Causes and Prime Causes of Mass Biotic Extinctions in the Phanerozoic

摘要

Changes of various scales in biotic communities determined by environmental reorganizations provide grounds for defining geological periods. Transitions between geological periods are marked by partial extinctions of some organisms and the appearance of new taxa. Significant (catastrophic) extinctions that resulted in the disappearance of most species (>75%) during geologically short periods are referred to "great extinction events." The causes of mass biotic extinctions become particularly evident from the analysis precisely of such events. The Phanerozoic Eon was marked by five great extinctions.