livsfaser

Livsfaser is a Swedish term that describes distinct periods in the life of an individual or an organism, characterized by qualitative changes in biology, development, or social roles. The concept is used across disciplines such as biology, psychology, sociology, and demography to structure understanding of growth, development, and aging.

In human contexts, life phases help organize knowledge about development, education, work, family life, and aging. Conventional phases include childhood, adolescence, young adulthood, adult life, middle age, and old age, though exact boundaries vary by culture, researcher, and policy. Life-course research emphasizes sequences of stages and the transitions between them—such as completing education, entering the labor market, forming partnerships, parenthood, and retirement—and the timing of these transitions, which can influence outcomes in health, employment, and well-being.

In biology, livsfaser refers to the stages of an organism’s life cycle, such as birth, growth, maturation, reproduction, and senescence. Some species exhibit metamorphosis or distinct developmental forms, while others follow more continuous growth. Studying life phases in biology aids understanding of development, ecology, and evolutionary strategies.

A key distinction is that life phases reflect both biological changes and social roles, whereas age is a numerical measure. Cultural norms, education systems, and policy environments shape how phases are defined and experienced, including when transitions occur or are supported by society.