Why did Initial mtDNA Studies not find any evidence of interbreeding between Neanderthals and modern humans?
The early mtDNA studies ruled out the possibility of interbreeding between contemporary humans and the Neanderthals. However, recent genetic studies indicate that the archaic human forms did interbreed with modern humans and contributed to their genetic makeup. This variance in results can be attributed to the fact that earlier studies focused on a single part of the genome, in this case, the mitochondria. However, subsequent studies diversified into other regions of the genome and found intriguing signs of interbreeding between the modern and archaic humans. The earlier studies, therefore, failed to get the evidence because they failed to diversify their research into other regions of the genome.
Delegate your assignment to our experts and they will do the rest.
How is the Hybridization model different from the Replacement model and Assimilation model?
The Hybridization model differs with the replacement model and assimilation models in explaining the interconnection between the archaic human forms and modern humans. The model suggests that interbreeding between the ancient human forms and modern humans occurred in isolated instances. This means that some of the modern humans bear genetic makeup of the archaic species while others do not. The assimilation model, however, suggests that interbreeding was common and was widespread; hence the majority of the modern humans are genetically linked to the ancient species. The replacement model disputes the possibility of interbreeding between the archaic human-like species and modern humans. The model supposes that the modern human species individually emerged and replaced the other human-like forms.
In what way were Neanderthal DNA contributions evolutionally advantageous to modern humans?
The Neanderthal DNA had several benefits to modern humans. The DNA contributions enabled modern humans to adapt to the primitive environment. This ensured their survival in an environment that was rather hostile for their existence. For instance, the EPAS1 gene enhanced the body response to low oxygen levels hence enabling survival in low altitude areas. Also, other inherited genes found in the Neanderthal DNA enabled modern humans to be more resistant to diseases. These traits ensured the survival of modern humans through the archaic environment into the modern environment.
