Learning Objectives

7.2.1 Illustrate how the number of offspring may affect the size of those offspring.

7.2.2 Explain how providing care to offspring may compromise other functions in adults.

7.2.3 Understand that allocating energy and resources to reproduction may affect parental growth, survival, and future reproduction.

Organisms have limited amounts of energy and resources that can be invested in growth, reproduction, and defense. As discussed in Concept 6.3, trade-offs occur when organisms allocate their limited energy or other resources to one structure or function at the expense of others. As we'll see, trade-offs among life history traits are common.