Yes, you need some ultraviolet to attract insects. That's why bug-zappers have near UV lamps. They're usually compact fluorescent bulbs. Some ads say 365nm is the right color.
wow this would be a neat twist if true - we all defaulted to the negative explanation of having killed them all where a much more positive explanation might be that we're no longer luring them to their deaths at the leading edge of automobiles?
I guess it is most likely some combination of the above, but if there's any evidence it would be a neat reframing
The streetlights in my neighborhood still have the round photo sensors on top, that have something like a watt of standby current for the sensor itself. I don't think they're trying hard to save powwer.
The article bluntly states: "Moonlight contains ultraviolet (UV) and infrared wavelengths because it is merely reflected sunlight. Insects cue on UV, believing it to be the moon. . . . Incandescent lights transmit UV but LEDs do not. Insects are far less attracted to LED."
However, my mind developed a similar conjecture to your's: what if the common frequencies of PWM occur within a kinetic visual blindspot of insect vision, like human saccades [0] in the novel Blindsight [1], so that insects are not aware of the LED at all?
I think it’s to do with the LED flicker. You can sometimes see it in your peripheral vision (ie your light/dark receptors) but your RGB cones aren’t as good at spotting it.
Insects eyes are biologically very different.
With LED lighting, if you have lots of spot lights in the ceiling and and open door, you’ll likely find that the light leaving the house is a bath of reflection from different sources inside the house and that likely cancels out the worst of the flicker.
I wonder how much of it is also the LED flicker. If I was a small bug and moving quickly with a high visual refresh rate, I would probably hate the experience of the LED flicker
There are odd visual illusions though, like humans perceive the Wagon-Wheel Effect even though there's no obvious reason it should happen. This is the effect where the speed of a rotating object varies depending on its sync with a discrete exposure period.
You mention it yourself, these illusions only occur with "discrete exposure periods". This is moreso related to video recordings and less about how the eye sees actual physical objects. Such illusions do NOT occur with natural light.
I highly recommend the pop science book An Immense World by Ed Yong to disabuse you of this notion. There is a sort of refresh rate (not exactly the same but good metaphor) for everything at every level of living being we study. It gives enough information for you to read the actual studied should you have more questions after reading it.
But there is a neurological component in "optical processing" that can be modeled as a discrete rate of update although the underlying physiology is still being investigated.
Yeah, i know that's how the physics works, but effectively my computer monitor doesn't flicker for me but a strobe light does. Whatever the proper term for that is what I'm talking aobut
Try walking outside in a clear night. Look up, notice some stars, or aircraft lights. Now rotate in place, and see how low your vision's FPS is in the dark: the rotation will be visibility jumpy.
An insect, with its much simpler visual processing, and facing a bright light, will likely achieve a much higher FPS, sufficient for the sub-kilohertz flicker to be very visible.
For a game i tried to model the behavior of our eyes in the dark and read up on a lot of that stuff. Not once was there a suggestion of jumpy vision. And that is also not my experience. In low light things begin to smudge, lots of ghosting the further in the periphery of your view they move in.
I wonder if it’s only the UV that makes a difference. I have some Yuji SunWave bulbs (and the NIR versions). Would be interesting to test those at night against normal LED bulbs and incandescent.
I guess it is most likely some combination of the above, but if there's any evidence it would be a neat reframing
The thing that insects can see and we don't is the rapid flashing of a PWM power controller.
I wonder if these streetlights have power saving fade-ins as the nightfall approaches instead of clicking on at sunset.
Like - https://doi.org/10.1109/CSNT51715.2021.9509652
However, my mind developed a similar conjecture to your's: what if the common frequencies of PWM occur within a kinetic visual blindspot of insect vision, like human saccades [0] in the novel Blindsight [1], so that insects are not aware of the LED at all?
0. https://www.ncbi.nlm.nih.gov/books/NBK10991/
1. https://www.rifters.com/real/Blindsight.htm#:~:text=%22There...
Insects eyes are biologically very different.
With LED lighting, if you have lots of spot lights in the ceiling and and open door, you’ll likely find that the light leaving the house is a bath of reflection from different sources inside the house and that likely cancels out the worst of the flicker.
They didn't say no bug ever goes to any led light.
https://en.wikipedia.org/wiki/Wagon-wheel_effect
https://research.tue.nl/en/publications/subjective-strobosco...
Try walking outside in a clear night. Look up, notice some stars, or aircraft lights. Now rotate in place, and see how low your vision's FPS is in the dark: the rotation will be visibility jumpy.
An insect, with its much simpler visual processing, and facing a bright light, will likely achieve a much higher FPS, sufficient for the sub-kilohertz flicker to be very visible.
We use UV/IR combo Flame detectors at work for this purpose.