Are females maternal manipulators, Selfish mothers, or both? Insight from pythons

摘要

During reproduction, females often modify their behavior relative to the nonreproductive condition. These changes are frequently attributed to maternal efforts to optimize offspring development and survival (i.e., the maternal manipulation hypothesis). However, Schwarzkopf and Andrews (2012) recently challenged this concept as oversimplified, emphasizing that females should optimize their own lifetime fitness, and therefore maternal efforts may be directed at the female's future reproductive effort in addition, or even in contrast, to current reproductive effort. To provide insight into the relative importance of current versus future reproductive effort in shaping maternal behavior, we systematically explore a single study system - pythons. Pythons show distinct maternal behaviors during gravidity (modified basking effort), perioviposition (nest site selection), and postoviposition (egg brooding). By examining each component, we reveal that python maternal effort is predominantly aimed at current offspring. Yet, at times, females will make decisions that benefit their future reproductive potential at a cost to their current effort. Therefore, maternal behavior likely reflects a focused effort to maximize fitness through optimizing current reproductive investment, but such effort is not without consideration of future reproductive potential.