Could cybornithics be the next step in evolution?

[stephen_speicher]

"Average life span" is the description of the upper limit of years on earth that a healthy member of the human species can expect to get.

I must be reading the wrong books and journals. I have always understood "average life span" to be the average age that a member of a given population lived.

[stephen_speicher]

What is new, and what bio-tech will only reinforce, is an actual increase in the upper limit of years  that define the human life span.  If the secret of reversing cell death is acquired, then humans will face the prospect of some previously inconceivable long lives.

A biologist friend of mine works in the field of life extension, and there are many interesting discoveries being made. The field is, however, beset with a great deal of controversary among several competing approaches. Some seem more promising than others.

I read a paper a while ago which I found interesting, even though it does not purport to directly address today's research areas. The authors performed a broad study of the life expectancy of haplorhine primates (higher level -- humans, apes, monkeys, ...) and found a correlation between brain size and life expectancy. In particular, the cerebellum was the brain structure which correlated best with life expectancy.

Historically the cerebellum was thought to be a purely motor structure, but recent studies connect the cerebellum with language and other cognitive functions. (By "connect" I simply mean what imaging studies identify.) Interestingly, the cerebellum contains more neurons than any other individual subdivision of the brain. Magnetic resonance imaging studies have also shown that there is an age-dependent loss, approaching 30%, of parts of the structure. The speculation here is that dietary toxins may affect cerebellar mass and Purkijne cells, which might explain the abundance of cerebellar neurons to compensate. This is just pure speculation, and speculation based on correlations no less, but it would be quite wonderful if there was a regulatory mechanism here whose output would extend the whole life.

[Reason's Ember]

I must be reading the wrong books and journals. I have always understood "average life span" to be the average age that a member of a given population lived.

Yep, I conflated two distinctions myself--maximum life span and average life span--and then misidentified the latter with average life expectancy. I was unfortunately following someone else's error who claimed to be an expert in a recent issue of The New Republic, which while not a scholarly journal has the pretensions of being a "learned" one. It's bad enough to have made the mistake, worse to have done it in the context of supposedly correcting someone else.

I am by no means an expert, though I take an avid and current interest in this, because my main intellectual interest is in philosophical ethics. "Philosophical ethics" can be taken in the widest sense of forming basic principles that can answer the question, "how should one live?" Those principles will depend partly on an exacting understaning of just what a human being is or can be, so I am starting to read up on the relevant work in human biology, genetics, and anthropology.

I am trying to prepare a paper this summer that responds to some of the writings by Leonard Kass, who is the Chairman of the President's Bioethics Council. The Council recently put out a publication: "Beyond Therapy: Bioetechnology and the Pursuit of Happiness." Some of the papers are available here: http://www.bioethics.gov/topics/beyond_index.html.

My main point in the post above, which I do not want to get lost in all of this, was that we are on the cusp of a radically new possibility, which is what "amagi" has helped identify more clearly as the possibility of effecting "the basic rate of aging". I don't think this would have any direct effect or responsibility for putting a bottleneck on the material resources necessary for human survival on earth, for the reasons that Betty Speicher helped identify when she brought up Malthus' basic error (i.e., underestimating human ingenuity).

However, I do think it's possible and worthy of debate to discuss whether or not this increase in maximum life span would affect the conditions of human happiness and the structure of much practical reasoning related to it. Kass harps on this all the time, using his wonderful to education to quote Aristotle, Tolstoy, Dostoyevsky, and Shakespeare on the nature of the human condition. If, as Kass points out, Americans spend more money trying to fight baldness than the world does trying to fight malaria, then that's an interesting fact, but it does not show that contemporary Americans or Westerners are any shallower than any other politically constituted people. It definitely does not show that our interest in prolonging life is an essentially cosmetic one.

Thus, the point of my essay will most likely be that (1) these great humanists might have profound and valid things to say about the occasionally destructive form that a quest for a fountain of youth or immortality can take; (2) it is a very bad (not to mention very vague) reason to limit certain kinds of research because of what is commonly called "playing God." There may be other valid reasons to limit research on therapeutic cloning or stem cells, but the dangers of playing God is not one of them.

Edit: My favorite quip when confronted with the "playing God" charge in debate is to say "no, we are playing Prometheus, and it's the only game in town."

[stephen_speicher]

I am by no means an expert, though I take an avid and current interest in this, because my main intellectual interest is in philosophical ethics.  "Philosophical ethics" can be taken in the widest sense of forming basic principles that can answer the question, "how should one live?"

Well then, I have a real winner for you. I previously gushed over Tara Smith in another post -- she is one of my favorites among the newer-generation Objectivist intellectuals -- and one of her books is "Viable Values: A Study of Life as the Root and Reward of Morality," Rowman & Littlefield Publishers, Inc., 2000. I cannot think of a single book more suited to your purpose than this one. And, as I mentioned previously, Smith has such a fresh, unique style of presenting ideas that you will not even know you are reading Objectivism, until you are all done and see how much sense it all makes.