Astrophysical Hypothesis on Neanderthal Extinction Examined

Neanderthals, a closely related species to modern humans, have been a focal point of scientific inquiry, particularly concerning their extinction approximately 40,000 years ago. A recent study from the University of Michigan, published in the journal *Science Advances*, proposes a novel astrophysical explanation for this extinction, suggesting that a geomagnetic event known as the Laschamp excursion may have played a critical role. Led by Agnit Mukhopadhyay, a researcher specializing in space physics, the study posits that a significant weakening of the Earth's magnetic field during this period allowed increased cosmic and ultraviolet radiation to penetrate the atmosphere, creating harsh environmental conditions that Neanderthals could not endure.

The Laschamp event, which occurred around 41,000 years ago, is characterized by a shift in the Earth's magnetic poles. Mukhopadhyay's research indicates that the resultant exposure to elevated levels of radiation could have provided modern humans, or Homo sapiens, with a survival advantage due to their presumed use of protective clothing and shelters. This advantage is underscored by evidence that suggests early Homo sapiens employed ochre, a mineral with potential UV-blocking properties, and utilized caves for habitation, which may have offered additional protection against the elements.

However, the hypothesis raises significant questions regarding its scope and underlying assumptions. Critics, including José-Miguel Tejero, a senior researcher specializing in Prehistory at the Universitat de Barcelona, argue that the archaeological record does not support a direct correlation between the Laschamp event and a demographic collapse of Neanderthal populations. Tejero highlights that there is no substantial evidence of widespread mortality among Neanderthals that coincided with the geomagnetic event.

The concept that Neanderthals lacked the technological advancements necessary for survival, such as sewing needles for tight-fitting clothing, is another contentious point. While it is true that the earliest known needles in Eurasia are associated with Homo sapiens, archaeological evidence indicates that Neanderthals processed animal hides, suggesting they employed alternative methods for creating garments. Thus, the assertion that they were wholly unprotected from environmental hazards may be an oversimplification of their adaptive capabilities.

Furthermore, the use of ochre is documented in Neanderthal contexts for over 100,000 years, indicating that this practice was not unique to modern humans. The multifaceted applications of ochre, which may have included symbolic and therapeutic uses, complicate the claim that it served solely as a protective measure against solar radiation.

Population dynamics also played a crucial role in the fate of Neanderthals. The significantly smaller population sizes of Neanderthals compared to the burgeoning Homo sapiens might have contributed to their assimilation into the latter's gene pool rather than outright extinction. Genetic studies have demonstrated that contemporary humans carry Neanderthal DNA, suggesting a complex interspecies interaction rather than a complete eradication of Neanderthals.

In conclusion, while Mukhopadhyay's astrophysical hypothesis provides an intriguing perspective on Neanderthal extinction, it is essential to approach such claims with a critical lens, integrating a comprehensive array of archaeological, paleoanthropological, and genetic evidence. The extinction of Neanderthals is likely a multifactorial phenomenon influenced by environmental changes, technological advancements, and demographic pressures, underscoring the need for ongoing research in this captivating area of human history.