REU: Pollen Morphology and Evolution in the Proteaceae

分布在澳大利亚、南非和南美洲的南半球植物变形科的分类主要基于花和果实的形态特征。目前已知67属1450种。为了用新的数据检验这些植物的分类，德保罗大学的西尔维娅·费尔博士正在用光学和电子显微镜研究代表性样品的花粉结构和雕刻。利用冷冻切片和透射电镜对花粉壁表面和壁层的精细细节进行了分析，以获得有用的信息，以确定不同属花粉的等效特征进行比较。花粉壁结构和雕刻模式在密切相关的类群中是相似的，并表现出可识别的进化变化趋势。Feuer博士所描述的这一科花粉颗粒之间的差异，也将有助于确定分散的化石花粉的正确分类关系。被认为来自变形科的谷物出现在北半球的沉积物中，远远超出了该家族目前的地理范围。准确确定它们的分类地位是解决这些植物的历史生物地理学问题和进一步分析气候和其他因素对植物分布的控制的先决条件。

The taxonomic classification of the southern hemisphere plant family Proteaceae, distributed in Australia, South Africa, and South America, is based largely upon morphological features of the flowers and fruits. About 67 genera and 1450 species are currently recognized. To test the classification of these plants with new data, Dr. Sylvia Feuer of DePaul University is investigating the pollen structure and sculpturing of representative samples using light- and electron-microscopy. Fine details of the pollen wall surface and wall layering are being analyzed with cryosections and with transmission electron microscopy, to obtain information useful in determining equivalent features for comparison among pollen from different genera. Patterns of pollen wall structure and sculpture are expected to be similar among closely related groups of taxa, and to exhibit recognizable trends of evolutionary change. Differences among pollen grains of this family that are being described by Dr. Feuer will also allow determination of the correct taxonomic association of dispersed fossil pollens. Grains thought to be from Proteaceae occur in deposits in the northern hemisphere, far outside the current geographic range of the family. Accurate determination of their taxonomic status is prerequisite to resolution of the historical biogeography of these plants and to further analysis of climatic and other controls on plant distribution.