Is Aging an Accident of Evolution? Stanford Scientists Say "Yes"

[Swede]

The scientists used microarrays—silicon chips that detect changes in gene expression—to hunt for genes that were turned on differently in young and old worms. They found hundreds of age-regulated genes switched on and off by a single transcription factor called elt-3, which becomes more abundant with age. Two other transcription factors that regulate elt-3 also changed with age.

To see whether these signal molecules were part of a wear-and-tear aging mechanism, the researchers exposed worms to stresses thought to cause aging, such as heat (a known stressor for nematode worms), free-radical oxidation, radiation and disease. But none of the stressors affected the genes that make the worms get old.

So it looked as though worm aging wasn’t a storm of chemical damage. Instead, Kim said, key regulatory pathways optimized for youth have drifted off track in older animals. Natural selection can’t fix problems that arise late in the animals’ life spans, so the genetic pathways for aging become entrenched by mistake. Kim’s team refers to this slide as “developmental drift.”


http://www.dailygalaxy.com/my_weblog/2008/07/is-aging-an-acc.html

[Taverner]

1. Not really - its just a really formidible task for adaptation to accomplish

[Selatius]

2. I wonder if the results can be extrapolated to mammals including humans?

[DCKit]

3. It's thought that many ancient animals didn't die of "old age", but...

kept growing larger and larger until something else, generally injury, infection, cancer, etc..., killed them.

[Selatius]

4. You talking about huge creatures like dinosaurs? What since then changed in the environment?

Regardless, I figure if we could repair the damage done to DNA over the lifespan of a creature, you could extend life and youth for a very long time, perhaps indefinitely. A limited form of immortality, essentially.

[DCKit]

5. What you said - an inability to repair the DNA. n/t

[TZ]

6. Not a surprise

This has been theorized for awhile..that once an individual gets past the age of reproduction the genes don't function as efficiently..they kind of work intensely to get replicates of them passed on and then once they can no longer do so, tend to "wear out" so to speak.

[supernova]

7. So, we don't get old so much as drift away?