What gets me is that sexual selection rapidly leads to sexual dimorphism, so if it isn't going to result in significant physical differences in this setting there has to be some way for members of society to figure out who has complementary parts for making babies. Animals that lack it in the real world usually have behavior patterns that indicate their role in mating, like
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.
Here speech patterns, posture, and clothing all appear to be more or less unisex unless I'm missing something. So what's going on? Smell? Victorian style debuts where everybody learns who's ready to have a baby? Public database? Everybody just asks what's in your pants on the first date and potentially gets disappointed if they're looking for kids long term?
If whatever alien language they're actually speaking has gendered self pronouns I suppose that would probably be good enough, but I'd assume more differences would pop up quickly. Maybe monos are generally more fashion conscious and extravagant to try and impress females, like birds or 18th century gentlemen, and Fiona and Cleo are just bucking trends by dressing in more casual clothing.
I hope Episode 5 features Ashe getting baked and watching a documentary narrated by world renowned biologist and nature presenter Daveigh Attenborough to explain all this.