I believe that Malcolm McMahon has clearly expressed the essential
evolutionary rationale for the "Hayflick" limit, that is the finite
proliferative capacity of most somatic cell types. Primarily,
it is a protection against cancer, because a cell which has been
transformed to morphological or metastatic malignancy, but still has
a finite lifespan will in many circumstances not kill the host.
S.Shall at sussex.central.ac.uk