Population Cycles

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licking-his-chopsI recently saw a show about cats — a National Geographic program — which talked about their special adaptations for hunting and how they became domesticated. They actually chose to be domesticated by humans. They were attracted to where people live, catching mice in our barns and houses, eating dropped food (or getting handouts!), using our shelter, and overall, they realized that living with people is advantageous to them. The other cool thing is that they can also quickly go feral and live totally on their own again in the wild. So although they are domesticated, they can reverse the process at any time! This explains my usually mild-mannered kitty suddenly going berserk when he gets overstimulated, for example. But he’s nothing like the cat I had that went feral.

His name was Arnie, named after Arnold Schwarzenegger, and we used to let him go outside, and then had to track him down at night to get him back in. One night, he wouldn’t come back in and was nowhere to be found. For several days we looked all around the neighbourhood, but no sign of Arnie. Eventually, we stopped looking, but an ad in the paper about a month later described our cat found about 20 blocks away — sure enough, it was Arnie. But he wasn’t the same. He was totally wild, quite scruffy looking, had signs that he’d been in some fights, and really did not want to be indoors. He spoke through his body language, as cats always do, and scratched my husband on the eyelid. After that, we let him out and sort of stopped looking for him to come in at night, and he was gone for good.

But coming back to the idea of cats eating mice and other vermin… In the middle ages, vermin (love that word!), and therefore cats, thrived in cities, but also around that time, people started getting really superstitious. They started accusing each other of being witches, and many cats were killed too, believed to be the minions of darkness. You have to admit, they can be kind of spooky — silently appearing out of nowhere, slinking around, eyes glowing in the dark… In any case, superstitions got the best of them, and they killed off almost all the cats who would have killed the rats who carried the fleas who carried the Bubonic Plague. An estimated 75 million people died in that plague — 30-60% of the population of Europe at the time, and the plague spanned from China to Northern Africa and throughout Europe. It turns out cats are partially immune to the Bubonic Plague! Isn’t it ironic that cats could have saved humans if we hadn’t been so irrational and superstitious. (Hmm… I wonder if we have any superstitions or false beliefs now that are affecting our future…)

I’m currently reading a great used bookstore find, Nahanni, by Dick Turner. It’s about his adventures in the Northwest Territories and Yukon in the 30’s – 50’s. The explorers of the time truly lived off the land; they literally walked a hundred miles a year in the wilderness maintaining trap lines, hunting, and doing whatever they had to do to survive. Turner observed the land and the animals, and he noticed certain cycles — the typical predator-prey cycle where, as the moose population grew, so did the number of wolves. Then, as the wolves decimated the moose population, they starve or have to move to other areas. Predator and prey… it’s a natural cycle, and although we don’t seem to like it, that’s the way the natural world is. We especially don’t like being prey! Come to think of it, we aren’t fond of starving either! We want to be the top predator, but never starve. Anyways, Dick Turner noticed another cycle: periodically, the rabbit population would climb, until 3-4 years after peaking, a disease would come and rapidly wipe almost all of them out. Then, they would gradually start reproducing again, and even though they had many predators, they reproduced so fast, they would eventually reach that peak-disease-decline part of their cycle again. The cycle repeats about every 7-11 years.

So… could this ever happen to us? We aren’t exactly rabbits, but really, man has no major natural predators. Sure, grizzlies and wolves killed and ate some of the pioneers, and still get a few people a year, but it would seem that man’s main population control is in diseases. Unless you consider self-predation — war still kills far too many of us with far too few working on preventing it… in this way, we are our own predators. But it seems possible that diseases might be our population-control cycle, if we get too crowded. We are getting better and better at curing and preventing some of them, yet we still die of cancer, heart disease, diabetes, and more self-inflicted diseases. And we’re working on eliminating other things that kill us — accidental deaths and crime in the developed world, and hunger and various diseases in the developing world (malaria and AIDS come to mind). We are working so hard to maintain and extend our lives, and reproduce, on a planet that must eventually have a limit to the amount of life it can support. Unless we get a lot smarter about how we grow food, purify water, and consume natural resources, it’s possible that another Black Plague might come to reduce our population.

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A few minutes ago, as I was writing about death, my heart started pounding a little. It’s uncomfortable, yet it shouldn’t be. Death is a part of life. A flower, so beautiful and fragile, must die to produce the fruit it is meant to produce. Perhaps we are the same, but we are so attached to this life, and the superficial things in it, that we can’t see any good in death. And we get sidetracked, when we could be living fully in the moment… and so we miss the most beautiful parts of life and death. Perhaps we would do well to be like a flower, happily enduring the heat, the cold, the rain, the wind, and always turning to face the light. To just be. To stop stressing about the future, including diseases, and just be.