Before the rainy weather came, I was able to take my new trike to the C&O Canal one day over the weekend. At one point, I passed by this bright green "field" alonside the towpath; it was, of course, the canal itself. I stopped to investigate. It turned out that the water was densely covered with duckweed (Lemna sp.).
While taking close-up shots of the duckweed, I noticed that there were numerous tiny things scampering across the surface. I had no idea what they were and so got even closer with the camera and took a few shots of them too.
They turned out to be some sort of real tiny insects minding their own business in their 2 dimensional world of floating duckweed thalli and surface tension. I estimated that they were about 1 mm long. Soon after I posted their pictures on BugGuide.Net, the knowledgeable folks there identified them as Tanysphyrus lemnae, the duckweed weevil. And yes, they are the ones who were responsible for those holes in the duckweed.
Unless we stop once in a while and pay close attention to the world around us, we are bound to miss the microcosms of evolution that are there in the details. It's too unfortunate for us that we don't have enough hours in our days to spend more time to get closer to nature.