The easiest path it takes, the easiest path it makes

In the stream down on the golf course, there is a rock that splits the flow of the water in half. This rock is a new element of the stream - I’ve been mucking about in the mud down there for years, and have surprisingly many memories about what it all looks like.

I’m no streamologist, but my theory: this split in the stream around this rock only exists in late fall and winter. Q: why?

Answer: water flows down the path of least resistance. And with its flow, water carves a path for itself that has even less resistance.

So we would should never expect a split in a stream to form and persist, especially when the surrounding banks are soft enough that carving a deeper, easier path happens quickly.

But in the late-fall and winter, leaves clog the stream. The path of easiest flow, where most of the water goes, is also where most of the leaves go, and thus clogs occur. So the easiest path is now the other side of the split. And so on.

This analysis raises two points:

1. Living things aren’t the only systems that are understandable through evolutionary-looking lenses; indeed, approaching every system as potentially evolutionary is very informative.
2. The seasons really matter to systems in ways you don’t expect. I shouldn’t try and live the same lifecycle in the summer and winter, and should try to understand how humans have done this historically.