Whale Longevity as an Exemplar
Here is an interesting scan of an old article on whale life span that I hadn't noticed until now (it was mentioned in an article at Lew Rockwell that touched on healthy life extension - a rather surprising sign of the way in which our ideas are spreading).
In studies that could rewrite biology textbooks and establish whales as the longest-lived mammals on Earth, scientists in Alaska and at the Scripps Institution of Oceanography in La Jolla have estimated the ages of three bowhead whales killed by Inupiat Eskimos in northern Alaska at 135 to 172 years. At the time is was killed, a fourth bowhead whale was believed to be a stunning 211 years old, the researchers concluded.
Age was estimated by looking at chemical traces in the eyes and ivory harpoon tips from a century or more ago embedded in the whales. Fascinating stuff. I've mentioned the Ageless Animals website before at the Longevity Meme; the scientific findings reported there form a good rebuttal to some objections to healthy life extension. Many of these very long-lived animals are not so different, biochemically speaking, from us humans. If animals can live such very long lives, then it's certainly within the realm of possibility to develop therapies to greatly extend human healthy life spans.
"Many of these very long-lived animals are not so different, biochemically speaking, from us humans. If animals can live such very long lives, then it's certainly within the realm of possibility to develop therapies to greatly extend human healthy life spans."- Reason
Indeed, and not only that but they've even FAR FAR more cells than us humans. Yet they manage to keep 'em in check for such long periods of time.
you're site's focus on 'life-extension' ignores what every insurance man knows---to survive 'accidental-death' on Earth is quite unlikely by 'projected' age of 120 years---and we are not speaking of 'mass-extintions'---bio101---'the rule on Earth, not the exception'. industrial, automive,'slipping-in-the-tub', a host of other 'accidental' demises is how insurance cos. predict---so, you solve the riddle of the research lady's 'immortal' unicellular worms? and we have 300 years---who may survive this modern environment to full benefit?
attacking the 'human-span' problem is noteworthy, but useful only to those who choose to 'live in a vault', no defense from 'average-events' may be shown---so, any route of true 'longevity-on-earth' should incorporate insurance co. tables on 'accidental-demise'. then you will see my point. there is an underlying factor you miss---
life on planets is inherently dangerous.
There is a general tendency in biology, the bigger the mass of an animal, the longer its lifespan.
Or put it differently, the more cells it has, the less energy a cell receives per time unit and the longer it takes to exhaust it (assuming a fixed energy turnaround per cell per lifetime).
A nice example are bees, where queens and worker bees are genetically identical, however their difference in life expectancy is enormous (as is their difference in size).
As we cannot significantly increase our mass (guess nobody wants to be tranformed into a whale), I see only two ways to increase our maximum) lifespan:
1.) Calorie restriction, i.e. slowing down the exhaustion of our cells, which is quite limited to some percent of life extension and difficult to implement.
2.) Effectively increasing body mass by renewing cells (repairing them) or maybe better replacing them (e.g. stem cells).
My conclusion: To find a biochemical fix in the cell for extending lifespan is a lost case.
A calorie restriction mimetic will just do what calorie restriction does, it slows down metabolism in the cell.
Therefore we should concentrate on 2.).
Trying to repair cells the way it's intended with SENS is therefore one good ansatz, I think.