It is estimated that
there are from 10-100 million species of organisms on
our planet. Despite 250 years of morphological work,
only 1.7 million of these species have been formally
described. The most serious weakness in sustaining current
approaches to the study of biological diversity arises
from the limited ability of humans to recognize and
recall morphological variation. As a result, few taxonomists
can reliably diagnose an assemblage of even 1000 species.
Given a universe of 10-100 million species, this implies
that a community of 10,000 to 100,000 taxonomists will
be required to simply sustain the ability to recognize
species, once we complete the task of their description.
It is this stark reality that provides the motivation
for a new approach to species recognition.
It is now clear that
microgenomic systems, which discriminate life's diversity
through the analysis of a small segment of the genome,
represent a promising approach to the diagnosis of biological
diversity. This concept has already gained broad acceptance
among those working on the least morphologically tractable
groups such as viruses, bacteria and protists. However,
it is increasingly recognized that the problems inherent
in morphological taxonomy are general enough to motivate
the diffusion of this approach to all life. In fact,
there are a growing number of cases in which DNA-based
systems have been applied to higher organisms.