3. Aging Is the Ancestral Default, whereas Nonaging Is a Derived State

Aging does not require any additional forces, specialized genes, or specialized functions to occur. It is not an adaptation that emerged from a nonaging ancestor; nonaging (or negligible aging), where it exists, is the derived state and may revert back to aging. In this framework, aging is a default consequence of biological work performed under thermodynamic constraints: living systems must continuously use energy to maintain organization, but biological functions and maintenance systems (damage prevention and clearance) are almost always imperfect. Therefore, despite evolved countermeasures, the deleteriome tends to rise over time. This framing does not deny cell and organismal agency, goals, and regulation; it simply states that the baseline direction, absent perfect repair, reset, or replacement, is toward accumulation of deleterious changes. The practical implication is that there is no mysterious biological program that causes aging; instead, biological systems evolved functions that support fitness in the background of the aging process (3, 4, 6–8).