Neanderthal Blood Protein Incompatibilities May Have Contributed to Extinction
Research indicates that genetic differences in Neanderthal blood proteins may have played a role in their extinction. Scientists discovered that Neanderthals had a rare RhD blood type, which was incompatible with the blood types of Denisovans and Homo sapiens. This incompatibility could have led to hemolytic disease in mixed-species offspring, resulting in severe health problems that hindered their ability to survive and reproduce. Combined with environmental challenges and competition with modern humans, these genetic factors may have contributed to the gradual decline of Neanderthal populations.
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Evidence has emerged suggesting that unique blood proteins in Neanderthals may have contributed to their eventual disappearance as a species. Research involving the genetic sequencing of early hominid populations, including Neanderthals, Denisovans, and Homo sapiens, has revealed significant differences in red blood cell antigens. These variations, according to scientists, might have played a role in their susceptibility to health issues, which could have influenced their inability to thrive in the face of changing environments and interactions with other hominid groups.
Findings from the Study
According to the study published in Scientific Reports, researchers from Aix Marseille Univ, CNRS, EFS, and ADES analysed the genetic structures responsible for red blood cell antigens in three distinct hominid groups. The focus was placed on antigens that determine blood types, including the Rh antigens responsible for positive and negative blood typing. Neanderthals were found to possess an Rh variant, identified as RhD, which remains rare in modern humans and was shown to be incompatible with the blood types of both Denisovans and Homo sapiens.
Impact of Genetic Incompatibilities
As reported by phys.org, this incompatibility, researchers explained, could have caused hemolytic disease in the offspring of Neanderthal females and males from other hominid species. Hemolytic disease in newborns, often leading to severe health complications, would have likely reduced the chances of survival and reproduction for mixed-species offspring. If interbreeding between Neanderthals and other populations became widespread, these reproductive challenges might have significantly reduced Neanderthal populations over time.
Insights into Neanderthal Decline
The researchers have suggested that while this genetic incompatibility might not be the sole cause of Neanderthal extinction, it represents a plausible contributing factor. Other pressures, such as environmental changes and competition with Homo sapiens, have been widely studied, and this research adds a new dimension to understanding the complexities of Neanderthal decline.