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通过整理和分析木兰科植物的化石记录发现 :不论是植物大化石还是花粉 ,迄今为止在白垩纪以前地层中尚无可靠的记录。自白垩纪以来 ,木兰科的许多种广泛发生于北半球 ,如亚洲、欧洲及北美等地 ,但非洲和大洋洲至今尚未发现木兰科的化石记录。该科最早的化石记录为中国东北延吉地区早白垩世大拉子组的喙柱始木兰Archimagnoliarostrato stylosaTaoetZhang。根据现有化石记录 ,并结合木兰科现代植物的地理分布 ,推测 :1)木兰科的起源时间不迟于早白垩世Aptian Albian期 ;2 )木兰科起源地点可能是东亚 ,后来经过欧洲进入北美 ,再从北美迁移到达南美洲 ;3)在地质历史时期 ,木兰属的出现比鹅掌楸属早 ,从而支持根据形态学与分子系统学研究得出的木兰属较鹅掌楸属原始的结论
Through the collation and analysis of the fossil records of Magnoliaceae plants, it has been found that there has been no reliable record so far in the strata before the Cretaceous, no matter whether it is a large plant fossil or a pollen. Since the Cretaceous, many species of Magnoliaceae occur widely in the northern hemisphere, such as Asia, Europe and North America, but so far no records of magnolias have been found in Africa and Oceania. The earliest fossil record of this section is Archimagnoliarostrato stylosa Taoita Zhang in the Early Cretaceous Dalazi Formation in the Yanji area, northeastern China. Based on the existing records of fossils and the geographical distribution of modern plants in Magnoliaceae, it is speculated that: 1) the origin of Magnoliaceae is not later than that of the Early Cretaceous Aptian Albian period; 2) the origins of Magnoliaceae may be East Asia, and then enter North America through Europe , And then migrated from North America to South America; 3) Magnolia appeared earlier than Liriodendron in geological history, thus supporting the original conclusion that Magnoliaceae was originated from the morphological and molecular systematics studies