A life-cycle refers to the temporally organised trajectory through which a living system persists across changing forms, capacities, and conditions.
In conventional biology, life-cycles are often presented as ordered sequences of stages such as birth, growth, reproduction, and death. APS instead interprets life-cycles as dynamically organised patterns of continuity extending across time and scale.
A life-cycle is not merely a chronological sequence.
It is an organised trajectory through which viability-oriented systems continually reorganise themselves while preserving continuity across changing developmental, physiological, behavioural, ecological, and reproductive conditions.
APS therefore emphasises that life-cycles are fundamentally processual.
The identity of a biological system is not tied to a single static state within the life-cycle, but to the continuity of organisational persistence across ongoing transformation.
Life-cycles may involve:
- developmental transitions,
- metamorphosis,
- behavioural reorganisation,
- ecological role shifts,
- reproductive transformation,
- ageing,
- dormancy,
- migration,
- and senescence.
What unifies these diverse phenomena is the preservation of viability-oriented continuity across changing organisational conditions.
APS also emphasises that life-cycles are scale-sensitive.
Different organisational scales may possess partially overlapping or nested life-cycles. Cells, organisms, colonies, populations, and ecosystems may exhibit distinct but interconnected temporal trajectories.
Life-cycles therefore reveal that biological continuity is historically extended and organisationally distributed.
APS distinguishes life-cycles from simple stage models.
Stage-based descriptions often imply discrete transitions between static conditions. APS instead interprets life-cycles as continuous reorganisational processes in which boundaries between phases are often gradual, context-dependent, and dynamically regulated.
Life-cycles also differ from mere temporal duration.
A life-cycle concerns the organised transformation of viability-oriented continuity, not simply the amount of time a system exists.
Importantly, APS interprets reproduction as embedded within broader life-cycle organisation rather than as an isolated event.
Reproductive processes contribute to the continuity of organised persistence across generations and ecological contexts.
Life-cycles therefore demonstrate one of the core principles of APS:
living systems persist not by remaining unchanged, but through temporally organised reorganisation across the history of their existence.