On The Continent, there exist many cultures, most of which can be generalized as belonging to four major races: Upperlanders, Outerlanders, Lowerlanders, and Middlelanders.
Due to tens of thousands of years of isolation, a chasm of biological differences developed between members of the Upperlander-Outerlander super-group and the Lowerlander-Middlelander super-group. This is especially apparent in Middlelanders, who have vastly different nutritional needs, mating strategies, and sexual dimorphism relative to other groups.
Though Middlelanders are able to interbreed with members of other cultures (especially when the mating occurs between a non-Middlelander man and a Middlelander woman), the differences are enough that members of this culture could be viewed as a different sub-species of human relative to the Upperlander-Outerlander sub-species.
Notable biological peculiarities that are common in full-bloodied Middlelanders include:
- A dependence on their staple food, yaw root. Middlelanders must eat the root to remain healthy. Without the phytohormones in the root, Middlelanders are also unable to go through puberty or have children as adults. (By contrast, Lowerlanders are not dependent on the plant, and Upperlanders and Outerlanders are altogether intolerant to it.)
- A tendency to have only one major meal per day (just after sundown). The rest of the time is spent snacking or “grazing” on small portions of light food. Like all humans, Middlelanders must eat fruit occasionally, but all their other nutritional needs can be met with yaw root, and some Middlelanders eat nothing except for fruit and yaw.
- An enhanced ability to carry twins and triplets to term, and a higher propensity for giving birth to both identical and fraternal twins (sometimes at the same time). This was an adaptation due to historically high infant mortality, though the survival rate for children is much higher by the era of Goda’s Slave. When Middlelanders choose to occupy an area, within a few decades, the local population explodes. The average Middlelander marriage produces six children who survive to adulthood.
- Enhanced night vision. Middlelanders cannot see in pitch darkness, but are able to see in very dim light. This is an adaptation from their close relationship with the yaw plant, which requires tending in the dark. Middlelanders have visible eyeshine at night, which may startle foreigners and is the root of quite a few local legends in the cultures they have occupied.
- For similar reasons, Middlelanders have a naturally multi-phasic sleep cycle. Most Middlelanders sleep two to three times per day, in blocks of about two hours long. Typically, this sleep manifests as two blocks at night (split by a block of wakefulness) and one block during midday. Middlelanders are therefore awake through most of the night and almost the entire day, sleeping only four to six hours in a 24-hour cycle. They do not sleep for as long as Upperlanders and Outerlanders do (who sleep in one single stretch at night), but they spend a higher proportion of their sleep time in the REM stage of sleep. As a result, dream interpretation is a major part of Middlelander culture.
- Middlelanders are tall. Middlelander men tend to be slightly taller than the average person of any of the other ethnicities, and Middlelander women tend to be much, much taller. Along with the enhanced ability to seemingly creep around in the dark (from an outsider’s perspective), this size difference earned Middlelanders a negative reputation among many Outerland tribes.
- Middlelander women tend to be territorial, more physically aggressive, and quicker to anger, especially if they perceive any danger to their children or their sisters’ children. When faced with outside threats (such as a dangerous animal or a group of hostile foreigners), Middlelander women will quickly form into spontaneously-organized mobs and brutally subdue the threat within minutes.
Although the Middlelander government has an open immigration strategy, all of these differences make for a huge learning curve for new members of the culture. In addition, Middlelanders may unknowingly impose inappropriate norms (such as the consumption of yaw) on members of cultures that they have conquered and forcefully occupied.