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Comment by dvh | Hacker News Reader

'80s cars are not exactly known for their aerodynamics...

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This is the classic "this is fine" response whenever someone posts this observation about declining insect populations and cleaning dead bugs off of cars.

However a tiny bit of investigation into this will lead you to realize that this hypothesis is false.

More than just being false, research has discovered that modern cars hit more insects than less aerodynamic cars [0]:

> The research included vintage cars up to 70 years old to see if their less aerodynamic shape meant they killed more bugs, but it found that modern cars actually hit slightly more insects.

So, given what research has shown us, we should expect there to be more insects observed if it were the case that insect populations remained stable while cars became more aerodynamic.

0. https://www.theguardian.com/environment/2020/feb/12/car-spla...

Not if the aerodynamic cars from a decade ago significantly impacted insect populations.

Less than half of 1% of the land area in the United States is covered by roads of all kinds, not including rights-of-way, parking lots, and driveways.

National Academies of Sciences, Engineering, and Medicine. 2005. Assessing and Managing the Ecological Impacts of Paved Roads. Washington, DC: The National Academies Press. https://doi.org/10.17226/11535.

There is every reason to expect that the flying insects near paved roads today are less likely to die in encounters with cars than the flying insects near roads of 40 years ago.

But it would be very difficult to measure that effect.

Right, the quote from the linked paper is:

> This is contrary to a suggestion that finding fewer insects on number plates in recent years might be attributed to increasing streamlining of vehicle aerodynamics over time. Our data show that newer vehicles sample more insects than older vehicles, and we have observed pattern of fewer insects on number plates more recently than in the past in spite of this effect of vehicle age, which is assumed to be correlated with aerodynamics.

In fact the researchers posit a few more possiblities other than collapse of insect populations that could explain their data. For example they can't eliminate the possibility that there's some change in the management of roadside verges that specifically decreases the insect population in those environments, without reducing the population in other environments.

The challenge for all the explainations which involve something other than population change is that there's now an increasing nubmer of studies using different techniques which consistently show declining populations. For example [1] uses Malaise traps in nature reserves, which presumably wouldn't be affected by roadside management practices, and finds a ~75% decrese in flying insect biomass over 27 years, whereas [2] uses light trap data to look at moths specifically and finds a ~40% decline in biomass over 50 years (and ~50% in woodlands).

Whilst it's possible to find studies that show increases in insect numbers e.g. as a result of site-specific conservation work, there's a lot of data suggesting that in Europe at least numbers are in significant decline. As far as I can tell (and I'm really not an expert) we don't understand the reasons all that well, but habitat fragmentation and pesticide use are leading theories. We at least know that common pesticides (notably, but not exclusively, neonicotinoids) are toxic to bees, and will reduce populations even at sub-lethal doses (e.g. [3]). So changing our agricultral practices to eliminate these chemicals looks like a necessary, but perhaps not sufficient, part of the solution.

[1] https://journals.plos.org/plosone/article?id=10.1371/journal... [2] https://resjournals.onlinelibrary.wiley.com/doi/10.1111/icad... [3] https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.66...

I drive over 100 Km daily. My '15 Impreza would get bugs on the windshield, but my '22 Model 3 is covered with them every evening. The first thing that I do after plugging it in is to clean the windshield, headlights, and other front-facing parts every evening. I'd do that maybe once every week or two in the Impreza.

I have been driving the exact car from this drawing for the last 25 years: Volvo 940, square as a brick.

In the 90s, it needed a weekly scrub to keep the headlights and plate visible.

I have literally not washed my car a single time over the last year. It has moss and pollen all over, but there are hardly any bug splats.

This frightens me _so_ very much.

The majority of US cars are huge SUVs and pickup trucks. I would dare say 80's cars are more aerodynamic simply by having a smaller cross section.

Not necessarily. Windshields were less curved and more vertical, body panels were much less contoured, and features like sealed-beam headlights, mirrors (if equipped), and windshield wipers were more protuberant. A 1980s Mercury Grand Marquis had a drag coefficient of 0.46, while a 2018 Ram 1500 is listed at 0.357 (less is better). Obviously some 80s cars fared better, mostly compacts like my '83 SAAB 900 (3.7, not on the list below) or sports cars. I just picked the Mercury as a typical full-sized family sedan.

Here's a big list, for anyone interested in some numbers: https://en.wikipedia.org/wiki/Automobile_drag_coefficient

Coefficient of drag normalizes relative to cross sectional area. Pointing out that a modern Ram 1500 has a lower Cd than an old Mercury doesn't mean the Ram has less drag. If the Ram's cross sectional area is 30% larger, it will have more drag than the Mercury despite having a more aerodynamic shape.

Thanks for pointing this out; I was unaware. There's also a table of cross-sections later in the linked Wikipedia page, but I hadn't paid much attention to it because of not knowing how to perform a meaningful comparison.

I have heard that a Spoon Sports modified F20c can do 11k reliably. The engine has a very long stroke for its size, and stock, the piston speeds are already higher than almost any other car engine, so that it can spin as fast as it does is pretty amazing.

Motorcycle engines, however… Some of those are 14-16K stock.

The article's title specifically mentions "number plates". All cars in the UK are required to display number plates (license plates) at the front and back. They have a standard size. They are nearly all (99% or more) in the centre and are roughly the same height off the ground, depending on model.

My first Mark 1 Ford Fiesta from 198something had its plate at about the same place as the Honda S2000 I had in 200something and the Renault CLio I have now and the Ford Transit van I also drive.

The S2000 did the best doughnuts though. Rear wheel drive, variable valves, 13,500 RPM red line and quite a lot of welly.

What kind of mods did you put on your S2000 for it to do 13500 RPM and not blow up immediately? That redline would be 3000 above any other production car sold, with the 2nd place being a motorcycle engine in an Ariel Atom 500 redlining at 10'500 RPM.

My eyes are dim, my memory is ... Whoops. Perhaps 9000 RPM is a bit closer to when the bloody thing stuttered when I overdid it a bit. It got there rather rapidly in 1st and getting into 2nd and 3rd on time took a bit of fast twiddling. No paddle flapping nonsense, just a stick that has to be moved rather fast in conjunction with the clutch.

I live in Yeovil, Somerset - the Ariel mob are from down the road - Crewkerne (pronounced something like Kruken!)

Motorcycle engines, however… Some of those are 14-16K stock.

Your s2000 had a 13.5k redline? Did you happen to have one with a Spoon engine that went 2k beyond any other Spoon engine?

Not doubting you just genuinely interested as an enthusiast. edit: saw your other reply

Somewhat off topic - Did you draw that car yourself, or did you copy it from somewhere? It's great!

This happens on my home Debian box when I mistype `git`:

    $ gti
          ,---------------.
         /  /``````|``````\\
        /  /_______|_______\\________
       |]      GTI |'       |        |]
       =  .-:-.    |________|  .-:-.  =
        `  -+-  --------------  -+-  '
          '-:-'                '-:-'

There's this assumption, not explicit, but floating around this thread, that aerodynamics somehow makes splats more difficult.

I can't really refute it, but it doesn't ring true to me either.

Insects don't even touch the car before exploding, mind you.

Last summer's trip was in a Mercedes GLK, not exactly the paragon of slipperiness.

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