Many smart people we spoke with, including entomologists and wheat farmers, speculated that maybe the cars have changed, not the bugs. As vehicles become more aerodynamic, the thinking goes, their increasingly efficient airflow whisks the bugs away from the windshield instead of creating head-on splatters.

But when we called experts in the arcane art of computational fluid dynamics, they sounded skeptical. Yes, today’s sleek sedans can have half the drag of the land boats that ruled the road just a generation or two ago. But that improved airflow won’t do much for a bug.

…

So in our little thought experiment, which makes the depressingly accurate assumption that bugs are a finite resource, our bugs-per-windshield metric would have been cut by two-thirds even if the number of bugs had remained constant. And it hasn’t! It’s fallen precipitously.