Species, Taxonomy, and Systematics 425while at the same time keeping biological taxonomy as stable as possible.^2
Stepping back, in this chapter we have seen a variety of conceptual issues at
the forefront of biological taxonomy and systematics. Species may not be qualita-
tive kinds but historical entities defined by genealogy. The idea of single correct
classification of the organic world may need to be replaced with a more pluralistic
approach to classification. The Linnaean ranks that pervade biology may have no
basis in nature but are merely instruments for organizing life’s diversity. Other
radical changes in how we classify and bring order to the organic world may be
just around the corner. For example, life on this planet may not be a single ge-
nealogical tree, but a tangled bush [Doolittle, 1999]. If life is a tangled bush, then
hierarchical classifications may be the wrong way to represent life’s diversity. Bio-
logical systematics is rife with conceptual issues in need of philosophical analysis.
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1992.(^2) Wiley [1981] also suggests a revised Linnaean hiearchy, what he calls the “annotated Linnaean
hierarchy.” Wiley’s annotated Linnaean hierarchy is different than the revised Linnaean hierarchy
offered here. To cite one difference, Wiley’s revision does not divorce the activity of naming taxa
from the activity of classifying taxa. Thus, Wiley’s annotated Linnaean hierarchy does not
address or solve any of the naming problems mentioned in Section 4.2.