41,000 years ago, the magnetic North Pole drifted over Europe, an event that may have influenced human evolution. A recent study explores how this episode could have differently affected Homo sapiens and Neanderthals.
During this period, Earth's magnetic field weakened, exposing the planet to increased cosmic radiation. Researchers suggest that Homo sapiens may have adapted through innovations like tailored clothing and the use of ochre as sun protection.
Neanderthals, on the other hand, appear not to have developed these technologies. This difference could explain their disappearance around 40,000 BCE, while Homo sapiens were spreading across Europe and Asia.
The study, published in
Science Advances, is based on 3D modeling of Earth's magnetic field during the Laschamps excursion. This reconstruction shows how charged particles penetrated the atmosphere, increasing UV exposure.
Homo sapiens may have sought refuge in caves for protection. Ochre, used as pigment, would have also served as natural sunscreen. These strategies might have provided a decisive advantage against hostile environmental conditions.
Researchers emphasize that these results are correlational and require further investigation. However, they open new perspectives on the impact of Earth's magnetic variations on human evolution.
This study also highlights the resilience of Homo sapiens in the face of climate and environmental changes. Their ability to innovate and adapt likely played a key role in their survival and expansion.
Finally, researchers discuss implications for the search for extraterrestrial life. A weakened magnetic field doesn't necessarily mean absence of life, as shown by the example of prehistoric Earth.
How does Earth's magnetic field protect us?
Earth's magnetic field acts as an invisible shield against charged particles from the sun and space. These particles, if they reached the surface, could damage DNA and disrupt ecosystems.
This field is generated by movements in Earth's outer core, composed of molten iron and nickel. These movements create electrical currents that, in turn, produce the magnetic field.
When this field weakens or its poles reverse, the protection it offers decreases. This can lead to increased auroras but also greater exposure to cosmic radiation.
Understanding these mechanisms is essential to anticipate the effects of future magnetic variations on our technology and health.
Why did Neanderthals disappear?
The disappearance of Neanderthals remains one of the great mysteries of human evolution. Several theories exist, ranging from climate change to competition with Homo sapiens.
Neanderthals were well adapted to Europe's cold climates, but their lack of technological innovation may have disadvantaged them. The absence of tailored clothing and effective sun protection is one example.
Homo sapiens, with their ability to innovate and adapt, could colonize new environments more easily. This behavioral flexibility may have been decisive for their survival.
Research continues to better understand interactions between these two species and the factors that led to Neanderthals' disappearance.