6,000 years old.

like radiometric dating, is hooey becuz Jay-eezus.

Africa went through some serious climatic weather changes in the last 6 million years. This caused enormous desserts, redistribution of animal populations, and probably the extinction of numerous lineages of the genus Homo.

Beyond that, I am sure that competition for resources and tribal warfare took out much of the rest. Other species of Homo, such as Neanderthals and Denisovans, may have simply been dissolved into the Homo sapien species, since modern day Homo sapien DNA includes both.

Denisovan intermating with sapiens would have produced a stronger hybrid, more capable of survival, so that "pure" hominins died out as the combo version expanded and absorbed them.

Smithsonian had an article some time ago about how we inherited genes from Neanderthal and Denisovan that made us more capable of fighting viruses that those two hominins had been exposed to prior to Sapiens' arrival to regions outside of Africa. The down side is that it also left us vulnerable to overactive immune responses like allergies, especially to grass and tree pollens.

As someone with multiple allergies (pollens, foods, medicines), who went into anaphylaxis in the doc's office when tested for pollens, I suspect that I have a lot of Neanderthal ancestors.

alleriges.

to the article, but I'm posting from my phone so copy and paste is a problem. If the URL isn't too long, I'll type it in.

I am at the high end of Neanderthal.

about the effects of Neanderthal and Denisovan DNA in modern humans and how their DNA affects us today. They all include references to the immune system and allergies, but you have to scroll through them to find the allergies reference. DNA from those two human relatives also affects things like blood clotting and strokes, fat metabolism, autoimmune disorders, a specific type of precancerous skin lesions (actinic keratosis), in addition to allergies.

Once beneficial according to life styles in the past, those genes are less so in the modern world environment. Besides having multiple allergies, I have also had an actinic keratosis skin lesion removed from my arm.

The articles that I found have pretty long URLs. You can find any of the articles easily by doing a search with the words "Neanderthals and allergies." Sources include Science Magazine, NPR, and Smithsonian Magazine among many others.

Fascinating.

could (likely would) be 200,000 years later than previously estimated.

FACT!!!!