Editing Openai/69177fbb-14c4-800f-bc57-ccb5a1d88c95 (section)

==== When Neanderthal DNA entered the Homo sapiens gene pool, natural selection removed most of the segments that touched: ====
* neural progenitor proliferation
* cortical development pathways
* synaptic gene networks
* language-related loci (e.g., FOXP2-adjacent regions)
* brain size and skull growth patterns

This wasn’t mild drift—it was strong negative selection, especially in high-expression brain regions. Large comparative studies show a massive underrepresentation of Neanderthal segments in exactly the regions that would need to survive if they contributed to autistic traits.

If Neanderthals carried alleles shaping “autistic-like cognition,” and those alleles were advantageous or even neutral in Homo sapiens, selection would have kept them. Instead, the opposite happened.

This is the hardest single blow to RDOS’s framework.