percent livestock, and just 1 percent wildlife, while wildlife accounted for 99 percent ten thousand years ago. Biodiversity is essential for life on Earth because it enables life to overcome and even take advantage of environmental change. If genetic diversity is maintained, populations with outlier genetic traits may adapt to the environment and new species can emerge, even after great environmental changes. Earth has experienced several mass extinction events, such as large-scale volcanic activities and meteorite impacts, but they led to a subsequent increase in the number of species. Life maintains its robustness by creating “waste.” Humankind has degraded this robustness by domestication and other activities, including improvement of transportation, which results in homogenization of habitats. This whole process has made life vulnerable to environmental change.
A lively discussion with the floor followed the lecture. The core notion Ota presented in the discussion was that life comprises networks. In other words, life is interdependent. No species lives independently but is dependent upon other species, which themselves depend on yet more species. Humans are no exception. We have been dependent on many forms of life and will be so forever. This life network is robust because of the diversity of its nodes. Human society has never transcended the network of life but simply changed its form, and the way we live in the network is not sustainable because we have diminished its diversity—something even more apparent in the present. To pursue sustainability, we must reflect upon this interdependency of life and refrain from exceeding the limit of nature’s self-restorative potential. Such reflection implies rethinking our well-being.
The lecture not only gave us a biological perspective on society thirty years from now but also suggestions about how we should set the timescale for rethinking our existence and what kind of reflection is needed. Thirty years is an extremely short period in biological history. However, we humans live according to both human and biological timescales, and thirty years may be sufficient to reflect upon the condition of our existence in the biological timescale and construct ways to coexist harmoniously with other species on Earth. In this sense, the lecture seemed to give us a fundamental task that we must all tackle.

Reported by Akihiro Miyata (EAA Research Assistant)