Our forebears may not always have known what caused the cycles, but they did know enough to look for patterns. "Grass has failed along the south slope, we won't have many mountain goats to hunt in two years." That they managed to observe such things and correlate them shouldn't come as a surprise, because that's how we survived, by being attuned to these kinds of cycles. I'd go as far as to say that our brains are hard-wired for correlating data, because it does this at its most efficiently when we meditate or sleep.
So when a friend of mine twenty years ago pointed out a seemingly amazing fact, I let it percolate in my subconscious for a while. The amazing fact is that, as a political/population unit, humans are able to predict wars with a seemingly great deal of accuracy. From 12 - 18 years before a major war onwards, the balance between males and females is disturbed, and as if on some cosmic signal, more males are born in order to be at the peak of their fighting prowess for the war.
It's not really so, as my reflections led me to see. A more acid composition of human body chemistry leads to selection in the woman's vagina and uterus, disabling more female sperm and thereby allowing more male sperm to succeed, across an average population. So it's really just a simple body chemistry change. But what triggers this change?
It turns out that stress and unrest and physical stress from lower food supplies can cause a marked change in our body chemistry towards the acid end of the scale. So this "check and balance" is something that can be explained quite well.
In a region, the population of humans grows slowly until it's filled the niches and is beginning to exceed the supportable population. There is increased bickering and fighting over ever more scarce resources, and some strength is needed in order to prevail. Therefore, the genes of parents whose response to such stress is the bearing of more male children will survive more readily to the next generation. Those that don't, get killed in the time between the birth of their girls and the end of the Big Fight.
Because, of course, when you have a few hundred extra testosterone-laden young men in the area, there is going to be violence and barbarism and if you're lucky, they'll remember that they're your son and not kill you out of hand along with everyone else. The fact is that when this occurs in a larger region, then war results. War kills and clears out a lot of the excess population, so instead of the population crashing in an uncontrolled way due to natural famines or whatever, it's a more controlled cull.
And you don't even have to know about how this works - all you have to do is to be able to make more boy children than girl children in times of stress, and then be able to hang in there for about 15 years...
So now here's another application of that checks and balances system that seems obvious to me. On the one hand we have Global Warming, building up inexorably year after year, each year taking away another previously arable strip of land here, a water body there, reducing the capacity of the land to support us all. It's a situation that would stress the calmest of bodies, and in fact for a while now, male births have begun to outnumber female births all over the globe.
For a bit more proof that one of those descents has begun, look no further than your TV news - senseless violence, disregard for others' lives, a rising population of young men with no outlet for their combined testosterone storm. We're somewhat more civilised now than we were a few hundred years ago, and war has become a business proposition with risk analyses and plans that take into accoutn factors such as Mutually Assured Destruction.
So our young men, instead of dying in a melee that is designed to ensure the survival of the strongest and fastest, are still out there, only not quite so young any more. The psychological changes have already been triggered but have no outlet, and there are regions of the world under survival stress right now that would have no hesitation in unleashing their young men in order to ensure their own branch survival - if only they could get to us.
Also, please note that with the restraint we began exercising in the last millennium with regard to war, we've shifted much of the survival value away from lightning-quick, brawny, but not very intelligent humans to a human much more inclined to use brain power to solve their problem. And one of the things that this brainpower has given us is nuclear weapons. Now we sit on this cleft stick, where we have the means to end a large proportion of the world's races and populations - but at the expense of losing a great many of "our own..."
The population/resources imbalance gets worse with every year that passes, with every increase in world population, with every 0.5 degree C rise in average temperature every few years. Oh and did we mention that a use of nuclear weapons would cause a definite nuclear winter?
So let me get this straight: We're at the mercy of global warming, caused because too many people are exploiting too many of the resources of the planet, and we have a device here which could reduce large numbers of the population in a very short time - and as a "bonus," it could reduce global temperatures within a week? Only - it's indiscriminate and will kill anyone and everyone? And that's keeping our fingers off the big red button?
And now, a lot of those countries that have been itching to send their young men into our country but were unable to afford to do so, they have the same kinds of devices, which they can send into our country? But we're all holding off because of the M.A.D. scenario and the fact that we're civilised humans? We're civilised, oh yes. We'd never lob a handful of nukes out at other nations' major population centres because that way we'd be the ones with the largest population and the highest chance of our race surviving the 5 to 15 years of nuclear winter, oh no...
I need only remind you that in the last few weeks, Haiti has descended into anarchy because there was a natural disaster and now the people there are willing to do anything to get their hands on food and water and medical help. And leading statesmen have voiced the opinion that "if there's no food aside from what's in those shops, then it's not looting." In other words, a relatively minor (on the global scale) disaster is considered justification enough to do whatever it takes in order to ensure your survival.
Really - what could possibly go wrong in the scenario?