Knox EB
Herbarium and Department of Biology, University of Michigan, Ann Arbor, MI 48109-1048, U.S.A.
Biol J Linn Soc Lond. 1998 Jan;63(1):1-49. doi: 10.1111/j.1095-8312.1998.tb01637.x.
A hierarchy is an abstract organizational model of inter-level relationships among entities. When isomorphic with nature, hierarchies are useful for organizing and manipulating our knowledge. Hierarchies have been used in biological systematics to represent several distinct, but interrelated, facets of the evolution of life with different organizational properties, and these distinctions have been confused by the rubric «the hierarchy of life». Evolution, as descent with modification, is inherently dualistic. The organizational structure of a hierarchy can be used to represent dualistic properties as inter-level relationships. Cladistics is monistic, with a singular focus on patterns of descent. Descent has conceptual priority over modification, but the organizational relationship is not exclusive. «Cladistic classification» is an oxymoron because cladistics lacks the class concepts needed to construct a classification, a point recognized by those who suggest abandoning Linnaean classification in favour of a newly devised monophyletic systematization. Cladistic analysis of descent can be supplemented with an analysis of modification that provides the class concepts needed to construct an evolutionary/phylogenetic classification. When a strong monophyletic pattern of modification is detected (in addition to its monophyletic pattern of descent), the criterion of subsequent modification provides the basis for formally recognizing a certain monophyletic group at a given rank, as opposed to a group that is one node more inclusive or one node less. The criterion of subsequent modification also permits detection of strong paraphyletic patterns of modification, when they exist. By setting standards of evidence needed to recognize paraphyletic groups, one concomitantly strengthens the basis for formally recognizing selective monophyletic groups.Copyright 1998 The Linnean Society of London
层次体系是实体之间层次关系的一种抽象组织模型。当与自然同构时，层次体系有助于组织和运用我们的知识。层次体系已被用于生物系统学，以呈现生命演化中几个不同但相互关联的方面，这些方面具有不同的组织特性，而“生命层次体系”这一表述却将这些区别弄得模糊不清。进化，作为有修饰的传代，本质上是二元性的。层次体系的组织结构可用于将二元性属性表示为层次间的关系。分支系统学是一元性的，只专注于传代模式。传代在概念上优先于修饰，但这种组织关系并非排他性的。“分支分类”是一种矛盾表述，因为分支系统学缺乏构建分类所需的类概念，那些建议摒弃林奈分类法而支持新设计的单系系统学的人也认识到了这一点。对传代的分支系统学分析可以辅以对修饰的分析，后者提供构建进化/系统发育分类所需的类概念。当检测到强烈的单系修饰模式（除了其单系传代模式）时，后续修饰的标准为正式识别给定等级的某个单系类群提供了基础，这与一个包容性多一个节点或少一个节点的类群形成对比。后续修饰的标准也允许在存在强烈并系修饰模式时对其进行检测。通过设定识别并系类群所需的证据标准，同时也加强了正式识别选择性单系类群的基础。版权所有1998年伦敦林奈学会
