A cohort is essential for constructing:
“Survivorship curve” for a cohort is essential for constructing. 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—“Phylogenetic tree”, “Age pyramid”, “Food web”—refer to different states, processes, or scales and therefore do
Ref: Ecology: Concepts and Applications, Molles, 9th Ed., Ch. 10