<h3>Why? Elephants don&#8217;t get cancer and they also don&#8217;t age.</h3>
Humans inevitably age. As we grow older, we become susceptible to illnesses and worry about cognitive decline. Cancer is a particularly concerning issue. Statistics show that one in two Japanese individuals will develop cancer, with one in four men and one in six women succumbing to the disease. Many people aspire to remain healthy until their last breath, aiming for a vigorous and lively existence.
&#8220;Elephants achieve this ideal. Despite some living for over 60 years, these creatures, with their immense size and numerous cells, remarkably do not develop cancer. They exhibit no signs of aging, often walking tens of kilometers with their companions until their final moments,&#8221; 
Explained by Takehiko Kobayashi, author of &#8220;Why Do Only Humans Age?&#8221; and professor at the Institute of Quantitative Biology, University of Tokyo.
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<figure id="attachment_365704" class="wp-caption alignnone" style="width: 5402px;" aria-describedby="caption-attachment-365704"><a href="#" data-ident_hash="7599c87c"><img src="https://res.cloudinary.com/fridaydigital/image/private/t_article_image/wpmedia/2024/03/05535b70e97daa3dffa4ccab3b9faaad.jpg" alt=""></a><figcaption id="caption-attachment-365704" class="wp-caption-text">Professor Kobayashi is currently conducting research aimed at preventing genetic damage. &#8220;If successful, this research could eliminate the fear of cancer and dementia,&#8221; says Takashi Mori.</figcaption></figure>
According to Professor Kobayashi, the reason for cancer and dementia is that as DNA gradually breaks down with age, cells age. However, elephants do not develop cancer because they possess a gene called LIF6 in addition to p53.
&#8220;P53 functions to eliminate aging cells, and LIF6 is a gene that assists in p53&#8217;s function. Cancer arises from DNA damage, but elephants excel in killing and eliminating damaged cells.
Since aging and damaged cells are also eliminated, elephants do not show signs of aging and can walk tens of kilometers with their companions until just before death. They often die due to circulatory system issues such as myocardial infarction.&#8221;
It&#8217;s quite enviable. However, LIF6 is a gene unique to elephants and not found in humans. Research is currently being conducted on what would happen if LIF6 were introduced into humans, but there is still no clear progress.
<h3>The wisdom, knowledge, and altruism of elderly humans have contributed to making humanity a strong community.</h3>
Most wild animals die when they lose their reproductive ability. Why do humans live for decades even after losing their reproductive ability? Is it because of advances in medicine?
&#8220;It&#8217;s not solely due to medical progress that lifespans have increased. While medical care is necessary when one falls ill, what&#8217;s even more crucial is nutrition and public health.
Recent increases in lifespan are largely attributed to improvements in nutrition and public health, resulting in enhanced immunity and decreased prevalence of infectious diseases due to abundant food and cleaner living environments. However, even before that, the presence of elderly individuals within a population was advantageous.&#8221;
Human history spans back 7 million years. Considering that lifespan has gradually extended since then, it&#8217;s plausible that medicine may not be the sole factor.
&#8220;Humanity emerged from forests and opted for a communal lifestyle on flat terrain 7 million years ago. Throughout history, communities with elderly individuals have thrived. This is because the elderly accumulate various experiences, knowledge, skills, and wisdom, and possess the ability to lead and unify the group.&#8221;
In youth, there&#8217;s energy for challenges and competition, leading to a lifestyle characterized by ambition and competition. As energy diminishes with age, perspectives broaden, and individuals tend towards a cooperative and communal lifestyle, desiring to contribute to various aspects of society.
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<div data-friday-nextpage-lead="Japan's mandatory retirement age is a drain on human resources and intellectual property."></div>
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Professor Kobayashi suggests that the knowledge, skills, experience, and altruism accumulated over a lifetime, as well as the ability to unify communities, played crucial roles in stabilizing societies and became essential elements in educating children. The decline in eyesight, physical strength, and other faculties in old age may also be necessary for the shift from selfishness to altruism.
&#8220;If elderly individuals were not valuable to society, lifespans would not have extended. In fact, even among chimpanzees, rarely do individuals exceed the age of 50. Aged chimpanzees were likely not deemed essential within chimpanzee societies.&#8221;
 
<h3>The mandatory retirement system in Japan leads to the outflow of talent and intellectual property.</h3>
The reason why humans have become long-lived is because older individuals historically made significant contributions to society. Although there is the term &#8220;elderly nuisance,&#8221; it refers only to a portion of older individuals. It&#8217;s dangerous to lump all elderly individuals together and bash them, especially in a country like Japan, which is experiencing rapid aging. If society sees the elderly as a burden, there is no future.
“Experienced and balanced seniors are valuable resources in today&#8217;s Japan. A societal system that leverages seniors is necessary.”
To achieve this, discrimination based on age, such as mandatory retirement, should be stopped. Age-based restrictions stemming from mandatory retirement affect not only seniors but also younger individuals.
“For instance, with a retirement age of 65, a 60-year-old may be unable to change jobs. In academic research, once researchers reach 60, they may not be able to mentor new graduate students until they obtain a degree, leading to a decrease in enrollment. 
Some researchers even move abroad where there is no mandatory retirement, resulting in a drain of talent and intellectual property. It&#8217;s all negative.”
While one is healthy, it&#8217;s better to work, Professor Kobayashi says.
&#8220;Why don&#8217;t some people want to work? It&#8217;s because they lack fulfillment in their jobs. For such individuals, there should be opportunities for career changes. If the job is enjoyable and fulfilling, one can continue working. Mandatory retirement acts as a barrier to career changes and should be abolished as soon as possible.&#8221;
With aging populations and declining birth rates becoming critical issues, Professor Kobayashi suggests that humans may adopt an insect-like lifestyle in the future.
&#8220;Bees and ants have queens that reproduce while worker bees and worker ants support them. When trying to maintain the species as a collective, bees and ants specialize. Humans may start making similar choices.&#8221;
A society where individuals who have children are thoroughly supported is becoming a reality in some aspects.
Humans have chosen to age to survive. What path will they choose in the future?
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<figure id="attachment_365705" class="wp-caption alignnone" style="width: 600px;" aria-describedby="caption-attachment-365705"><a href="#" data-ident_hash="4266cac5"><img src="https://res.cloudinary.com/fridaydigital/image/private/t_article_image/wpmedia/2024/03/f210b558ae14f5b8edfb2249d70a01d2.jpg" alt=""></a><figcaption id="caption-attachment-365705" class="wp-caption-text">Why Only Humans Age&#8221; (Kodansha Gendai Shinsho)</figcaption></figure>
Takehiko Kobayashi, Professor at the University of Tokyo&#8217;s Institute of Quantitative Biology, researches the mechanisms of genome regeneration (rejuvenation), as well as the mechanisms of cell aging and cancer caused by the malfunction of genome regeneration mechanisms. His authored works include &#8220;Why is Life Span Determined?&#8221; (Iwanami Junior New Book), &#8220;98% of DNA is a Mystery&#8221; (Kodansha Bluebacks), &#8220;Why Do Living Things Die?&#8221; and &#8220;Why Do Only Humans Age?&#8221; (all from Kodansha Contemporary New Book series).

 Izumi Nakagawa

 Most wild animals lose their reproductive capacity and their life span ends. Why do only humans live for decades after losing the ability to reproduce? We asked Takehiko Kobayashi, professor at the University of Tokyo's Institute for Quantitative Biosciences, author of "Why Do Only Humans Age?

Could Humanity Embrace an Insect-Like Lifestyle? Tokyo University Professor Explores Aging and Its Potential Universality

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