This content originally appeared on Go Make Things and was authored by Go Make Things
Today, I want to talk about squirrels, and visible natural selection in action. Let’s dig in!
How this all works
Natural selection is one of the main processes that drives evolution.
When DNA splits, replicates, and combines to make a new being, sometimes it makes a mistake and introduces a mutation. Often, those mutations do nothing at all. Sometimes, they’re actively harmful.
But every now and then, they provide a benefit.
Individuals with that mutation are more likely to thrive, and thus more likely to pass that mutation on. Over time, the mutation becomes “the norm” rather than the deviation.
This is how evolution works.
Squirrel!
When I was a kid, nearly all squirrels ran in squiggly, unpredictable patterns. This makes it much harder for birds and other predators to catch them.
It also makes them a lot more likely to get run over by cars, because they’ll often run out of the way, just to zig-zag back under a tire at the last second.
About five or six years years ago, I started noticing that some squirrels were running straight across the road rather than in a zig-zag pattern. Not all squirrels, but some.
This year, a majority of the squirrels (but again, not all) run straight.
While this makes them more vulnerable to natural predators, it provides a distinct advantage against cars.
I live in a heavily wooded area, where birds don’t necessarily have direct lines of attack, so it’s possible the zig-zag pattern provides less of an advantage where I live than it would in a more open environment.
Regardless, it’s been really cool to see natural selection play out in my own lifetime.
It’s often a slow process, so being able to observe a phenomenon I’ve read about and studied in my evolutionary anthropology classes has been rad AF!
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This content originally appeared on Go Make Things and was authored by Go Make Things
Go Make Things | Sciencx (2025-10-29T14:30:00+00:00) Natural selection in action. Retrieved from https://www.scien.cx/2025/10/29/natural-selection-in-action/
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