Do Periodicities in Extinction -- with Possible Astronomical Connections -- Survive a Revision of the Geological Timescale?

TL;DR

This study re-analyzes marine extinction data with updated geological timescales, confirming a 27-million-year periodicity and challenging the Nemesis hypothesis as an explanation, while critiquing recent related studies.

Contribution

It demonstrates that the 27 Myr extinction periodicity persists with revised data, strengthening previous findings and addressing critiques of earlier analyses.

Findings

Spectral power at 27 Myr increased with new timescale

Periodicity persists at narrow bandwidth

Nemesis hypothesis remains unsupported

Abstract

A major revision of the geological timescale was published in 2012. We re-examine our past finding of a 27 Myr periodicity in marine extinction rates by re-assigning dates to the extinction data used previously. We find that the spectral power at this period is somewhat increased, and persists at a narrow bandwidth, which supports our previous contention that the Nemesis hypothesis is untenable as an explanation for the periodicity that was first noted by Raup and Sepkoski in the 1980s. We enumerate a number of problems in a recent study comparing extinction rates with time series models.