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The second classification principle of organisms is the lineage classification principle aiming at establishing evolutionary lineage. The classification method following this principle is called lineage classification. The representative of pedigree classification is "branch systematics". It advocates that the branches in evolution should be taken as the criteria for identifying and distinguishing classification units and the basis for determining the pedigree relationship of each classification unit. The so-called co-ancestral proximity (similar to a group of people being a grandfather) is used to measure the genetic relationship between different taxa and determine their position in the pedigree. The classification system finally established is an evolutionary pedigree reflecting the history of phylogeny, which is a deeper description of biological relationship. In other words, the basic principle of pedigree classification is that the classification system conforms to the evolutionary pedigree. Pedigree classification is only applicable to organisms and cannot be used for abiotic classification.Then study four situations in Android event distribution flow chart:二十世纪三十年代末，名动华北的京剧戏班“盛家班”与悍匪蒋有财结下了梁子，在冲突中头牌武生盛忠豪的父亲和恩师皆惨死。父亲临终前逼迫盛忠豪立下毒誓不能复仇，盛忍痛带着师弟文立轩和师妹甄玉环逃往天津。途中几人被溃兵冲散，为了掩护同门盛忠豪被抓，落入日军劳工营，在此过程中盛忠豪杀死汉奸替师叔报了仇，也因此错失了与师妹甄玉环重逢的机会，深深相爱的一对同门恋人从此天各一方。多年后，师兄妹三人战地相逢，百感交集。盛忠豪终于融入革命洪流，龙家集抗日自卫军被正式改编为八路军独立营，盛忠豪任营长，文立轩任指导员，兄弟二人再度并肩作战，最终他们全歼武藤雄一部。8. If the screen remains black, congratulations, it's done! Your iPhone7Plus has entered DFU mode.3. Take your above three certificates plus graduation certificate, ID card and physical examination, and you can sign up for the lecture-that is, "lecture".我不敢让小鱼儿去你们家，你爹娘整天都忙正事，可不敢烦他们。听了杜松的话，他放下筷子，从袖中扯出条帕子擦擦嘴，问道：跟我比，杜大哥不嫌丢人？杜松郁闷地问道：跟你比怎么就丢人了？众人也都笑问缘故。