[bayesianhorse]

Well, preventing Cancer has been a priority for evolution since the first multicellular organisms arose. It's just not that easy.

Developing a drug is an economically difficult thing: Spend billions for the chance to win billions. The only alternatives to big pharma in developing these drugs are big government and big charity (Gates' Foundation et al).

[crusso]

Well, preventing Cancer has been a priority for evolution since the first multicellular organisms arose

It's only a "priority for evolution" to prevent cancer before the better years for breeding have passed - and evolution has done a fairly good job with that. After breeding and a little time for rearing young in the higher life forms, evolution has no real use for us.

[bayesianhorse]

Multicellular organisms have to control the replication and renewal of their cells constantly. In a simplified view, cancer is a loss of that control.

[sokoloff]

Preventing cancer that prevents reproduction or hampers offspring survival is a priority for evolution.

Cancer affecting the old is not strongly de-selected for by evolution.

[bayesianhorse]

There is no cancer which affects "the old" predominantly. The chances stay pretty much the same (with some exceptions). Also, at some age beyond 60, cancer stops being the main medical cause of death, being replaced by infections.

I also don't subscribe to the theory that individuals have to procreate to boost the survival of their genes. In reality it's a bit more complex than that, and even very old people can and do contribute to the survival of their children or their close relatives.

[kartan]

> In reality it's a bit more complex than that, and even very old people can and do contribute to the survival of their children or their close relatives. That's true for human beings. But for most species that is not true. Maybe that's why we are better at longevity than other species (http://www.medcan.com/articles/a_finite_number_of_heart_beat...). But we still have millions of years of evolution that say that it is better to be able to live short and intense than to be able to live long and die before achieving that of disease, predators, etc. Why nature will invest in an extreme long lifespan that is not going to happen? So for most species what happens to you as you grow old is not very important and other traits will be selected before lifespan by evolution.

[bayesianhorse]

I would not subscribe to the statement about what "the evolution says". Evolution does not produce the "best" individuals, it just drives population towards a local maximum in their particular environment, from their particular starting point. And that may mean a long life span or a short life span.