The unclear concept of “species” as a category of biological research is
discussed as specifically applied to human evolution. The concept is a rigid 18th century
pre-evolutionary category that complicates biological thinking about dynamic
processes of evolution. Currently, there are 23 defintions of “species” used by
biologists. With the above in mind, a discussion of the hominin fossil record is
presented in terms of the number of purported “species” into which the fossils can be
straightjacketed. The conclusion is that the simplest hypothesis, that of a single human
species being present at any point in time during the last few million years, cannot be
reliably falsified with the evidence currently available.
Keywords: Ancient DNA, Darwin, Diversity, Linnaeus, Mayr, Palaeoanthropology,
Species definition, Variability.
