SEED SEEDLING CONFLICTS, HABITAT CHOICE, AND PATTERNS OF PLANT RECRUITMENT

The ecological forces determining where within a landscape plants recr uit and grow has been termed proximal habitat choice. Habitat choice i s imposed first by a heterogeneous pattern of seed dispersal across th e patches that make up the landscape and second by environmental varia tion that favors plant survival in some patches more than in others. S eed-seedling conflicts can occur during both of these phases of habita t choice if conditions or traits that are favorable for seeds are unfa vorable for seedlings. During the dispersal phase, smaller seeds may h ave a greater probability of dispersal than larger seeds, and thus a g reater probability of escape from predation, but they contain fewer re serves for support of the establishing seedling. After dispersal, envi ronmental characteristics of a given patch type that lead to dispropor tionately high seed survival may lead to disproportionately low seedli ng survival. Considering three hypothetical landscapes, each composed of five patch types, I demonstrate that seed-seedling conflicts can ha ve a major impact on both the overall quantity of recruitment at the l andscape level and on the distribution of recruitment among patches. A vailable empirical evidence suggests these conflicts may be widespread in natural systems. Given their potential importance and extent, seed -seedling conflicts may play a previously unrecognized role in habitat choice.