传统上,风媒传粉被看成是这样的繁殖过程:其特征就是由一些随即事件的发生,在这些随机事件里,风的反复无常被大量的产生花粉所补偿,以至于新种子的最终产生被保证了,其代价是产生远远多于实际使用量的花粉。
87. Because the potential hazards pollen grains are subject to as they are transported over long distances are enormous,wind pollinated plants have,in the view above,compensated for the ensuing loss of pollen through happenstance by virtue of producing an amount of pollen that is one to three orders of magnitude greater than the amount produced by species pollinated by insects.
由于花粉粒在其长距离的运输过程中所要面临的潜在危险是巨大的,按上述观点来看,由风授粉的植物补偿了通过偶发事件而伴随造成的花粉损失。其途径是,制造出大于昆虫授粉的植物种类所产生的花粉量的一至三个数量级的花粉量。
88. For example,the spiral arrangement of scale-bract complexes on ovule-bearing pine cones,where the female reproductive organs of conifers are located,is important to the production of airflow patterns that spiral over the cones surfaces,thereby passing airborne pollen from one scale to the next.
例如,带有胚珠的松球的鳞苞综合体的螺旋状安排,亦即松柏目植物雌性殖器官的所在位置,对于气流模式的形成与产生殊为重要,而这些气流模式在松球的表现盘旋上升,从而把在空气中飞行的花粉从一个鳞苞传播至下一个鳞苞。
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