The Corpus Callosum

Here at ScienceBlogs, we've regularly posted about the thorny issue of antibiotic overuse, and the subsequent antibiotic resistance.  This is a good example of evolution in action; it's also a good reason why we need to study and understand evolution.  

But antibiotic resistance is not the only such example.  The same principle applies to herbicides and weeds.

Naturally, a good example comes to us courtesy of Monsanto, the company that everyone loves to hate.  (There is even a movie now, The World According to Monsanto.  It's on Google video, here.)

You see, Monsanto has made a lot of money by engineering crops that are resistant to their most popular herbicide, Roundup® (glyphosate). The idea is that you can plant these crops, then bathe the field with Roundup.  The herbicide kills the weeds, but the crops are unaffected.

Any biology sophomore could tell you, that sooner or later, you will get Roundup-resistant weeds.

Now it has been documented.  Roundup was first used in 1976.  In 1996, Monsanto introduced Roundup-ready soybeans.  No Roundup-resistant weeds were detected before the widespread use of the resistant crops.  Even then, it took a while.  But now...

Glyphosate-resistant johnsongrass in Mid-South
Mar 19, 2008 10:09 AM, By David Bennett
Farm Press Editorial Staff

Johnsongrass, the latest entry to the lengthening list of glyphosate-resistant weeds — in both Arkansas and Mississippi — was announced in mid-March. It is the first glyphosate-resistant warm-season grass found in the United States.

“We’re not trying to push resistance in these weeds,” says Bob Scott, Arkansas Extension weed specialist. “But there’s close to 5 million acres of Roundup Ready crops that get two or three applications of Roundup every season. Plus, we’re using Roundup as a burndown.

“It’s inevitable that such weeds are produced. It’s hardly a surprise.”

Johnsongrass found in a Crittenden County soybean/wheat field is the fifth glyphosate-resistant weed discovered in Arkansas. The others: horseweed (also known as marestail), common ragweed, giant ragweed and Palmer amaranth, a pigweed...

Johnsongrass (Sorghum halepense) is notable because is it an invasive species that can be toxic to livestock.  

In the long run, it may not matter, since industrial-scale agriculture may not be around much longer.  The thing is, the genetic modifications are now in the wild.  There is no way to put the genie back in the bottle.  It is not possible to fully anticipate the consequences.  

One could argue that the benefits outweigh the risks.  After all, the more food we can grow, the more people we can feed.  It would be nice to eliminate hunger.

But, what if our ability to engage in industrial farming is time-limited?  that is, what if we can only do it for a few decades, before the petroleum necessary for this kind of farming becomes too scare to be used for this purpose?  What is no alternatives are found, or if they are found but not deployed?

Then, we will have grown a population of humans that is too large for the planet to support.  Many of them will die.  Sure, some people will have made a lot of money off the scheme, but does this really make sense?