Biotic transitions in global marine diversity

Area of Science:

• Paleontology
• Marine Biology
• Earth Science

Background:

• Long-term changes in marine life composition during the Phanerozoic have been attributed to biotic interactions or mass extinctions.
• Previous models proposed distinct mechanisms for background diversity changes versus mass extinction events.

Purpose of the Study:

• To investigate the underlying drivers of long-term marine biota transitions throughout the Phanerozoic.
• To reconcile the roles of biotic interactions, mass extinctions, and physical perturbations in shaping marine biodiversity.

Main Methods:

• Analysis of macroevolutionary processes across different time scales, including background and mass extinction periods.
• Examination of evidence for physical perturbations at various geographic scales influencing biotic composition.

Main Results:

• Macroevolutionary processes during non-extinction periods are not fundamentally different from those during mass extinctions.
• Physical perturbations across multiple scales were key factors in determining the long-term trajectory of Phanerozoic diversity.
• Biotic interactions and mass extinctions alone do not fully explain long-term biodiversity patterns.

Conclusions:

• The long-term evolution of marine biota is a product of integrated processes, where physical perturbations play a crucial role.
• A unified view of macroevolutionary dynamics, encompassing both background and extinction events, is supported by new evidence.
• Understanding Phanerozoic diversity requires considering the interplay of physical forces and biological responses over geologic time.