Lottery coexistence models extended to plants with disjoint generations

Abstract

Abstract. Neither conventional niche theory nor current lottery models offer a satisfactory theoretical scope for modelling coexistence of species with disjoint generations. South‐African fynbos and Australian kwongan include many species which are killed by, and recruit only after, fire. We propose a density‐dependent lottery model which accommodates the unusual demographics of these species. We show that coexistence requires density dependence in recruitment. The result applies to a wider class of populations than the one considered here. It is applied to non‐resprouting species in fynbos and kwongan. We show that the lottery assumption of recruitment in proportion to propagules is often satisfied, while the production of such propagules is often density‐dependent, and we discuss some evidence of mechanisms whereby this may occur.