The insane biology of the dragonfly (2021) [video]
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They're as closely evolved to what is the biological equivalent to an attack helicopter as possible. Seeing them hunt will make you very happy that you're not born as a small insect. I've found more than one caught on the inside of a large barn that was open on one side, they'd keep on banging into the windows on the closed side because that was the most lit up part of the barn, for all their technical advantages and various optics they are not able to fly back out of a box that they fly themselves into even though it is perfectly open on one side. They will just keep on trying until they exhaust themselves, then you can pick them up carefully and release them again outside the enclosure, hopefully to catch a meal soon with the remaining bit of energy after a rest.
I wonder if there is any evidence for noticeable adjustments in insect navigation.
Some birds also get confused by glass, although they do seem better able to consider an alternative (e.g. an open door) when one presents itself. My dataset is the small number that sometimes get into my shed when the door is open.
Tangential glass/bird related story time. I occasionally see small birds pecking at their reflection in glass. I once saw a Long-Tailed Tit pecking at my shed window and watched it for a few seconds. And then it went one way, and the reflection went the other! That's when I realised that there was a bird on the inside as well. Cue rescue mission (opening the shed door).
Though the light I think would almost always lead the way out in these cases
My lasting impression of them is from a forest walk a decade ago, where I was surrounded by hundreds of them, and I found them super clumsy. Every step I took I spooked a couple, and they would fly as fast as possible in a fixed direction, which resulted in dozens of them slamming into trees and knocking themselves out with an audible thwack.
There must have been thousands of then flying around on the 29th January.
While bicycling through the forest in my youth, there was a small lake beneath a swampy area next to a small farm with cows and horses. Also many fawns/deer not far away.
They really thrived there, bodies large as a fat cigar. Every time I sped by that lake, they escorted me for a while. Going about 40 to 50 kph. Effortless. Like on rails, but almost instantly 'hopping' from one rail to another. Up, down, more near to my head, back away. For maybe 500 meters. Then turning back almost on the spot. Their checkerboard patterns glittering.
Very strange magic :-)
Except for dragonflies, all the other insects which are agile fliers achieve their agility by using only 2 wings, because 4 wings that are not exquisitely controlled are a hindrance, not an asset. This is done by either not using one wing pair for flying, as in flies, or by having a mechanical linkage between the 2 wing pairs, making them work like a single pair, as in wasps or hawk moths.
While most flies are no match for a dragonfly, there is a fly family, the robber flies, which look like dragonflies with 2 wings (i.e. they have big heads with big eyes and a long narrow body, though not as long and narrow as most of the less stocky dragonflies). The robber flies routinely eat dragonflies, catching them easily during the flight.
This guy in Japan posts his various experiments in ornithopteria. https://youtu.be/dHIF_2OsA_8
I don't know which type, if either, will be more practical to build as materials technology improves.
I made a video a few months ago about how to befriend dragonflies. They'll let you pet them if you have the right approach. Message if you'd like to see. Not trying to spam youtube vid/self promote.
Super not proud of the video quality/editing, btw. =D
"Good stuff" is around 8:40 if you want to skip ahead.