NASA
The Laschamps excursion, which occurred 41,000 years ago, almost led to the collapse of the earthly atmosphere. Its effect was noted in the behaviors of our ancestors, who started to spend more time in the caves and wear clothes with more coverage to protect themselves from burns.
The first meeting between Raven Garvey, Agnit Mukhopadhyay and Sanja Panovska was a bit embarrassing. One is an archaeologist and studies the way the peoples of the past interacted with their environments. The other two are geophysicals that investigate interactions between solar activity and the earthly magnetic field.
When they met, they wondered if their unconventional project, which connected space climate and human behaviorit could really overcome such a vast disciplinary pit. Now, two years later, the results – personal, professional and scientific – worth the initial discomfort.
The collaboration, which culminated in a recent journal Science Advances, began with a single question: what happened to life on Earth when the magnetic field of the planet almost collapsed about 41 thousand years ago?
Strangeness when the magnetic shield of the earth fails
This almost collapse is known as the LASCHAMPS TOURa brief but extreme geomagnetic event, which was named after the volcanic fields in France, where it was first identified. At the time of the Laschamps excursion, near the end of the Plistocene, the earth’s magnetic poles have not reversed as every few hundred thousand years. Instead, moved erratically and quicklyfor thousands of kilometers. At the same time, the intensity of the magnetic field descended to less than 10% of its current intensity.
Thus, instead of behaving like a stable magnetic bar – a dipole – as usually happens, the earthly magnetic field fragmented into multiple weak poles all over the planet. As a result, the protective force field to which scientists call magnetosphere has become distorted and permeable.
The magnetosphere usually deflects much of the solar wind and the detrimental ultraviolet radiation that, otherwise, would reach the earth’s surface.
Therefore, during the Laschamps excursion, when the magnetosphere broke, the models suggest a number of effects close to Earth. Although there is still work to be done to characterize precisely these effects, it is known that they included auroras-usually seen only in skies close to the poles, such as boreal aurora or southern aurora-a ecuadorand significantly higher doses than current harmful solar radiation.
The sky of 41,000 years may have been spectacular and threatening. When they realized this, the two geophysics wanted to know if they could have affected the people who lived at the time.
The archaeologist’s answer was: absolutely.
Human responses to ancient space climate
For people on Earth at that time, dawn may have been the most immediate and impressive effect, perhaps inspiring admiration, fear, ritual behavior or something completely different. But the archaeological record It is notoriously limited in your ability to capture this kind of cognitive or emotional responses.
Researchers are on firm ground when it comes to the physiological impacts of increased UV radiation. With the magnetic field weakened, more harmful radiation would have reached the earth’s surface, raising the Risk of sunburneye injuries, congenital defects and other health problems.
In response, people may have adopted practical measures: spend more time in caves, produce clothes made for better coverage or apply sunscreen with ocher mineral pigment to the skin. The frequency of these behaviors seems to have increased in parts of Europewhere the effects of the Laschamps excursion were pronounced and prolonged.
At this time, both Neanderthals and members of our species, Homo sapiens, lived in Europe, although their geographical distributions probably only in certain regions. Archaeological registration suggests that different populations have exhibited different approaches to environmental challenges, with some groups perhaps more dependent on shelter or material culture for protection.
It is important to emphasize that it is not suggested that the spatial climate in itself caused the increase of these behaviors or, certainly, that the Laschamps caused the neanderthals to extinction, which is a wrong interpretation of the investigation. But it can have a contributing factor – An invisible but powerful force that influenced innovation and adaptability.
Interdisciplinary collaboration
Collaborating in the midst of such a large disciplinary gap was at first intimidating. But it turned out to be deeply rewarding.
Archaeologists are used to rebuilding now invisible phenomena, such as the weather. But even archaeologists who have spent years studying the effects of climate on past behaviors and technologies may not have considered the effects of the geomagnetic field and space climate. These Effects are also invisiblepowerful and better understood through indirect evidence and modeling. Archaeologists can treat spatial climate as a vital component of the environmental history of the earth and the prediction of the future.
Similarly, geophysics, which usually work with large data sets, models and simulations, may not always be involved with some of the challenges of the space climate. Archeology adds a human dimension to science. She reminds us that the effects of spatial climate are not limited to the ionosphere. They can propagate to lived experiences by people on land, influencing the way they adapt, create and survive.
The Laschamps excursion was neither a chance nor an isolated event. Similar interruptions in the terrestrial magnetic field have happened before and will happen again. Understanding how old humans have reacted can give clues about how future events can affect our world-and perhaps even help us prepare.
