Adult weight: 100-300 kg
Adult length: 2 meters
Visual range: infrared through cyan
Diet: Omnivorous, focus on fruit and nectar
Bug ferrets (or just ferrets) are from an iceball planet where most organisms live underground in the tropical band of the otherwise glacial planet. After millions of years of subterranean life, the tropics are now riddled with vast networks of biologically formed tunnels, caves, and seas. Ferrets rose from a strain of endothermic and highly social omnivores. They have both an endoskeleton (mostly for muscle support) and an exoskeleton covered by a thick layer of subcutaneous fat, skin, and dense, highly sensitive hairs and whiskers. Ferrets wear minimal clothing, if any, because it irritates their delicate hairs. Their central nervous system goes down the length of their body, and they are very fast at picking up sensory signals and reacting to them.
When it comes to bones, bug ferrets are a weird case. Their distant ancestors were exoskeletal and molted to grow in size. A clade split off from this group that had less molting events during life, instead molting from an exoskeletal larvae into an adult form that had a layer of fat and skin over the skeleton, allowing for continuous growth and reshaping of the bones on all sides by living cells. Bug ferrets are descendants of that clade, but now their only true exoskeletal stage is embryonic. The bug ferret exoskeleton is now tough but springy plates that run the length of their body like a living armor– very useful for shoving your body through dirt and surviving tunnel cave-ins.
Some bones on the face, like the mouth parts and eye caps, are still technically exoskeletal and get shed annually. The tradeoff for this body plan is some loss of flexibility and very few nerve foramena linking the brain to the skin. If one of the foramena is damaged, then a large area of the skin can lose sensation. Their whiskers help make up for this wiring problem, as they attach to roots beneath the bone plates.
Ferrets also cannot see blue through violet, it appears as greenish grey or black to them. They color their things red through green, though they can unintentionally make things blue or violet and have no idea. They can also sense infrared, and as an extension of that, heat is sort of a color to them.
Ferrets have highly variable sleep patterns, since there is no real day cycle underground. They will frequently take short 1-4 hour naps, and every 30 hours or so a household will usually all pile into one room and snooze together. Compared to everyone else they are very light sleepers, but are also quick to fall back asleep again.
Bug ferrets are used to much lower oxygen environments than everyone else, but higher O2 concentrations don’t harm them. Ferret gas mixes feel kinda stuffy to everyone else though. They have a specific organ in their body to help cope with excess CO2 buildup in their blood called a calciferous gland, which converts the gas into calcium carbonate.
Ferrets are very tolerant of low oxygen and cold (their unique mix of hemocyanin and chlorocruorin is great for carrying oxygen in these conditions) but not great with heat… they’re known to pass out at 90 degrees Fahrenheit or less, which other species consider merely annoying. They can also start to get light-headed if oxygen levels are too high. Their ships and terraformed bubbles are perpetually stuffy and chilly.
The chemosynthetic plants ferrets have do metabolize CO2 into O2 when building sugars, but they release a lot of it in the soil and it tends to leak out into the tunnels fairly slowly. You can hit big oxygen pockets while digging on their planet.
Ferrets are hermaphroditic, and generally speaking every ferret has a sire parent, layer parent, and an egg sibling. Ferrets usually don’t know their sire parent, since families can have like a dozen adults who all mate with each other, but the layer parent is usually known (at the very least for medical record purposes). Ferrets lay egg cases with two embryos each, and egg siblings are referred to as twins. Typically the ‘twin’ a ferret is born with has higher social significance than their sire parent, so they’re more likely to know their layer’s twin and grand-layer’s twin, and etc. In place of human concepts of father/grandfather etc you typically would refer to your non-parent family and grand non-parent family (or just family and grandfamily, to make things more confusing). It gets even worse when you start considering the layer families and grand-layer families of every other adult in the household.
REPRODUCTIONContent warning: genitals, sexual intercourse