Learning from Ageless Animals:
An Interview with John Guerin
By David Jay Brown
John Guerin is the founder and director of the AgelessAnimals Project–also known as the Centenarian Species and Rockfish Project. This long-range research project involves investigators at fourteen universities around the world who study animals that don’t seem to age.
There are certain species of rockfish, whales, turtles, and other animals that are known to live for over two hundred years without showing any signs of aging–a phenomenon known to biogerontologists as “negligible senescence.” No one knows for sure how long these animals can live, but to date there have not been any observed increase in mortality or any decrease in reproductive capacity due to age. Striking examples are a 109 year old female rockfish that was captured in the wild while swimming around with fertilized eggs, and a hundred-plus year old male whale that was harpooned while it was having sex. The purpose of the AgelessAnimals Project is to understand why these animals don’t seem to age and then to apply that understanding to human longevity.
Guerin is an experienced project manager, who conceived of the AgelessAnimals project and orchestrates all of the studies. The two principal advisors to this project are Dr. Leonard Hayflick and Dr. Aubrey de Grey, both of whom were also interviewed for the Mavericks of Medicine collection. Dr. Hayflick, discoverer of the “Hayflick limit” of cellular senescence, states that “Guerin’s project is not only unique, but probes an area of almost total neglect in biogerontology, yet an area with more promise to deliver valuable data than, perhaps, any other.”
When I asked Dr. de Grey about the importance of studying ageless animals he said, “All organisms with organs that rely on the indefinite survival of individual non-dividing cells (such as neurons in the brain) should age, though some, including humans, age very slowly. Some species do even better–we cannot yet measure their rate of aging at all–and studying them may well reveal ways to slow our own aging.”
In addition to coordinating and orchestrating the AgelessAnimals project, Guerin lectures regularly on the subject of ageless animals. To find out more about Guerin’s work and the AgelessAnimals Project visit their Web site: www.agelessanimals.org.
I interviewed John Guerin on March 14, 2005. John seemed eager and excited to discuss his project with me. We spoke about some of the latest research that’s going on with long-lived animals, why this type of research has been neglected for so long, and how studying ageless animals might help us to understand the aging process better and extend the human lifespan.
David: What inspired the AgelessAnimals Project?
John: Back in 1995 I began looking into biotech, biogerontology, and the studies of aging. I read many different books, articles, and scientific papers. The turning point came when I read Dr. Leonard Hayflick’s book How and Why We Age. Dr. Hayflick had a chapter called “Some Animals Age, Some Do Not,” and I thought, Wow, now that’s interesting. I’d heard rumors and old wive’s tales about how some animals live for an extraordinarily long time, but this was the first time that I had come across that information from a scientific source. So I started researching the literature on long-lived animals, and I found out that there’s very little known. On my Web site I have some references on what I found.
I met Dr. Hayflick at a Gerontological Society of America meeting in November of ‘95, and I told him about my project management background. I said, I’d like to join whoever is working in this area, and I asked him who is. His answer was, “Nobody is, but they should be.” So I tried to get something going on my own. I did a lot of research on different animals. I spent about a year looking at koi–the fancy Japanese carp–and it’s very likely that they do live quite a long time, at least over fifty years. They were reputed to live over two hundred years, but the readings were based on scales, and those are not accurate. So they didn’t turn out to be a good candidate to study.
Then in 1997 I got some data from the Alaska Fish and Game. There’s a chart at the bottom of my Web page with a rockfish on it that shows ages for different rockfish that were caught off the coast of Alaska, and the range is between twelve and 107 years. Now, that’s a randomly caught sampling–it wasn’t like they were trying to get older individuals. Those were the ones that fishermen caught and were going to people’s dinner tables that evening. So when I realized that individuals at those ages were available I became very interested. We got samples from the Alaska Fish and Game in 1997. I say “we” because by then I had a couple of researchers at Oregon State University, including the Linus Pauling Institute interested in looking at the rockfish. So the Alaska Fish and Game sent us five older rockfish. After we got the aging results, it turned out that the the youngest rockfish that they sent us was 79 years old, and the oldest was a 109 year old female that still had eggs.
David: That’s extraordinary.
John: Yeah, and kind of sad. How long would this fish have lived if it wasn’t caught? It didn’t die of old age. It was fertile and still going strong in the ocean at 109 when they caught it. So that helped us to focus the project on rockfish. We have had one study on turtles. Whales are a very fascinating subject too, because they’re warm-blooded mammals like we are, and they’ve now been documented to live over two hundred years of age.
David: How does one determine the age of these animals?
John: The most common technique for aging rockfish is the analysis of annual growth rings in the otolith, or ear bone. Basically, rockfish have incremental growth, so under a microscope their growth rings can be counted. There has been independent validation of this, and two recent international symposia have focused entirely on the importance of otolith measurement in fish life history studies. In turtles, the determination of minimum age is relatively straightforward, using tag and recapture methods. Dr. Jeffrey Bada at UC San Diego Scripps did the aging analysis for the whale study. For this study the whales’ ages were determined by using the aspartic acid racemization technique. In this technique, age is estimated based on intrinsic changes in the isomeric forms of aspartic acid in the eye lens nucleus. The references for these studies are on my Web site.
David: What is the goal of the Ageless Animals Project?
John: Quite simply, the goal is to understand the genetic and biochemical processes that long-lived animals use to retard aging. These long-lived animals have what’s technically called “negligible senescence,” as defined by Caleb Finch at the University of Southern California in Longevity, Senescence, and the Genome (1995).
David: What is negligible senescence?
John: Basically, this refers to an animal species that doesn’t show any significant signs of aging as it grows older. Unlike humans and mammals other than whales, there’s no decrease in reproduction after maturity. There’s also no notable increase in mortality rate with age, but that’s a little harder to prove. I’ve been talking with a statistician and he’s asking, how do you know? To do a study of this type would take a couple of hundred years to complete. But compared to us there’s no noted increase in mortality rate. I mean, if you are ninety years old, you’re much more likely to die next year then you are if you’re only twenty years old. But we don’t seem to see any increase in mortality with rockfish and several of these other animals over time.
David: Why do you think these animals can live for so long without showing any signs of aging?
John: The purpose of the project is to understand why, and how to apply it to extending the healthy lifespan of humans. My background is in business project management; I have a project management professional certification. I’m not a bioresearcher, a biochemist, or a biogerontologist–but I’m the one who organizes it all, and gets everyone involved. I get the researchers the samples and all that.
Actually, I thought I had a better idea about why these animals have negligible senescence when I started this project ten years ago. But it’s hard to say. Back then we didn’t know whales lived that long. That whales can live for over two hundred years was just discovered in the last five years. Up until then we thought that humans lived longer than any other mammal. So why certain animals would live much longer than others, and much longer than we do as a matter of fact–pretty much double what we’ve known humans to live–we don’t understand.
There are some people who think that this can’t be so, that this would violate the evolutionary theory of senescence, because nature doesn’t select for longevity. But that’s not necessarily true, because what’s commonly seen is that there’s just such a high mortality rate in nature. Even for humans, probably before two thousand years ago, we didn’t live very long. We were hunted by tigers and wild animals, and traits of longevity, presumably, weren’t selected for. But if these animals, like the rockfish, can be 109 years old and still be reproductive, nature is going to allow those genes to keep contributing to the gene pool, so that