hello, thank you for asking, I was basically sitting over here vibrating hoping for the opportunity to infodump more
so the things about making decisions is that it takes a bunch of time and energy and brain power to gather and assess information, and it is evolutionarily advantageous to cheat and offload as much of the work as possible onto other people. thus, there is natural selection for observing other people's decisions and mimicking them.
in a lot of critters, this means it is advantageous to watch who someone else picks for sex so you can copy what they decided was sexy when you select your own partner
the simplest version of the fly sex panopticon is basically just a 2-chamber tube where scientists can orchestrate sex shows for fruit flies.
("watch a demonstration" is scientist code for watch anorthern pair of fruit flies have sex)
you can very quickly instill a preference: cover male fruit flies with pink or green fluorescent powder, and then let a female fly observe another female fly having sex with a pink male. the observer will conclude that pink is extremely sexy and be much more likely to select a hot pink male herself. by switching the colors and the learned preference to green, you can demonstrate that this is indeed learned behavior, and not some kind of pre-existing genetic preference.
the 6-way "sexagon" was invented for this paper to test how seeing different ratios of pink vs. green males being chosen would affect the development of preference.
the cool thing about this graph is it shows it didn't matter if there were only slightly more of the the females picking pink or green males, the observer would still develop a preference for whatever the majority were choosing.
the whole paper is very cool, and absolutely worth a read:
it argues (and supports experimentally) that since preferences can be learned and passed on, fruit flies have an actual culture that can vary among populations and be transmitted to youngsters across generations.
this is super cool, because most studies proposing or examining the existence of culture in animals have been focused on higher level stuff like monkeys. if something as simple as a fruit fly can have a culture, this suggests that animal culture could have had huge effects on evolution from the ground up.
so yes, animal culture! fruit fly culture! very cool
but also an excellent evolutionary argument for voyeurism