Rodríguez-Gironés Miguel A, Santamaría Luis
Estación Experimental de Zonas Aridas, Consejo Superior de Investigaciones Científicas (CSIC), General Segura 1, 04001 Almería, Spain.
Am Nat. 2007 Sep;170(3):455-64. doi: 10.1086/520121. Epub 2007 Jul 16.
It is normally thought that deep corolla tubes evolve when the plant's successful reproduction is contingent on having a corolla tube longer than the tongue of the flower's pollinators. Combining optimal foraging theory and quantitative genetics in a spatially explicit, individual-based model, we show that flowers with long corolla tubes can alternatively evolve because they promote resource partitioning among nectar feeders and increase the probability of conspecific pollen transfer. When there is competition for resources, long-tongued flower visitors feed preferentially at deep flowers and short-tongued visitors at shallow flowers. Both plant species thus benefit when the depths of their corollas are so different that each flower visitor specializes on one species. Resource competition can promote the evolution of deep corollas despite the presence of significant amounts of noise, such as deviations from optimal foraging behavior due to perceptual errors or temporal fluctuations in the relative abundance of competing pollinator species. Our results can explain the evolution of long corollas in a number of systems that do not conform to the traditional view.
通常认为，当植物的成功繁殖取决于花冠管长度超过其传粉者的口器长度时，深花冠管就会进化。我们通过在一个基于个体的空间明确模型中结合最优觅食理论和数量遗传学，表明长花冠管的花朵也能够进化，因为它们促进了花蜜取食者之间的资源分配，并增加了同种花粉传递的概率。当存在资源竞争时，长口器的访花者优先取食深花冠的花朵，短口器的访花者取食浅花冠的花朵。因此，当两种植物花冠深度差异足够大，使得每种访花者都专门取食一种植物的花朵时，这两种植物都会受益。尽管存在大量干扰因素，如由于感知误差或竞争传粉者物种相对丰度的时间波动而导致的偏离最优觅食行为，资源竞争仍能促进深花冠的进化。我们的结果可以解释许多不符合传统观点的系统中长花冠的进化。
