Microevolution In the Backyard

MICROEVOLUTION IN THE BACKYARD
Or, Confessions of a Lazy Gardener,
a Late Lawn Mower,
and a “Creative” Dental Patient

I admit it—I’m a lazy gardener. I like to be out in the yard watching things grow, but I don’t like digging in the muck all that much. My motto is “Throw it in the ground, weed and water at least once, and pray to God for some sort of harvest.” Thankfully, God usually delivers a yield far beyond what my efforts deserve. Plus, time in the garden gives an added benefit of being able to watch God’s creation in action. In my own backyard I’ve been able to notice some small evolutionary changes over the years that illustrate one of the main issues in the creation-evolution debate.

For instance, some years ago I put a few cherry tomato plants in my backyard, and got a fair harvest. Then I left many dropped tomatoes on the ground and didn’t clean the garden bed till next spring. By that time, numerous “volunteer” tomato plants were coming up. I selected the most vigorous and early volunteers, let them grow to maturity, and weeded out the other volunteers. Then I repeated this annual cycle a number of times. In the second year I thought I was just getting free tomato plants. But in the third and fourth years I found that the tomato plants had visibly improved—they were bigger and bursting with fruit. (And, being a lazy gardener, I had not put down any fertilizer to make this happen. It was just selection of the most vigorous volunteers.) This is nothing new—farmers and agricultural scientists have been using this well-known principle of microevolution for thousands of years, through tens of thousands of plant generations. It makes better tomatoes and improved breeds of crop plants, often in a very short time (just a few years, as in my case). However, it never has turned plants into animals, or made entirely new kinds of plants.

Likewise, I once planted some Jerusalem artichoke bulbs from a friend’s leftovers. I was warned to hedge them in with a barrier to keep them from aggressively spreading, and to treat them for grubs that would bore into their edible roots. Being a lazy gardener, I did neither. The artichokes grew luxuriantly and spread. The first year I enjoyed both their flowers and their edible roots (rather like water chestnuts). Then in the second year the grubs moved in and bored ugly dirty holes into the root tubers, making them unfit to eat. The plants still multiplied every year, though. For the next decade I just enjoyed their bright yellow flowers. However, as each year I weeded the outliers, I found that natural selection was quietly working for me. Every year as the plants reproduced the grubs lost ground (literally). My artichokes are now almost completely grub-resistant, just as bacteria can quickly get resistant to antibiotics.

Speaking of antibiotic resistance in bacteria (often cited as firm proof that we all came from pond scum), I developed some resistant bacteria in my own mouth in just a few years time. I had a root canal that went bad, allowing bacteria to grow into a crack below the gumline. It didn’t get overtly infected, just created a bad taste that was a considerable nuisance. The tooth was doomed sooner or later, but I kept it for a few more years by swabbing the cracked side with a pinch of antibiotic powder. At first just one antibiotic worked well, but then two were needed. After 4 years three antibiotics were needed, and a bacterial culture showed several resistant microorganisms. (Yes, I finally had the tooth out, rather than have my head eaten off by antibiotic-resistant bugs.) A dentist friend of mine confirmed that it’s quite easy to develop antibiotic resistant strains of bacteria in a single patient’s mouth by treating a chronic deep dental infection with antibiotics. It happens quite frequently and in a very short time. However, such resistance has never helped a bacterium to become a yeast, algae, or protozoan. Even such a small step of macroevolution remains elusive.

My daughter is very fond of spring violets, and likes to make bouquets of them. I like to help her gather the violets. However, we’ve noticed that the best violets for bouquets don’t come from the many violets in our own yard, but from those in the vacant lot across the back alley. The reason is that the vacant lot violets sit in vases better, having much longer stems—usually two to three times as long as the short-stemmed ones in our back yard. I know some critic will say that this is only because the violets in our yard bloomed quickly on a shorter stem after they were cut. However, this effect was very noticeable even when I was a tardy mower, and didn’t mow our lawn at all until late spring after the violets had already fully bloomed and faded (much to the neighbors’ chagrin). When we discussed why this was, we realized that once again natural selection was in action before our very eyes. In our occasionally-mowed back yard, the short-stemmed variety had a survival/reproductive advantage, while in the rarely mowed vacant lot (with competing long grasses) the long-stemmed violet variety had the advantage. Once again, we had microevolution right in our own backyard. Like the Grand Canyon squirrels that developed different colors on either side of the Colorado River, the violets developed different stem-length varieties on either side of our back alley.
Darwinians often try to prove their point by giving examples of very small biological changes, or microevolution, and saying that these will add up to very big changes (macroevolution) through eons of time. They say that Darwinism is a “fact” or “law” because small inherited changes can be seen so easily. They are right that microevolution is everywhere—one need look no further than the backyard, or even one’s own body. On the other hand, we can go to the ends of the earth, track living things through thousands of generations, and find no trace of macroevolution. The extreme commonness of microevolution contrasts sharply with the extreme rarity of macroevolution. We see the first very frequently, the second never.

This tells us something profound about the living world. God obviously loves variety, and has built enough genetic plasticity into living things to give potential for incredible variety. Thus, we can have scores of dog breeds develop in just a few hundred years. Or, we can have millions of people of all shapes and sizes, with no two being exactly alike. This genetic plasticity also implies loving providence from God, for it allows creatures to survive changing and hostile environments in a cursed and fallen world. However, despite all this micro-variation, the basic kinds of creatures remain remarkably stable, reminding us of the need for a Creator to explain it all.

Romans 1:21 tells us that the amazing genius of the Creator God should be obvious to everyone. We don’t need to travel around the world to find this out. Just a little thoughtful time in the backyard can help us toward this needful conclusion.