There are species in nature that are able to regenerate themselves and live forever. These animals are able to achieve something humans have been searching for generations to attain.
Three U professors were featured in a panel discussion at The Leonardo museum on Friday. Part of the museum’s “After Hours” series, the discussion focused on the human obsession with immortality, death and aging.
Ray Kurzweil, an American inventor and futurist who recently became the director of engineering at Google, predicts computers will surpass the power of the human brain as early as 2045. Another theorist most popular with audience members and panelists alike, Aubrey de Grey, views aging as a disease to be cured.
Panelists also explored the technical aspects of aging. A key term in the discussion was senescence, the process by which cells and organisms gradually begin to degenerate and die. Telomeres shorten with each cell replication, and eventually the cell can no longer successfully copy its DNA. Without the telomeres, cells lose the end of their chromosomes, which carry vital information. Senescence occurs when cells lose this ability to divide. These extra, now useless, cells can cause serious damage. In other words, senescence is aging.
There are at least four species on the planet that do not age, at least not noticeably, the moderator said. This is called negligible senescence. In these organisms, age is not an issue and death rates do not increase with age as they do in most species. These organisms include sea squirt, hydra, coral and a certain type of jellyfish dubbed the immortal jellyfish.
“All of these species have two things in common,” the moderator said. “All of them live in the water. And all of them reproduce asexually. So that may be a price we’re not willing to pay.”
The immortal jellyfish ages naturally to adulthood and then reverts its cells back into their youthful state, repeating this process indefinitely. This makes the jellyfish immortal from a biological perspective, but this method may be unavailable to humans, who obviously lack this ability to absorb and transform our own cells.
Robert Marc, director of research at the Moran Eye Center, said this isn’t the only problem humans face in trying to gain immortality. Many futurists believe we will soon be able to upload our brains to a computer system and thus achieve virtual immortality, but Marc said it isn’t that simple.
“A brain is not a computer, and the brain does not work digitally,” he said. “It’s a common error to take the brain-computer metaphor literally. But there is no possibility that we can ever capture a brain computationally.”
Marc said it would take 163 zettabytes, or more than 1 billion terabytes, to store all of the information and connections in a human brain. At the current download speeds of which our technology is capable, that would take 5 million years to download.
The ethical issues involved with immortality also were addressed. Jeffrey Botkin, a professor of pediatrics and chief of the Division of Medical Ethics and Humanities, challenged the audience’s initial desires for immortality.
“There is a huge discrepancy between people who want to live forever and people who think that everyone should live forever,” he said. “So if we were to gain that technology, how would we choose who would get it?”
Richard Cawthon said the goal should not be living forever but simply living a quality life as long as possible.
“Your risk of dying doubles every eight years you are alive,” he said.
Cawthon, a research associate professor in the Department of Human Genetics known for his work with telomeres, explained that if it were possible to stop that exponential risk factor in its tracks at age 20, the average lifespan for a woman would be 1,500 years.
Considering testosterone levels and risky behavior, however, the average lifespan for men would only be 500.
Since we cannot yet halt that risk factor, though, senescence is an issue.
Marc said the best step a person can take to ensure a high quality of life is to protect his or her cognitive abilities. Exercise and sleep help, and maybe one day a portion of your mind will be available for download. But when it comes down to it, Marc said, “Wear a helmet.”