A tortle hatches from a thick-shelled egg and spends the first few weeks of its life crawling on all fours. Its parents, old and near death, spend what little time they have left telling stories to their offspring. Within a year, the young tortle becomes an orphan, though not before it learns to speak and to survive on its own.
A young tortle and its siblings inherit whatever tools, weapons, and gifts their parents left behind. Each young tortle is expected to fend for itself. It leaves the place of its birth and finds its own corner of the wilderness in which to hunt, catch fish, and get by. With each passing year, a tortle hones its survival skills. It forms friendships with its neighbors while also respecting their privacy. At some point, a tortle feels an almost overwhelming urge to venture far away from home and see the world. It gathers up its possessions and heads into the wilderness, returning years or decades later with stories of its exploits and new skills
When a tortle nears the end of its natural lifespan, it seeks out a mate and procreates. Tortles lay their eggs (numbering in the dozens to hundreds) in a fortified compound enclosed by stone walls that are easily defensible. If no such compound exists, they build one. The parents spend the remainder of their lives guarding the compound, defending their offspring, and sharing lifetimes of knowledge before they die. When the children are old enough to leave the compound, they pick up whatever weapons and tools their parents left behind and set out on their own.