Dynamic Demography of Ant- and Bird-Dispersed Herbs: Divergent Responses to Tropical Forest Gap-Phase Regeneration

种子分布、植物种群和环境的时空异质性，通过它们的相互作用，决定了生物所居住的生态和进化景观。提出了一个简单的假设，以一种新的方式定量地将进化生态学的这三个领域联系起来。一个植物种群动态和森林动态模型预测，在间隙期更新过程中，抗分散物种的人口变化速度比鸟类分散物种慢。在一个林下草本植物科中，通过比较间隙期再生过程中种群分布、光照环境和散布物组合的变化，对这些不同的种子传播综合征（局部传播与远距离传播）的选择进行研究。初步资料证实，哥斯达黎加马兰科植物为研究提供了极好的机会。森林光照生境中植物的静态分布与扩散综合征显著相关，表明它们在间隙期更新过程中对中间生境的动态响应存在差异。

Seed distribution, plant demography and spatiotempporal heterogeneity ofthe environment, by their interactions, determine the ecological and evolutionary landscape inhabited by an organism. A simple hypothesis that quantitatively links these three areas of evolutionary ecology in a new way is proposed. A model of plant population dynamics and forest dynamics predicts that ant-dispersed species will be characterized by a slower rate of demographic change during gap-phase regeneration than bird-dispersed species. Selection for these divergent seed dispersal syndromes (local dispersal vs. long-distance dispersal) will be investigated in a family of understory herbs by comparing changes in demography, light environments and disperser assemblages during gap-phase regeneration. Preliminary data confirmed that the Costa Rican Marantaceae provide an excellent opportunity for the study. The static distribution of plants in forest light habitats was significantly associated with dispersal syndrome, suggesting differences in their dynamic response to intermediate habitats during gap-phase regeneration.