Another part of this could be improved aerodynamics of cars. Maybe a larger part of the insects gets routed around the cars in a laminar flow.

Could be, but bikes on the roof of the car see a lot less carnage as well. It used to be gross, and you’d need to wash your bike after an hour on the roof, but now, not so.

There even used to be spandex covers you could out over the front of your bike on the roof rack, but I haven’t seen one in years.

Nope. Still driving the same car.

These are anecdotal, but I have the same experiences in North America of inspect splatter when I was younger versus the last decade, of which there is very little.

Different vehicles maybe? A day-long summer ride through the countryside on my motorcycle and my helmet, jacket and windscreen will be completely covered with bugs.

Has anyone considered this idea? That modern computer-modeled and wind tunnel tested cars are just dramatically more aerodynamic than the insect-killing cars of our youth?

It's very pleasant to be able to go for a whole-day bicycle trip and not get any insects in my mouth. But even if cars have grown more aerodynamic, I don't think I can thank the car manufacturers for this pleasant development.

In the 1980/90s I used to cycle everywhere as a kid. I must have done at least 10 miles a week as I lived 3 miles from my best friends. And I lived in the country.

I only ever remember swallowing an insect twice. It probably happened more, but it definitely wasn't a regular occurrence and tended to only happen on hills when you were going really fast.

Also the having to clean screen thing was a thing that happened certain years, not every single year. We used to go on trips to France that we drove to, from East England to France, 10 hours of driving, and some years it needed cleaning a lot, some it didn't.

Again, I totally realise that there definitely is something happening, but the way people are talking is that there used to be a swarm of insects every year, when that wasn't the case. It was different year to year, and it looks like 1989 in Germany was definitely a 'heavy' year and not a great baseline.

I think the reduction in aerodynamic drag mostly relates to the flow of air at the back of the car, to reduce the low pressure area.. so wouldn't change what's happening at the front too much. Also, since the 80s, improvements have been minor(?), and besides, road speeds have possibly increased, which you would expect to increase the incidence of squashed bugs.

I own an old utility car (1981) not so aerodynamic and i confirm the drop of insects on the glass in the last 20 years

My first car was a 1986 Honda CRX Si, which IIRC had a pretty low Cd of 0.31. I picked up plenty of bugs with it back then.

When I was a kid, lightning bugs filled the front yard. Now, I might see one of them if I'm lucky.

How much farmland did you drive thru as a kid vs now? I live in a small city and never get bugs on the windshield or grill. When I drive out of town and thru the surrounding farmland there are tons of them. To be fair, though, I grew up in farming country and it there used to be way more than there are now if my memory serves me. It does appear that there are fewer total insects in those areas. The farmers are getting better at controlling them, I think.

On the east coast it's the same! I don't like walking outside at my parent's house because of the crazy number of bugs but anywhere reasonably developed (like the small college town I live in) doesn't have this problem.