Data from: Experimentally decoupling reproductive investment from energy storage to test the functional basis of a life-history tradeoff

The ubiquitous life-history trade-off between reproduction and survival
has long been hypothesized to reflect underlying energy-allocation
trade-offs between reproductive investment and processes related to
self-maintenance. Although recent work has questioned whether
energy-allocation models provide sufficient explanations for the survival
cost of reproduction, direct tests of this hypothesis are rare, especially
in wild populations. This hypothesis was tested in a wild population of
brown anole lizards (Anolis sagrei) using a two-step experiment. First,
stepwise variation in reproductive investment was created using unilateral
and bilateral ovariectomy (OVX) along with intact (SHAM) control. Next,
this manipulation was decoupled from its downstream effects on energy
storage by surgically ablating the abdominal fat stores from half of the
females in each reproductive treatment. As predicted, unilateral OVX
(intermediate reproductive investment) induced levels of growth, body
condition, fat storage and breeding-season survival that were intermediate
between the high levels of bilateral OVX (no reproductive investment) and
the low levels of SHAM (full reproductive investment). Ablation of
abdominal fat bodies had a strong and persistent effect on energy stores,
but it did not influence post-breeding survival in any of the three
reproductive treatments. This suggests that the energetic savings of
reduced reproductive investment do not directly enhance post-breeding
survival, with the caveat that only one aspect of energy storage was
manipulated and OVX itself had no overall effect on post-breeding
survival. This study supports the emerging view that simple
energy-allocation models may often be insufficient as explanations for the
life-history trade-off between reproduction and survival.