Of all the biochemical inventions in the history of life,photosynthesis is surely one of the grandest, since the production of oxygen as a waste product resulted from the photosynthesis also profoundly changed the composition of the world's oceans,continents and atmosphere.However,the definitive evidence of the origin and evolution of photosynthesis such as the essential biological process,i.e.the nature of the earliest photosyn-thetic organisms as well as the problem dealing with how photosynthetic organisms obtain their photosynthetic ap-paratus and so on,may be lost forever.Thus,studies on the origin and evolution of photosynthesis became an important and enchanting scientific theme.Stromatolites may be Earth's oldest macroscopic fossils;however,it remains controversy what,if any,biological processes are recorded in their morphology.Interestingly and en-chantingly,two aspects of innovating cognitions have been obtained from the study on the biological process of stromatolites:(1)a qualitative similarity between conical stromatolites and some modern microbial mats suggests a photosynthetic origin for ancient stromatolites;(2)conical stromatolites are thought to be robust indicators of the presence of photosynthetic microbes in aquatic environments as early as 3.5 billion years ago,and the cya-nobacterial production of oxygen in the tips of modern conical aggregates implies not only that cyanobacteria built conical stromatolites but also that oxygen bubbles resulted from the photosynthesis may constrain the timing of the evolution of oxygenic photosynthesis.Therefore,many innovating cognitions obtained from studies on the morphological nature and its photosynthetic signals of the conical stromatolite,not only delegate an important ad-vancement on the study of stromatolites but also become a typical paradigm to interpret the biological process from sedimentological feature.Ultimately,it is meaningful to trace this aspect of studies for the further under-standing of both the sedimentological feature and the biological nature of stromatolites.%在生命历史长河的所有生物化学创造中，光合作用无疑是最伟大的创造之一；因为在光合作用过程中，作为废料的氧气生产作用，确实明显改变了地球海洋、大陆和大气圈的构成。但是，光合作用起源与进化的确切证据，包括光合作用的基本生物学过程，如地球早期光合作用生物的属性、光合作用生物如何获取光合作用装置等，可能已经消失在时间的长河之中；因此，光合作用起源与进化就成为一个引人入胜的重大科学命题。叠层石可能是地球上最为古老的宏观化石，其形态学特征究竟记录了什么样的微生物过程，还存在很多争论。在这个方面的研究中，科学家们获取了两个最为引人注目的创新性认识：（1）锥状叠层石与一些现代微生物席之间的定性化的相似性，表明了古代锥状叠层石的光合作用成因；（2）早在35亿年的水生环境之中，锥状叠层石被认为是在光合作用微生物存在的坚实标志，而且现代锥状聚合体尖端氧气的蓝细菌生产作用较为充分地表明，蓝细菌不但建造了锥状叠层石，而且光合作用产生的氧气气泡可能包含着生氧光合作用进化的时间进程。因此，锥状叠层石的形态学属性及其所蕴含的光合作用信号的研究以及其所取得的创新性认识，不但代表了叠层石研究的一个重要进展，而且成为从沉积学特征去阐释生物学过程的一个典型范例；进行这方面的研究，对深入了解叠层石的沉积学特征和生物学属性具有重要的科学意义。
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