Comment on "A global environmental crisis 42,000 years ago".

Andrea Picin,Stefano Benazzi,Ruth Blasco,Sahra Talamo,Jean-Jacques Hublin,Chris Stringer,Jordi Rosell,Mateja Hajdinjak,Kristofer M Helgen,Pontus Skoglund

doi:10.1126/science.abi8330

Abstract

Cooper et al. (Research Articles, 19 February 2021, p. 811) propose that the Laschamps geomagnetic inversion ~42 ka BP drove global climatic shifts, causing major behavioural changes within prehistoric groups, and events of human and megafaunal extinction. Other scientific studies indicate that this proposition is unproven from the current archaeological, paleoanthropological, and genetic records.

Highlights

In our view, the Greenland ice cores and marine records do not document any notable effects of the Laschamps excursion on the global climate [4]
In Iberia, Neanderthals may have persisted after a threshold of ~40 ka BP [(10) and references therein], whereas the chronology of the last Neanderthals in central and western Asia is still virtually unknown
If the weakened geomagnetic field allowed a rise in ultraviolet radiation in equatorial and low latitudes, H. sapiens in Africa should have been even more affected than groups living in temperate environments

Summary

Introduction

The Greenland ice cores and marine records do not document any notable effects of the Laschamps excursion on the global climate [4]. Cooper et al argue that Laschamps-associated changes in climate can be linked to megafaunal extinctions, especially in Australia, which they suggest peaked at 42.1 ka.

Results

Conclusion