This website is designed to explore the science of biostratigraphy, not to evaluate evolutionary theories. However, a discussion on these theories is warranted. It is the irreversible direction of evolution (except for isolated cases of heterochony) which validates this science. Many biostratigraphic correlations have been made without paying proper attention to evolutionary theories. Many of these interpretations are now being questioned as new theories are accepted and applied.
Punctuated equilibria and allopatrick speciation introduce the diachronus problem to biostatigraphy. A problem which until recently (1970's) was not thought to influence biostratigraphy.
The understanding of evolutionary theories is the understanding of the basis upon which biostratigraphy is constructed. The advanced understanding and application of these theories, as well as identifying their characteristics and effects, satisfy the requirements needed for creating a definitive and holistic biostratigraphic correlation.