Neanderthal Y chromosomes and mitochondrial DNA

https://www.science.org/content/article/how-neanderthals-lost-their-y-chromosome
Last year we had a paper that looked at Neanderthal genomes and determined that around 250,000 years ago a group of African Homo sapiens left Africa and interbred with Neanderthal.  The African population died out or was absorbed by the Neanderthal population, and we got back some of that 250,000 year old African DNA by interbreeding with Neanderthal around 60,000 years ago when Modern humans made a successful foray out of Africa and took over the territory of the Neanderthals and Denisovans.
It looks like that around 250,000 years ago the Africans that interbred with Neanderthals transferred their Y chromosomes and mitochondrial genomes to Neanderthals.  Both the paternal Y chromosome and maternal mitochondria took over the Neanderthal population before modern humans interbred with them 60,000 years ago.  Even though the 250,000 year old African DNA is only a small fraction of the Neanderthal genomes there must have been selection for the African Y chromosome and mitochondrial genome.
Ron Okimoto