Amazing stuff, but speculative to some extent!
Did the Homo sapiens spend more time in caves than Neanderthals to avoid the intense solar radiation?
"Every once in a while, Earth’s magnetic field decides to pull a switcheroo, causing the North and South poles to swap places. This phenomenon, which is known as geomagnetic reversal, has occurred about 180 times in our planet’s history.
But when the poles started to wander from their positions approximately 41,000 years ago, they never finished the job, resulting in a short-lived excursion rather than a total flip. According to the results of a new study, the event may have helped drive Neanderthals to extinction ...
When researchers created a 3D reconstruction of what Earth’s geospace system looked like during this ancient excursion, they discovered that the planet’s magnetic field shrank to about 10% of its modern strength. This weakening exposed Earth to huge amounts of solar radiation and allowed aurorae, typically only visible near the North and South poles, to be seen all over Europe and into northern Africa.
Around the same time, Homo sapiens and Neanderthal populations were coexisting in Europe, although the latter soon began to decline. ... anatomically modern humans may have protected themselves from harmful radiation by wearing more tailored clothing and increasing their use of ochre—a mineral that has sunscreen-like properties when applied to the skin. ..."
From the abstract:
"In the recent geological past, Earth’s magnetic field reduced to ~10% of the modern values and the magnetic poles shifted away from the geographic poles, causing the Laschamps geomagnetic excursion, about 41 millennia ago. The excursion lasted ~2000 years, with dipole strength reduction and tilting spanning 300 years.
During this period, the geomagnetic field’s multipolarity resembled outer planets, causing rapid magnetospheric changes.
To our knowledge, this study presents the first space plasma analysis of the excursion, linking the geomagnetic field, magnetospheric system, and upper atmosphere in sequence using feedback channels for distinct temporal epochs.
A three-dimensional reconstruction of Earth’s geospace system shows that these shifts affected auroral regions and open magnetic field lines, causing them to expand and wander toward lower latitudes.
These changes likely altered the upper atmosphere’s composition and influenced anthropological progress during that era. Looking through a modern lens, such an event would disrupt contemporary technology, including communications and satellite infrastructure."
Wandering of the auroral oval 41,000 years ago (open access)
Fig. 1. Variations in Earth’s internal magnetic field during the Laschamps Event.
Fig. 2. Reconstructed magnetospheric configurations across successive temporal epochs during the Laschamps excursion.
Fig. 3. Visualization of auroral charged particle energy flux variations and corresponding auroral zone wandering during the Laschamps excursion.
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