It never occurred to me that cancer could be a natural default condition that is suppressed in multicellular life but that is what Paul Davies and Charles Lineweaver are suggesting.

Briefly: Normal cells will divide a number of times and then die. This programmed cell death is called apoptosis. Cancer cells are cells that wont die. Early eurkaryotic cells had no use for apoptosis. That was a development of multicellular life. Failure of apoptosis may be a reversion to the earlier state. IOW cancer is built into the genes.

www.iop.org/news/13/jul/page_60392.html

I heard more than half the cancers are contagious and caught from other people !

Cancer per se is not contagious but possibly contagious conditions can cause cancer.

Contrary wise some other diseases can stop cancer.

Wouldn't the "development" of apoptosis by evolution look a little silly in the light of it not always working?
Yes we "developed" eyes and skin and whatever (apparently) and some people's doesn't work quite right. But it is not like a large nuber of people have no eyes, or their skin falls off. If cancer affects soemething like 20% of us then either it is unrelated to apoptosis failure or we didn't "develop" such characteristcs thru evolution.

I can't see one can have it both ways.

I'm not sure what you mean Mark. For evolution to work you only have to survive long enough to procreate. Then you pass your genes on warts and all. Cancers are reasonably rare amongst the young but far more common among the aged.

Stumbled on this lecture by Paul Davies on the very topic. It's a bit long but it's good stuff.

?t=2m50s

I'm out.....
What's my alternate forum these days?? Sailing or windsurfing......... May come back tomorrow fresh minded......

I just hope some day 'cancer' becomes a banned word within my life time...