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The Cenozoic is the geological era from 66.00 million years ago to the present. It comprises the Palaeogene, Neogene and Quaternary. Its subdivisions organize geological and climate records; their boundaries are defined stratigraphically, with numerical ages calibrated separately.^[ref]

The Holocene is the present Quaternary epoch, following the Pleistocene, with its beginning near $0.0117$ million years ago.^[ref] Its relatively short duration makes dating conventions important when comparing high-resolution paleoclimate records. A shared epoch label does not imply uniform climate throughout its duration or across different regions.

The Neogene is the geological period from 23.04 to 2.58 million years ago in the consulted chart. It contains the Miocene and Pliocene, between the Palaeogene and Quaternary.^[ref]

Four documented examples, each tied to its actual context, are:

These examples demonstrate event- and group-dependent selectivity. They do not define one universal vulnerability ranking: the bivalve study, for instance, did not find body-size selectivity at the same end-Cretaceous genus-level event.

The Pleistocene is the Quaternary epoch preceding the Holocene, approximately $2.58$ to $0.0117$ million years ago.^[ref] Marine oxygen isotope ratios provide evidence of changing ice volume and deep-water temperature across this interval; combining many sediment-core records reduces local noise but still requires an age model.^[ref]

The Quaternary is the current geological period, beginning 2.58 million years ago. It contains the Pleistocene and Holocene epochs. Repeated major glacial cycles make its marine and continental records important for studying climate variability.^[ref]