A goliath grouper gives a lecture on the intersection of mermaid and human culture.
Mermaids are not a monolith. Their populations are as diverse and distinct as our own, if not moreso. We are only one species, we bleed the same blood, we burn in the same sun (selkies are regarded as an ethnicity for most purposes as they intersect often with humans)
Most pelagic mermaids have at least some capacity to mimic the secondary sex characteristics of human females; left over from the days when they preyed on sailors by luring them in with appearance and song. This is why they are referred to as mer “maids” despite equal numbers of each sex joining the frenzy.
One cannot summarize “mermaid gender” as there is far too much variation between and within species.
Such could be the subject of an entire course, perhaps multiple courses, on that topic alone. As a human scholar and a generalist, it’s not my place to lead such a course when mermaids have been teaching and living among us for centuries now.
For short notes, however, an exploration of coastal mermaid culture will suffice. Most of the coastal populations with intersecting species grow up learning both land and sea common, or their own plus their neighbor’s native language.
In sea common, personal pronouns are not gendered as reproductive sex only matters to species with extreme sexual dimorphism. Sailors have referred to them with feminine pronouns since the first sighting, so those translating their sea common pronoun into land common will often stick with feminine pronouns as the default. This choice has no bearing whatsoever on mermaid’s reproductive sex, nor their preferred roles in society.
Those who immerse themselves in human culture beyond trade will more often than not change their human form to pick up traits that they like, completely disregarding where those traits are “supposed” to be. Their pronoun choices are just as varied and many choose to be referred to in land common’s neutral pronoun, which is often easy for human’s to grasp as a mermaid who is not displaying their faux “breast” pouches is rather androgynous.
In blended cultures, mermaids will sometimes bring “gendered” pronouns into their societies, but it is very rare that these pronouns have anything to do with reproductive sex, or even what a human would call “presentation.”
In return, mermaid culture influences nearby humans to be less restrictive with assigning pronouns and gender roles. Inland visitors are often greeted with a pronoun inquiry by human and mermaids alike. This is extremely common in blended cities.
This is, of course, only the most frequent effect the common languages have on each other. Along the more southern coasts, humans end up removing gender from their language entirely. It’s a very welcoming system.
Inland countries would do well to learn a thing or two from mermaids. Perhaps the advent of magic assisted transportation will help connect us.
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In summary, all mermaids used to consistently imitate feminine human traits, but these days adopt whatever each individual wants. A mermaid’s reproductive sex has no bearing on their humanoid presentation or pronoun choices.