Comment by podocarp
9 hours ago
You can't justify it being OK just because it's common. Here, this just makes benchmarks into a low signal and useless marketing number once people get numb to all the 99%s.
Also no idea what viruses and cancers have to do with this. Cancer is surely very poor reproductively because they never spread to other hosts.
Cancer is simply cells breaking free of the cooperative jail. Essentially the grey goo scenario of nano machines. Instead of cooperation they just do their own thing.
Cells have a certain optimised DNA mutation rate kept in check by various machinery. Multi cellular life expects each of these little replication machine to co-operate in the grand scheme of running a body. But it's also required in the grand scheme for DNA to mutate a little bit to ensure population variance. So you could say that cancer is the tax paid for having cooperative yet flexible and adaptive nano machinery.
So yes the propensity for cancer developed under evolutioniary pressure towards a non zero level.
The population could have optimised for zero cancer but it would not have paid for itself in terms of overall population adaptability and survival.