About objective and subjective approach to recurrent complexes (for example, brachiopods and bivalves of the ilmen and bureg beds of the middle frasnian, ilmen glint)
- National Mineral Resources University (Mining University)
At the present time researchers are considering recurrence (return of fauna and flora after the return of physical and geographical conditions) one of the drawbacks of biostratigraphic methods. Comparing the features of complex brachiopods and pelecypods of the Ilmen and Bureg beds (middle Frasnian) Ilmen cliff, the author demonstrates the great complexity of the mechanism of recurrence, which depends not only on environmental but also on biological factors. Also a significant role in reducing the reliability of the analysis of systematic diversity of fossiles has biological and paleontological problem species diagnostics (distinction used by different researchers species criteria).