Kuoriutuu

Kuoriutuu is a Finnish verb form meaning to emerge from a protective covering, such as an eggshell, a chrysalis, or an exoskeleton. The form is the third-person singular present indicative of kuoriutua, and it is used to describe an organism becoming free from a shell or shell-like covering in the current moment.

In biology the term covers two related processes. First, hatching from an egg, where the embryo breaks or penetrates the eggshell to become an independent larva or juvenile. Second, molting or ecdysis, common in arthropods, in which an animal sheds its old exoskeleton to allow growth or metamorphosis; a new cuticle forms beneath the old one and often the animal appears to “grow into” a new shell. Because kuoriutuminen can refer to both events, the precise meaning is usually inferred from context, and more specific terms such as hatching or molt may be used in scientific writing.

Usage examples in Finnish describe animals at key developmental moments, for instance a butterfly emerging from its chrysalis or a crustacean shedding its old exoskeleton. Environmental conditions such as temperature and humidity strongly influence successful kuoriutuminen, and disruptions can lead to failed hatching or molting. The term appears in everyday biological discussion as well as in aquaculture, entomology, and ecology to denote these critical life-stage transitions.