Amazing stuff, though some of it appears to be a little speculative!
Supposedly, Neanderthals were to dumb to use sunscreens and became extinct, if you believe it.
"... This phenomenon is called a geomagnetic excursion, they have occurred over 180 times in the Earth’s history. The latest occurrence of this event, happening around 41,000 years ago, is known as the Laschamps excursion. A perfectly preserved ancient tree fossil recently offered researchers a unique glimpse into the geomagnetic turmoil caused by these catastrophic events.
During the Laschamps excursion, the North Pole meandered over Europe. Using a 3D reconstruction of Earth’s geospace system, researchers found that the Earth’s magnetic field weakened to about 10% of its normal strength. While the dazzling auroras might’ve amazed our ancestors, the weak magnetic field intensified ultraviolet and cosmic radiation. ...
Archaeological evidence from the dating sites reveals a boom in the use of caves and tailored clothing, indicated by bone needles and awls. These clothes would have not only trapped warmth but also blocked harmful rays, allowing Homo sapiens to forage farther from their shelters. ...
More interestingly, the use of red and yellow ochre pigments turned up more frequently. Ochre, composed of iron oxide, clay, and silica, is more than just cave-art paint. When ground and applied to the skin, it functions effectively like a mineral-rich sunscreen. ..."
"Ancient Homo sapiens may have benefited from sunscreen, tailored clothes and the use of caves during the shifting of the magnetic North Pole over Europe about 41,000 years ago, new University of Michigan research shows. ...
Around the same time, Homo sapiens appear to have started making tailored clothing and using ochre, a mineral that has sun-protective properties when applied to the skin, with greater frequency. These behaviors could have contributed to their spread throughout Europe and Asia at a time when the Neanderthal population was declining. ...
Neanderthals and Homo sapiens coexisted in Europe, with Homo sapiens—often called anatomically modern humans—arriving roughly 56,000 years ago, says Raven Garvey, U-M associate professor of anthropology. By about 40,000 years ago, Neanderthals were no longer identified as a species in Europe. ...
“What some of the differences are between these species, between Neanderthals and anatomically modern humans, that might account for that disappearance has been a major anthropological question for decades,” ...
Clothing may have been a contributing factor ... The technological means of producing clothing that fitted to the body has been discovered at archaeological sites associated with anatomically modern humans, but not necessarily Neanderthals.
However, at sites associated with anatomically modern humans, archaeologists have found not only scrapers used in hide production, but also needles and awls—items associated with sewing. ... tailored clothing has a twofold benefit: It was significantly warmer and the added warmth meant that people could travel farther from their hearths and shelters in search of food.
Tailored clothing could have also provided another unintended benefit—protection from sun damage ..."
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."
Sunscreen, clothes and caves may have helped Homo sapiens survive 41,000 years ago (original news release)
Wandering of the auroral oval 41,000 years ago (open access)
Fig. 1. Variations in Earth’s internal magnetic field during the Laschamps Event.
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