Schneider Dietrich, Wink Michael, Sporer Frank, Lounibos Philip
Max-Planck-Institut, Seewiesen/Starnberg, Germany.
Naturwissenschaften. 2002 Jul;89(7):281-94. doi: 10.1007/s00114-002-0330-2.
Palaeobiological evidence indicates that gymnosperms were wind-pollinated and that insect pollination began in angiosperms in the Lower Cretaceous (ca. 135 mya) leading to close associations between higher plants and their pollinators. Cycads, which were widespread and pervasive throughout the Mesozoic (250-65 mya) are among the most primitive living seed-plants found today. Because pollination by beetles and by thrips has now been detected in several modern cycads, it is attractive to speculate that some insects and cycads had already developed similar mutualistic interactions in the Triassic (250-205 mya), long before the advent of angiosperms. We also draw attention to another key factor in this insect-plant relationship, namely secondary, defensive plant substances which must always have controlled interspecific interactions. Cycads mainly produce toxic azoglucosides and neurotoxic non-protein amino acids (e.g. BMAA), which apparently are crucial elements in the development and maintenance of mutualism (pollination) and parasitism (herbivory) by cycad-linked herbivores. We now add new results on the uptake and storage of the main toxin, cycasin, of the Mexican cycad Zamia furfuracea by its pollinator, the weevil Rhopalotria mollis, and by a specialist herbivore of Zamia integrifolia, the aposematic Atala butterfly Eumaeus atala.
古生物学证据表明,裸子植物是风媒传粉的,而昆虫传粉始于下白垩纪(约1.35亿年前)的被子植物,这导致了高等植物与其传粉者之间的紧密联系。苏铁在中生代(2.5亿至6500万年前)广泛分布且无处不在,是现今发现的最原始的现存种子植物之一。由于现已在几种现代苏铁中检测到甲虫和蓟马传粉的情况,因此推测在被子植物出现之前很久的三叠纪(2.5亿至2.05亿年前),一些昆虫和苏铁就已经形成了类似的互利共生关系,这颇具吸引力。我们还提请注意这种昆虫与植物关系中的另一个关键因素,即植物的次生防御物质,它必定一直在控制着种间相互作用。苏铁主要产生有毒的氮杂葡萄糖苷和具有神经毒性的非蛋白质氨基酸(如β-甲氨基-L-丙氨酸),这些显然是苏铁相关食草动物在互利共生(传粉)和寄生(食草)关系的发展与维持中的关键要素。我们现在补充了关于墨西哥苏铁泽米铁的主要毒素苏铁苷被其传粉者象鼻虫软象鼻虫以及泽米铁的一种专门食草动物、具有警戒色的阿塔拉蝴蝶优红蛱蝶摄取和储存的新结果。