“Density-independent” for in r-selected species, mortality is. This relationship follows from the ecological mechanism represented by the terms in the item, not merely from an association between their names. Life-history traits reflect allocation among growth, maintenance, survival, and reproduction. Energy invested in many offspring cannot simultaneously be invested in large offspring, prolonged care, or future breeding, creating measurable trade-offs. The remaining alternatives—“Density-dependent”, “Late-life driven”, “Genetically fixed”—refer to different states, processes, or scales and t
Ref:
Ecology: Concepts and Applications, Molles, 9th Ed., Ch. 12