Systematics, Floral Structure and Reproductive Biology of Mid-Cretaceous Magnoliid Angiosperms

显花植物是最大的植物群， 被子植物约有50万种。 除了 被子植物种类繁多，经济价值巨大， 对人类的重要性。 被子植物也是许多植物的主要成分 或大多数陆地生态系统，并主宰所有非针叶 陆地生物群系 可以理解的是，植物学家对 在发展有关起源的模型和推论， 辐射这个非常重要的群体。 最近二 几十年的技术（分子系统学和分支系统学）已经 允许对地球上的生物进行严格的科学调查 有花植物的起源和系统发育问题 集团的模式。 因此， 被子植物基部的关系现在是可用的 树 被子植物的起源和最初的辐射是在 白垩纪;然而，白垩纪的化石记录是 相对贫穷。 起重机建议研究化石的多样性 白垩纪沉积物中的被子植物， 美国和葡萄牙。 这些样本包括花花粉 水果和种子，所有这些都是诊断实用， 了解和分类开花植物。 他打算 通过整合化石形式来探索它们之间的关系 进入当前的关系模型，并测试这些模型。 基于这些发现，他建议探索古生态学 以及最早期被子植物的授粉过程。 新模式 将酌情发展关系。 审查 已经收藏的标本将通过电子 和光学显微镜。 所描述的研究将对我们的研究产生有益的影响。 了解被子植物及其进化历史。 这反过来又会刺激更多的研究， 和支序分类法。

The flowering plants comprise the largest group of plants, Angiospermae with approximately 500,000 species. In addition to sheer diversity, the angiosperms are of tremendous economic importance to humans. Angiosperms are also major elements of many or most terrestrial ecosystems, and dominate all non-coniferous terrestrial biomes. Understandably, botanists have been interested in developing models and inferences concerning the origin and radiation of this highly significant group. Within the past two decades techniques (molecular systematics and cladistics) have become available to permit rigorous scientific inquiry into the problem of the origin of the flowering plants and phylogenetic models of the group. Accordingly hypotheses of phylogenetic relationships are now available for the base of the angiosperm tree. The origin and primary radiation of the angiosperms was in the Cretaceous; however, the fossil records from the Cretaceous are relatively poor. Crane proposes to examine the diversity of fossil angiosperms in Cretaceous deposits in what is now the eastern United States and Portugal. These samples include flowers, pollen, fruits, and seed, all of which are of diagnostic utility in understanding and classifying flowering plants. He intends to explore relationships among the fossil forms by integrating them into the current models of relationships and to test those models. Based on these findings, he proposes to explore the paleoecology and and pollination of the earliest angiosperms. New models of relationships will be developed as appropriate. Examination of the specimens, which are already in collections, will be via electron and light microscopy. The described research will have a salutary effect on our understanding of the angiosperms and their evolutionary history. This, in turn, should stimulate additional research using molecular and cladistic approaches.