生活在这个世界上的所有物种、属、科、目，以及更高级阶元，在它们各自所属的属、科、目等范围内，都有一个共同祖先。本项目研究的科学意义在于从rDNA大亚基全长序列中，进而从rDNA（小亚基，ITS1,5.8S,ITS2,大亚基）全长序列中探明石耳目、科、属三个等级阶元的共祖基因序列及表型综合性状，从而使石耳目、科、属三个等级阶元可见的表型和基因型综合性状均以附有图表的文字展现出来。将基因信息添加到分类单元的描述中，对于分类学而言是一个极大的创新；本研究将为使整个生物各级阶元的共祖基因性状由未知变为可知的可行性提供探索性前期研究。

The innumeriable species, genera, families, orders, and other higher categories, with which this world is peopled, are all descended.This project will be carried out in order to search the gene sequences of the common descent from the full-length LSU rDNA as well as the full-length rDNA. And we will use these gene sequences together with the comprehensive phenotypic characters to delimit and describe the genera, families, and order of the Umbilicariales.It is a great innovation in taxonomy that the gene information are appended in the description of taxa; and this project will explore the posibility whether the common descent gene sequences in different taxa can be distinguished.