Am J Bot. 1998 May;85(5):637.
We explored the patterns of intra- and interpopulation variation in flower morphology of the red mangrove, Rhizophora mangle. Twelve populations in Mexico were studied: five from the Gulf of Mexico and the Caribbean Sea, and seven from the Pacific Coast. Six metric floral attributes were measured from a sample of 1370 flowers. Significant differences among populations were found for all six attributes. Because floral attributes were all correlated, scores derived from principal factor analysis were used to describe the variation in flower morphology. Two factors explained essentially all of the variance in flower morphology. Corolla and calyx size had a strong effect on factor 1, while gynoecium size had the higher effect on factor 2. Nested analyses of variance on the scores from both factors revealed significant differences among coasts, among populations within coasts, and among plants within populations. Nonetheless, this variation cannot be explained as a result of clinal variation, as indicated by a series of regression analyses. Cluster analysis (UPGMA) showed that a population from the Pacific coast was clustered together with those of the Atlantic, and the arrangement of populations within each coast showed no evident geographical pattern. We propose that frequent events of extinction and recolonization by a few individuals, followed by selfing, may produce differentiation among populations of red mangrove.
我们探讨了红树，Rhizophora mangle 的花形态的种内和种间变异模式。在墨西哥研究了 12 个种群：来自墨西哥湾和加勒比海的 5 个，以及来自太平洋海岸的 7 个。从 1370 朵花的样本中测量了六个度量花属性。所有六个属性在种群之间都存在显著差异。由于花属性全部相关，因此使用主因子分析得出的分数来描述花形态的变化。两个因子基本上解释了花形态的所有变化。花瓣和萼片的大小对因子 1 有强烈影响，而雌蕊的大小对因子 2 有更高的影响。两个因子的得分嵌套方差分析显示出海岸之间、海岸内种群之间和种群内植物之间存在显著差异。尽管如此，这种变异不能解释为梯度变异的结果，这表明一系列回归分析。聚类分析（UPGMA）表明，来自太平洋海岸的一个种群与大西洋的种群聚类在一起，每个海岸内的种群排列没有明显的地理模式。我们提出，少数个体的灭绝和再殖民事件频繁发生，随后是自交，可能导致红树种群之间的分化。
