The geologic time scale is often subdivided on the basis of ____.
A) the appearance of different radioactive isotopes in different strata
B) levels of background extinction
C) periods of mass extinction
D) the appearance of new species
E) climate change

Question

The geologic time scale is often subdivided on the basis of ____.
A) ​the appearance of different radioactive isotopes in different strata
B) ​levels of background extinction
C) ​periods of mass extinction
D) ​the appearance of new species
E) ​climate change

Quizplus · Accepted Answer

The geologic time scale is subdivided based on periods of mass extinction, which mark significant changes in Earth's history and the transition between different eras and periods.

The Geologic Time Scale Is Often Subdivided on the Basis