A tectonically driven 60 million-year biogeochemical redox cycle paces marine biodiversity

The fossil record shows a prominent 60 million-year biodiversity cycle
during the Phanerozoic Eon, the origin of which is still unknown. Here we
use time-series analysis and correlation of empirical and model datasets
of Earth’s interior and surficial processes to demonstrate that this cycle
is a pervasive feature in marine animal genus-level diversity data that
dominates in the Paleozoic Era. Our results suggest that extinctions are
likely the primary driver of this observed cyclicity. We detected a
correlatable 60 million-year cyclicity in global tectonics, and in marine
87Sr/86Sr and δ34S isotopes, all of which are dominant in the Paleozoic.
We conclude that continental weathering driven by global tectonic
degassing and building of continental arcs may have in turn controlled
paleo-seawater redox cycling during the Paleozoic when oceans were likely
less saturated with respect to oxygen. In particular, we suggest that the
60 million-year fluctuations in biotic diversity are responses of shallow
marine habitats to the combined effects of continental weathering and
redox cycling, under global tectonic control.