Merfolk

Overview

Most merfolk live in close conjunction with shores, in shallow waters near the mainland, with some communities habitating island waters. These merfolk occupy one of two subspecies¹: iarans or nix. The third species, unknown to the vast majority of other merfolk and tellurans alike, is the chimerae. Chimeraes live in much deeper waters than iarans and nix, and as such rarely, if ever, interact with other species.

Merfolk evolved as predators, using their looks and song to lure tellurans to the water to consume. Their humanoid forms are a result of this predation of mimicry, as is the vocal ability of iarans. Within memorable history, though, extant merfolk have not preyed upon other humanoids, but rather coexist with them.

Post-cataclysm, merfolk retained much of their sciences, infrastructure, and history, unlike many telluran societies. Especially in southern waters, merfolk were protected from the full fallout of the eruption, and such didn't suffer as complete a start-over as others did. As a result, post-cataclysm merfolk are known for their advancements in science and technology, especially in the world of medicine.

A male mer is a merrow, a female mer is a lamia.

Language

Merfolk share a signed native language, Optimana, the linguistic precursor to telluran Sign.

In contrast to Sign, Optimana lends more focus to handshape than movement, as the density of the water they must sign in makes fast, efficient sign language more difficult if motion is the focus. The motion in Optimana is larger, slower, and less emphasized. Instead, the shape of both hands, their position relative to the body, and the placement of the caudal fin are used to distinguish words, phrases, and grammar.

In contrast, Sign lends more emphasis on quick, short motion, a single hand's shape, and movement of a single hand relative to the non-dominant hand's position.

Merfolk do usually know Sign, and often know Solan as well, but Nix, being mute, cannot speak it. Most telluran settlements in coastal areas have large populations of people who know Sign.

Physiology

Merfolk have two distinct sets of gill slits: a cervical set and a thoracic set.

The cervical set is uncovered in all subspecies and allows water into the gill cavity. There are three slits on both sides of the neck, six in total.

The thoracic set is covered by operculum in nix, but uncovered in iarans and chimereas. Both have ten total gill slits, five on each side along the ribcage.

A nixie's² gill slits are covered by two sets of operculum per side (four total), and can move independently of each other to draw water through the gills. The top two operculum cover two slits per side, while the bottom two cover three each.

Because iarans lack operculum, they can suffer from breathing problems in the case they are stationary in still water. Either they need to be in a place with some semblance of current, or they need to move to move water over their gills.

The actual gills are present in rows inside a small, narrow cavity that spans the space from the neck to the bottom of the ribcage, drawing oxygen from the water as it passes over them, entering through the cervical slits and exiting via the thoracic.