Many things in nature are self-governing. Hawaiian koa wood is now being raised on plantations (most of the forests were slashed and burned years ago to make grazing land for cattle), and after a decade or so, growers wondered why they only had rows of stumpy, sickly trees. Because more is always mo' bettah for humans, they planted the trees close together, only to learn that, like some other plant species, the koa tree's roots contain natural toxins that inhibit other trees—even other koas—from growing too close.
Maybe our toxin is our own insatiability. We're inventing our own demise. Consider organochlorines. According to Texas populist Jim Hightower's marvelous muckraking book There's Nothing in the Middle of the Road but Yellow Stripes and Dead Armadillos (HarperCollins, 1997), the 50 years in which chemical companies have dumped millions of tons of organochlorines into our biosphere has coincided with a 60 percent increase in breast cancers, a trifold increase in testicular cancer, and a 50 percent drop in the average man's sperm count. So maybe we won't double in population.
(Interestingly, on the breast cancer front, Hightower reports that the Zeneca Group chemical company makes billions as a leading producer of organochlorines alleged to cause breast cancer, while also funding the Breast Cancer Awareness Month organization, which curiously ignores studies implicating organochlorines, while Zeneca also makes nearly half a billion dollars per year marketing a marginally effective drug to treat the breast cancers they may be causing. Are they covering all the bases or what? Another side note: much of the organochlorine pollution is caused by paper mills. I hope you're as pleased as I am to know that the Weekly is printed on chlorine-free paper.)
The problem with all known cancer treatments is that they also take a toll on healthy cells. Whatever chemicals we whack ourselves out with—if all else fails, we've still got megatons of radiation treatment to fall back on —are also going to be-whack other critters great and small. Bad dirt!
Cancer is not a term I bandy about as some abstract notion. I've had it and don't recommend it. Friends have had cancer. My mom has. A year ago, I watched my dad die of it. I think we could find better things to emulate.