ABSTRACT
In describing a lineage of evolving organisms in taxonomic language according to the accepted Linnaean method, the boundaries that must be placed between taxa may be either real or artificial. This chapter examines the methods used in the evaluation: morphological divergence, and rate of evolution. It considers the two subjects which are made primarily in relation to the examination of an evolving lineage rather than to the morphological relationships between two lineages. Quantitative assessment of morphological change in populations involves the selection and isolation of taxonomic characters which can be treated in a quantitative form. Such selection involves an understanding of the relationship between structure and function, and between function and behavior. The chapter is concerned with what Simpson has termed “temporal morphologic rate” which is the rate of morphological change with time. It suggests certain techniques which might be used for the elucidation of hominid taxonomy.
