I recently saw an article about wildfires in Oregon, which are much worse than they would have been naturally because of the conscientious efforts to prevent forest fires in past decades. (Remember Smoky the Bear?) Without human interference, forests burn frequently enough to clear out underbrush and make room for new growth. Without periodic fires, the underbrush keeps accumulating to build up a copious supply of fuel, so when fire does eventually break out, it's disastrous.
That phenomenon is only one example of how human good intentions in manipulating the natural order can generate unforeseen negative consequences. Back when wolves were considered dangerous pests that ravaged livestock and attacked people, wolf packs were systematically eliminated in the U.S. More recently, they've been restored to their old habitats, thus repairing (many researchers believe) damage done by their removal. There's a theory that reintroduction of wolves to Yellowstone Park, through predatory pressure on elk, allows the growth of certain trees (whose young shoots and saplings elk graze on) that beavers need to thrive:Wolf Reintroduction
Everybody knows about the rabbit overpopulation in Australia, where introducing bunnies as a food source for colonists seemed like a good idea at the time.
Proper hygiene to eliminate disease-causing germs has saved millions of lives. Yet it's recently become known that a too-clean environment in infancy and early childhood makes children more likely to suffer allergies, asthma, etc. in later life. Apparently a little dirt is good for kids! Doctors used to recommend postponing introduction of potentially allergenic foods such as peanuts and wheat until well after the first year of life. On the contrary, new studies suggest that early exposure to such substances actually reduces the risk of becoming allergic later. The same principle seems to apply to pets; it's nice to know for sure that a lifetime surrounded by cats hasn't harmed our offspring.
Many decades ago, some doctors recommended that pregnant women take up smoking to lose weight! In the early twentieth century, feeding babies formula from bottles was the modern, "scientific" thing to do. My first obstetrician, an elderly man in the mid-1960s, must have been trained when this attitude prevailed, for he actually tried to discourage me from breastfeeding. (We moved to a different state in the middle of that pregnancy, and I'm glad I stuck to my plan even though nursing instead of bottle-feeding was still rather rare then.)
In the American Southwest, goodness knows how many millions of gallons of water are poured onto lawns to make people's yards resemble eighteenth-century English gardens, rather than cultivating plants native to the climates and ecosystems of those regions.
To paraphrase an old TV commercial, it's not nice to mess with Mother Nature—or, at least, we should investigate all possible angles before we do. Something to keep in mind when we eventually colonize other planets.
Margaret L. CarterCarter's Crypt