"I wish we could keep him in the house...he's so cute! But Papa says that if we move them away from the lake, they'll die! And if they die, we can't eat their poison-sweat! So Prickles and I will just have to be friends from a distance, I guess." - a young Spinelander, circa 7500 AC
The Glacial Terrapin is one of the only creatures farmed in the Spinelands,
the others being Crag-Goats
and select flocks of sheep
Despite the harsh and unforgiving winter ecology and the fact that they are cold-blooded lizards, the Glacial Terrapin has not only settled on the icy shores of the mountain lakes, but it has evolved to keep its own body warm even amidst the snow and ice. The temperature near the lakes is such that the water hardly ever freezes solid. When it does the Glacial Terrapin goes hungry, since it spends much of the time chewing brittle stalks of Fimberther
that grow in the frigid shallows of the lakes.
As their body digests this it creates a chemical compound that sits in little glands near the neck, armpits, and base of the spine. This chemical compound causes the body around it to heat up. When the Terrapin gets too warm or ingests too much food it will excrete the chemical. It can also spray up to five feet away in self-defense, but if this is utilized too much it will cause their body temperature to drop, and the iguanas will slow down.
It is posited that this chemical excretion is what helps keep the water from freezing over. It also explains why the Glacial Terrapin is tethered to the low-valley lakes and is found nowhere else in the world.
The people of the Spinelands purposefully build their villages very close to lakes with Glacial Terrapins in them. Their youth have the duty of going down to the lake every morning and breaking any ice that has formed near the shoreline. They make sure the Fimberther is growing thick and strong, and that no predators are troubling the Terrapins. They will also check on the eggs, which are laid in the onset of winter and hibernate until Spring, at which time they begin to grow and hatch.
When it is time to harvest, young men and women will go down to the lake wearing heavy oil cloths. Shielding their faces they approach the terrapins, who either accept their fate calmly or, if they are young, will begin to panic and spray acid. The acid slides off the oiled cloth and does no harm. Eventually, the humans wrestle a terrapin still and begin collecting the acid by holding flasks up to the squirting glands, massaging them if necessary. It isn't particularly sightly work, but it is extremely useful.
The purpose for all this is that the chemical created by the Glacial Terrapin is not fatal to human physiology. How this was discovered is a question of constant debate. A few drops of Ice Dragon acid in liquid is a preventative against hypothermia. If someone is suffering from severe cold and is forced to drink acid-laced water or soup, they will shortly feel a pleasant tingling in their limbs and a burning on their tongues that lasts for an hour or so.
The downside to this is that an overdose of Ice Dragon acid will dissolve the stomach lining and result in paralysis and death. Outsiders may find this 'medicine' a frightening and worrying idea, but in reality it is just another dangerous but necessary custom for the Spinelanders. Their ecology is already extremely fragile. If the Glacial Terrapins fail to protect their eggs or the lakes freeze, there will be no comeback for them. In a sense, like the Spinelanders themselves, they live on borrowed time.