Until Now
BiologyEnvironment

Plankton rebuild the ocean

From a handful of surviving species, calcareous plankton re-diversify and restart the carbon pump.

When
Duration
2 million years
Known to
± 500 thousand years
Era
Paleocene, Cenozoic

Planktonic foraminifera are reduced to a few disaster-tolerant survivors at the boundary, and calcareous nannoplankton nearly as severely. From that bottleneck both groups re-radiate rapidly through the Danian, producing the lineages that dominate the oceans today. Because their tests accumulate continuously on the seafloor and evolve fast, the recovery is one of the most finely resolved evolutionary radiations in the entire fossil record — and it is the reason deep-sea drilling cores can be dated to within tens of thousands of years.

Just before

Just after