Application of PCR: Organismal and Population Biology

sive analysis of gene structure from a limited number of species, primarily humans, mice, fruit flies, yeast, and the bacterium Escherichia coli. The powerful new molecular biological methods have also led to major discoveries in population biology and the study of organismal evolution. Among the many achievements are a better understanding of the evolutionary relationships among the major groups of microorganisms (Woese 1987) and the discovery that apes and humans had a common ancestor as recently as 5 million years ago (Wilson et al. 1989). Despite the profound nature of such discoveries, little data have been generated by molecular biological methods when the world's total biota is considered. Only a small number of individuals and species have been