Why are manhole covers round?

I have been blessed and cursed by an analytical mind. The way I see it, there is a solution to every problem and an explanation to every mystery. We may not see it (yet) but the answer is there. As long as I can remember, my mind has churned at solving real problems as well as trivial pursuits.

The simple task of walking from my home office upstairs to the kitchen downstairs to get something to eat typically involves several billion calculations. First, wait for a time when my computer is busy doing something, don't want to waste spare cycles. Wait a sec, my daughter's field trip authorization form is right here too, but I don't have a pen. Should take the paper with me to sign or should I bring a pen back from the kitchen. Hmmm...where is her backpack? She'll need this form in the morning...I think it is near the front door...what makes the most sense and where should I sign it to be the most efficient. I need a beer too. Import or domestic? That dictates whether it will have a twist off cap or not, which means I may need to think about a bottle opener. Oh I think I left that in the garage last time I was working on a game. Crap, that is way out the way...does my daughter's backpack have a bottle opener on it? That'd be great. I know they make Reef sandals with a bottle opener on the bottom. What a great invention. I wonder if they have a patent on that? Let's Google that, but before I do, let's see why imported beers don't have twist off tops. Is that a law, federal or state? Wonder who invented the twist off top? Remember pull tabs? Those were replaced with the pop-tops we have today. I wonder if you really can buy a wheelchair by collecting a garbage bag of aluminum pop-tops? Let's go hit Snopes.com and find out. Look at that, turns out Thomas Crapper did not invent the flush toilet after all. Funny, in London, manhole covers have the name CRAPPER right on them. How ironic. I wonder why manhole covers are round? Turns out that is the only shape that makes it impossible for the cover to fall down the hole. That's pretty cool. See, there is an answer to everything. Much to Linda's chagrin, my mind never seems to figure out how to incorporate "there is a basket full of laundry here at the bottom of the stairs, maybe I should take it upstairs" into my equations. There may not be an answer for that one...LOL.

If you have a brain wired like mine, you know exactly what I'm talking about. If you don't, then you likely think I'm a bit crazy, and I'm not sure I can disagree. With that as the backdrop, I have been thinking a lot about cancer and 'why?'. Not 'why me?' or 'why us?' but 'why cancer?'. What role does cancer play in the big picture? I can't seem to wrap my head around it.

I can understand a virus. It is contagious, it moves from person to person, typically having a delayed onset of symptoms so that the current host is at least healthy long enough to spread the virus to the next host. I'm sure over that last billion years there have been virus variations that killed their host on contact. Guess what? Host 1 doesn't live long enough to spread to Host 2 and the virus doesn't get to spread its DNA (nature's prime directive). End of the line for that virus' lineage. Natural selection over millions of years makes sense. I can get my head around that.

So what about cancer? It is not a 'modern' disease. Although I'm sure pollutants and man-made environmental factors have increased the incidence of cancer and other disease, they are not the sole cause. Cancer predates man. It has been around for at least 100,000,000 years, as evidenced by recently discovered dinosaur fossils showing signs of cancerous bone tumors. I suspect it was around long before dinosaurs too. Unlike a virus or bacteria, cancer is not a foreign invader, it is home grown. It is our own cells and DNA gone awry. The Human Genome Project has mapped out our DNA and cancer researchers can point to certain genes and say, 'in some cases, this gene X suppresses cell activity Y but in cancer cells, this gene is defective and that, in combination with this protein over-expression Z yields a 34.7% chance of XYZ. That's very cool, but still doesn't explain the 'why'? Is it possible that cancer, like other genetic mutations, is simply part of natural selection and the evolutionary process? Some genetic mutations yield eyes on the front of the head for predators and eyes on the side of the head for prey, and natural selection dictates which traits go on to survive. That makes sense. Are those same genetic mutations responsible for cancer? Well, they've been there in some form for a long time so I have to assume they have some purpose. But what? I guess when we figure out the 'how' and 'why' we will have a cure. There is an answer and there is a cure, we just need to find it.