Cladograms, phylogenies and the veracity of the conodont fossil record

Traditionally, conodont intrarelationships have been reconstructed following the evolutionary palaeontology paradigm, which lacks a formal methodology, renders hypotheses unrepeatable and takes little account of the imperfect nature of the fossil record. Cladistics provides a prescriptive approach to phylogeny reconstruction and, it is argued, a rigorous method of character analysis that is not incompatible with the aims of evolutionary palaeontology. To demonstrate this, we use the Silurian family Kockelellidae as an example of how cladistics can be used to reconstruct relative relationships, and how such hypotheses can be converted to phylogenies. We follow traditional, cladistic approaches to assessing the completeness of the fossil record and find that failure to conduct this within a milieu of absolute, rather than merely relative, relationships leads to spurious inferences of gaps in the fossil record. This appears to be a problem that is widespread in theory, but peculiar to spec...

传统上，牙形石（conodont）的类群内部亲缘关系多依据进化古生物学（evolutionary palaeontology）范式开展重建，此类方法缺乏正式的研究方法论，致使所提出的假说无法复现，且极少顾及化石记录（fossil record）的不完备特性。分支系统学（Cladistics）可为系统发育重建（phylogeny reconstruction）提供规范性研究路径，且据相关论证，其严谨的性状分析（character analysis）方法与进化古生物学的研究目标并无冲突。为验证这一论点，本文以志留纪（Silurian）的科克奈尔牙形石科（Kockelellidae）为例，演示如何借助分支系统学重建类群的相对亲缘关系，以及如何将此类假说转化为系统发育树。我们沿用传统的分支系统学方法评估化石记录的完整性，研究发现，若未在绝对而非仅相对的亲缘关系框架内开展此类研究，将会得出关于化石记录缺失的虚假推断。该问题在理论层面似乎普遍存在，但却特指于……