Photo by jster91 | flickr.com

Ever since humans first took tools to the land to grow crops and construct permanent settlements, we as a species have understood that our actions have a lasting impact on the natural world. Whether it was the deforestation of areas for the purposes of expanding arable land or the silting of river systems because of extensive irrigation, the progress and upword mobility of humanity has only been possible through the modification, for good or for ill, of our physical environment. Obviously it would be impossible to live without making some sort of impact on the land, but given the technology at our disposal and the size of the human population, the ways in which we are disrupting nature are both more subtle and more dangerous than at any other point in our history.

The threats posed by human-driven climate change are often described in almost apocalyptic luridness; hurricanes, droughts, lightning storms and tornadoes are just a handful of some of the disaster scenarios conjured up in association with our continued unchecked use of fossil fuels. But there are other, less obvious, consequences of a rapidly shifting world.

Scientists in Canada studying the mating habits of wild salmon have come to the conclusion that because of higher summer temperatures arriving earlier in the year, the previously clock-work schedule of the salmon run has become disrupted. More and more salmon are making the run upstream to their spawning grounds both earlier in the year and later to avoid the searing temperatures of modern summers.

“So what?” you might ask, “It’s not like the salmon are dying.” They might not be dying, true, but they are evolving in a manner unconnected from natural, gradual processes. Human actions on a grand scale are slowly but surely forcing the salmon to adapt to a highly unstable climate and evolve in ways that we cannot predict. This forced evolution could possibly have ramifications up and down the food chain. After all, we consume salmon and thus in turn everything else the salmon has consumed during its lifetime. In the salmons’ case, the consequences are simply unknown.

However, there is a similar example of human-driven-evolution of a species where the potential for disaster is known, quantifiable, and potentially deadly. Is it some mutant freak of nature like a piranha-wasp? No, dear reader, it is much more chilling: corn. The same corn that makes up 69% of the average North American diet in the form of high-fructose corn syrup, cereal, bread and other processed food. And the same corn that, in some cases, makes up for 93 percent of the hamburger or hot dog on which you are chowing down. And given that the majority of the corn produced in the Western world is so-called Bt corn (genetically modified to include a pesticidal bacterium gene), we are indeed in a bit of a pickle (excuse the mixed vegetable metaphors) when the pests that Bt corn supposedly ward off begin evolving natural resistances to the strain. Mix an agriculture industry almost pathologically obsessed with growing corn with a rapidly reproducing – and thus evolving, if we recall our lessons in natural selection – species such as the corn borer or the corn rootworm and what we have is a recipe for highly unstable food prices in the most optimistic scenario, and widespread starvation in the most alarmist scenario.

Regardless of where you stand on the fullness of the glass debate in this situation, one thing is clear: There are long-term consequences to playing with our food. 10,000 BC this ain’t. We need to start having conversations about our stewardship of the world before it’s too late to afford a Big Mac at the nearest McDonald’s.