The structure of phylloclades and true leaves in Phyllocladus was investigated with emphasis on function, ecology and evolution. Only in the earliest ontogenetic stages are true, needle leaves developed. The earliest phylloclades comprise a fusion product of a shoot axis of the first order and its inserted leaves. Later, this is augmented by the expansion of axillary short shoots from the base of some of the fused leaves. Phylloclades of mature individuals are entire short shoot systems, including leaves and shoots, becoming fused with photosynthetic tissue. These phylloclades represent one of the adaptations for increasing functional photosynthetic area that are present in Podocarpaceae. Such adaptations were probably needed because Podocarpaceae are usually medium-sized trees faced with competition from the ever-expanding angiosperm forests at mid to high latitudes in the Southern Hemisphere from the Late Cretaceous, but especially during the Palaeocene–Eocene, when dense and diverse angiosperm-dominated rainforests were common. The data obtained from living species were compared to those from fossil material of Phyllocladus. Phyllocladus with fully developed phylloclades have been in place since at least the early Cenozoic.

中文翻译：

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毛竹科植物光合器官的进化及其生态意义

毛竹叶柄和真叶的结构研究重点是功能，生态和进化。只有在最早的个体发育阶段才是真实的，针叶发育。最早的叶螨包括第一级的芽轴与其插入的叶子的融合产物。后来，腋生短枝从一些融合叶的根部扩展而得到增强。成熟个体的叶螺是完整的短芽系统，包括叶和芽，与光合组织融合在一起。这些叶甲代表了增加对罗汉松的功能性光合面积的适应之一。可能需要这样的适应，因为罗汉松科通常是中等大小的树木，面临着白垩纪后期南半球中高纬度不断扩大的被子植物森林的竞争，特别是在古新世-始新世期间，被子植物密集而多样主导的雨林很普遍。比较了从生物物种获得的数据与从化石材料获得的数据Phyllocladus。Phyllocladus至少早新生代以来有充分发展phylloclades已全部到位。