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Trade?off between fecundity and survival generates stabilizing selection on gall size

ABSTRACT: Abstract Complex interactions within multitrophic communities are fundamental to the evolution of individual species that reside within them. One common outcome of species interactions are fitness trade?offs, where traits adaptive in some circumstances are maladaptive in others. Here, we identify a fitness trade?off between fecundity and survival in the cynipid wasp Callirhytis quercusbatatoides that induces multichambered galls on the stem of its host plant Quercus virginiana. We first quantified this trade?off in natural populations by documenting two relationships: a positive association between the trait gall size and fecundity, as larger galls contain more offspring, and a negative association between gall size and survival, as larger galls are attacked by birds at a higher rate. Next, we performed a field?based experimental evolution study where birds were excluded from the entire canopy of 11 large host trees for five years. As a result of the five?year release from avian predators, we observed a significant shift to larger galls per tree. Overall, our study demonstrates how two opposing forces of selection can generate stabilizing selection on a critical phenotypic trait in wild populations, and how traits can evolve rapidly in the predicted direction when conditions change. Complex interactions within multitrophic communities can result in fitness trade?offs for individual species, where traits adaptive in some circumstances are maladaptive in others. In this paper, we identify a fitness trade?off in the cynipid wasp Callirhytis quercusbatatoides, which induces multichambered galls on the stem of its host plant Quercus virginiana. We find a positive association between the trait “gall size” and fecundity, where larger galls contain more offspring, and a negative association between gall size and survival, where larger galls are attacked by birds at a higher rate. We then use a field?based experimental evolution study where birds were excluded from host trees for five years and observe a significant shift to larger galls per tree in the direction predicted by natural selection.

SUBMITTER: Weaver A

PROVIDER: S-EPMC7520187 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Trade?off between fecundity and survival generates stabilizing selection on gall size

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