We think of natural selection as the kind of thing that happened long before people got involved. But one Soviet scientist believed that humans not only participated in a special kind of selection, but we ate better because of it.
When a harmless snake develops colors to look like a venomous snake, predators are wary and leave it alone. Butteflies come to resemble each other so they can all benefit from having a bitter taste. These are versions of mimicry that come to mind easily. They're also examples of a natural selection that has, for the most part, nothing to do with humans. Most examples have little to do with humans. Which is why the theories of Nikolai Vavilov were so surprising.
Vavilov was a soviet scientist who studied centers of origin - researching where geographically any given group of plants or animals evolved into what they are today. Domesticated cats have spread throughout the world, but where did they come from? Where did wild cats? Or any other wild species? Vavilov was most interested in finding out where domesticated, and other, species of plants came from. As he researched, he noted that farmers and gardeners were frustrated with the look-alike weeds that crept into their plots. It was easy to take out the plants that were utterly unlike what they intended to grow, but, not the mimics. One plant looked so much like flax that it was called "false flax," like fools gold, and was both difficult to identify and impractical to weed out of a field.
Vavilov put two and two together and came up with Vavilovian mimicry. A farmer, with a lot of work to do, can only spend so much time inspecting the fields. Any obvious weeds get pulled, but weeds that look pretty much like useful crops will be passed over and survive. Over time, the weeds that look most like the crop they're hiding next to will be selected for, and will thrive. Humans direct the evolution of plants - or plants get better and better at tricking humans. Vavilov postulated that this wasn't even a strictly one-sided relationship. It's quite possible rye and oats got their start as foodstuffs by mimicking established crops. Perhaps they were slightly modified over the years until they became as useful as the plants they grew beside, or perhaps farmers just stumbled onto the fact that these "weeds" could be edible. Either way suddenly humans aren't an observer in the process of natural selection for mimicking abilities. We're one of the reasons it continues.
Top Image: fir0002
[Via Mimicry In Plants.]